Tuning the Stability and Kinetics of Dioxazaborocanes Barthelmes, K.; Yaginuma, K.; Matsumoto, A. Chem. Eur. J.2025, 31(5), e202402625. Abstract/Cover
We investigated the equilibrium reaction of boronic acid (BA), diethanolamines (DEA), and 1,3,6,2-dioxazaborocanes (DOAB) in aqueous solutions, both theoretically and experimentally. Our findings show that the association constant can be adjusted by substituting BA and DEA derivatives, ranging from 100 to 103 M−1, exhibiting a bell-shaped pH dependency. The highest stability was achieved when the pKa values of DEA and BA were closely matched. This approach enabled the preparation of a highly stable DOAB under physiological conditions. Furthermore, the hydrolysis kinetics of DOABs were controllable over a range of five orders of magnitude based on the substituent’s steric effect. In the slowest case, this resulted in quasi-static stability with only 1 % cleavage in the first hour, followed by a week-long cleavage period to reach equilibrium. These insights could establish a unique chemistry platform for designing scheduled cleavability on a day-to-week timescale, relevant to protein engineering, immunotherapy, and other smart drug delivery applications.
2024
Increased mechanical stability and permeability by filling the
interconnected pores of porous microneedles Barthelmes, K.; Sathitaphiwan, K.; Janwimaluang, N.; Ikehara, K.; Matsumoto, A. Jpn. J. Appl. Phys.2024, 63(2). Abstract
A new polymeric microneedle (MN) fabrication technique is described in
order to facilitate both higher mechanical stability and continuous drug
release capability, a well-recognized challenge in the community. The
technique involves filling the pores of a porous MN (PMN) array with a
hydrogel. Cellulose acetate (CA) was used to prepare PMN, the
interconnected cavity of which was then occupied by a crosslinked
poly(N-isopropylacrylamide) hydrogel. Alkali treatment of the PMN array
resulted in deacetylation of CA and improved the hydrophilicity on the
surface. The hydrogel was readily incorporated by thermal polymerization
of the monomers soaked to the PMN array. Mechanical strength tests
demonstrated that pore filling enhanced the PMN stability by up to 50%,
which was well-above the threshold required for skin penetration. The
permeability of the hydrogel remained after pore filling and the drug
release rate could be varied by alkali treatment process.
Poly(ethylene Glycol) (PEG)–OligoRNA Hybridization to mRNA Enables Fine-Tuned Polyplex PEGylation for Spleen-Targeted mRNA Delivery Suzuki, M.; Mochida, Y.; Hori, M.; Hayashi, A.; Toh, K.; Tockary, T. A.; Liu, X.; Marx, V.; Yokoo, H.; Miyata, K.; Oba, M.; Uchida, S. Small Science2024, 4(4), 2300258. Abstract
Organ-selective targeting of mRNA polyplexes has been rarely explored despite the substantial potential of polymer-based systems in mRNA delivery. In this study, spleen-selective delivery of polyplexes is achieved by employing mRNA engineering to coat them with poly(ethylene glycol) (PEG). In this approach, mRNA is hybridized with PEGylated complementary RNA oligonucleotides (PEG–OligoRNAs), followed by the addition of linear poly(ethyleneimine). In this method, it is ensured that nearly all added PEG strands bind to the polyplexes, thereby enabling precise control of PEG amounts on the surface. Following systemic injection into mice, non-PEGylated polyplexes yield robust protein expression in the lung and spleen. Intriguingly, adding a small number of PEG–OligoRNAs drastically reduces protein expression efficiency in the lung while preserving it in the spleen, realizing spleen targeting of mRNA polyplexes. Furthermore, PEGylated polyplexes demonstrate their potential utility in mRNA vaccination. In mechanistic analyses, non-PEGylated polyplexes immediately agglomerate in the blood and deposit in the lung. Coating polyplexes with a small amount of short PEG effectively prevents these processes. Notably, even slight changes in PEG amounts and lengths dramatically impact the physicochemical properties and biological functionalities of the polyplexes, emphasizing the benefits of an mRNA engineering-based approach for fine-tuning polyplex PEG coating.
Designed modular protein hydrogels for biofabrication Dranseike, D.; Ota, Y.; Edwardson, T. G. W.; Guzzi, E. A.; Hori, M.; Nakic, Z. R.; Deshmukh, D. V.; Levasseur, M. D.; Mattli, K.; Tringides, C. M.; Zhou, J.; Hilvert, D.; Peters, C.; Tibbitt, M. W. Acta Biomater.2024, 177, 107-117. Abstract
Designing proteins that fold and assemble over different length scales provides a way to tailor the mechanical properties and biological performance of hydrogels. In this study, we designed modular proteins that self-assemble into fibrillar networks and, as a result, form hydrogel materials with novel properties. We incorporated distinct functionalities by connecting separate self-assembling (A block) and cell-binding (B block) domains into single macromolecules. The number of self-assembling domains affects the rigidity of the fibers and the final storage modulus G′ of the materials. The mechanical properties of the hydrogels could be tuned over a broad range (G′ = 0.1 – 10 kPa), making them suitable for the cultivation and differentiation of multiple cell types, including cortical neurons and human mesenchymal stem cells. Moreover, we confirmed the bioavailability of cell attachment domains in the hydrogels that can be further tailored for specific cell types or other biological applications. Finally, we demonstrate the versatility of the designed proteins for application in biofabrication as 3D scaffolds that support cell growth and guide their function.
Functionalization of Poly-L-Lactic Acid Microneedle Tips using Hydrogel Photopolymerization Fukuhara, M.; Takehara, H.; Kanda, Y.; Matsumoto, A.; Ichiki, T. J. Photopolym. Sci. Tec.2024, 37(2), 233-237. Abstract
Although the diagnostic utility of interstitial fluid (ISF) has been extensively explored, collecting and sensing ISF in the body remains challenging. Microneedle devices offer a promising approach for minimally invasive methods to obtain ISF with a small volume or to sense biomolecules in the ISF within the body. In this study, we developed a microneedle with a small volume hydrogel block at the needle tip. The hydrogel block was formed through a photopolymerization reaction of polyethylene glycol diacrylate (PEGDA) under 365 nm irradiation. The hydrogel block measured 100 µm in diameter and 100 µm in length, with a total volume of 0.79 nL. The fabricated microneedle had a high-aspect ratio shape (500 µm in base diameter, 200 µm in top diameter, and 2000 µm in length), reaching the reticular layer containing blood vessels. Therefore, microneedle devices can be utilized to obtain ISF with a small volume and to sense biomolecules within the body.
Size-Dependent Glioblastoma Targeting by Polymeric Nanoruler with Prolonged Blood Circulation Ishibashi, Y.; Naito, M.; Watanuki, Y.; Hori, M.; Ogura, S.; Taniwaki, K.; Cho, M.; Komiya, R.; Mochida, Y.; Miyata, K. Bioconjugate Chem.2024, 35(8), 1154-1159. Abstract
Currently, there is no effective treatment for glioblastoma multiforme (GBM), the most frequent and malignant type of brain tumor. The blood–brain (tumor) barrier (BB(T)B), which is composed of tightly connected endothelial cells and pericytes (with partial vasculature collapse), hampers nanomedicine accumulation in tumor tissues. We aimed to explore the effect of nanomedicine size on passive targeting of GBM. A series of size-tunable poly(ethylene glycol) (PEG)-grafted copolymers (gPEGs) were constructed with hydrodynamic diameters of 8–30 nm. Biodistribution studies using orthotopic brain tumor-bearing mice revealed that gPEG brain tumor accumulation was maximized at 10 nm with ∼14 dose %/g of tumor, which was 19 times higher than that in the normal brain region and 4.2 times higher than that of 30-nm gPEG. Notably, 10-nm gPEG exhibited substantially higher brain tumor accumulation than 11-nm linear PEG owing to the prolonged blood circulation property of gPEGs, which is derived from a densely PEG-packed structure. 10 nm gPEG exhibited deeper penetration into the brain tumor tissue than the larger gPEGs did (>10 nm). This study demonstrates, for the first time, the great potential of a nanomedicine downsizing strategy for passive GBM targeting.
Stimulus-responsive assembly of nonviral nucleocapsids Hori, M.; Steinauer, A.; Tetter, S.; Hälg, J.; Manz, E.-M.; Hilvert, D. Nat. Commun.2024, 15(1), 3576. Abstract
Controlled assembly of a protein shell around a viral genome is a key step in the life cycle of many viruses. Here we report a strategy for regulating the co-assembly of nonviral proteins and nucleic acids into highly ordered nucleocapsids in vitro. By fusing maltose binding protein to the subunits of NC-4, an engineered protein cage that encapsulates its own encoding mRNA, we successfully blocked spontaneous capsid assembly, allowing isolation of the individual monomers in soluble form. To initiate RNA-templated nucleocapsid formation, the steric block can be simply removed by selective proteolysis. Analyses by transmission and cryo-electron microscopy confirmed that the resulting assemblies are structurally identical to their RNA-containing counterparts produced in vivo. Enzymatically triggered cage formation broadens the range of RNA molecules that can be encapsulated by NC-4, provides unique opportunities to study the co-assembly of capsid and cargo, and could be useful for studying other nonviral and viral assemblies.
総説
ボロン酸高分子ネットワークバイオ材料の設計と医療応用 (Design and medical application of boronic acid polymer network biomaterials) 松元 亮. ネットワークポリマー論文集 (Network Polymer Papers) 2024, 45(1), 44-54. Abstract
Wearable Artificial Pancreas Device Technology Matsumoto, A. Wearable Biosensing in Medicine and Healthcare2024, 249-266 (Springer). Abstract
This chapter covers the development of closed-loop insulin delivery systems known as artificial pancreas systems (APSs). These systems can be either electronics-based or electronics-free, and there is a continuous drive to make them both wearable and user-friendly. First, we outline the development and validation status of electronics-based APSs. Then, we summarize the growing research effort to develop electronics-free, chemically-controlled APSs, with particular emphasis on ongoing efforts to make them wearable. We also discuss current challenges, possible solutions, and future perspectives based on promising results from a recent clinical trial.
貼るだけ人工膵臓デバイスの開発 (Development of a stick-on ’artificial pancreas’ device) 松元 亮; 松本 裕子; 金井 紗綾香; Barthelmes, K.; 堀 真緒; 田中 都; 伊藤 美智子; 菅波 孝祥. 血糖測定・コントロールの最新動向 (Latest Trends in Blood Glucose Monitoring and Control) 2024, Chapter 5.4, (CMC Publishing Co., Ltd).
Drug Delivery Systems for Muscles Naito, M.; Hori, M. Drug Delivery Systems for Musculoskeletal Tissues2024, 189-208 (Springer). Abstract
Muscle diseases and disorders can cause a loss of function and mobility, significantly reducing the quality of life for patients and their caregivers. The treatment options for muscle diseases and disorders are limited or, in most cases, unavailable. One of the barriers to the development of novel treatment modalities is the low diffusion rate of drugs from blood to muscle, known as the “blood-muscle barrier.” Therefore, drug delivery systems and strategies targeting muscles are essential for the effective treatment of muscle diseases and disorders. This chapter provides a comprehensive overview of muscle-targeted drugs and their delivery strategies to the musculoskeletal system. Fundamental information on the structure and molecular biology of muscles is also described to help further our understanding of the existing muscle-targeted drug delivery systems.
2023
Block catiomers with flanking hydrolyzable tyrosinate groups enhance in vivo mRNA delivery via π-π stacking-assisted micellar
assembly Yang, W.; Miyazaki, T.; Nakagawa, Y.; Boonstra, E.; Masuda, K.; Nakashima, Y.; Chen, P.; Mixich, L.; Barthelmes, K.; Matsumoto, A.; Mi, P.; Uchida, S.; Cabral, H. Sci. Technol. Adv. Mater.2023, 24(1). Abstract
Messenger RNA (mRNA) therapeutics have recently demonstrated high
clinical potential with the accelerated approval of SARS-CoV-2 vaccines.
To fulfill the promise of unprecedented mRNA-based treatments, the
development of safe and efficient carriers is still necessary to achieve
effective delivery of mRNA. Herein, we prepared mRNA-loaded nanocarriers
for enhanced in vivo delivery using biocompatible block copolymers
having functional amino acid moieties for tunable interaction with mRNA.
The block copolymers were based on flexible poly(ethylene
glycol)-poly(glycerol) (PEG-PG) modified with glycine (Gly), leucine
(Leu) or tyrosine (Tyr) via ester bonds to generate block catiomers.
Moreover, the amino acids can be gradually detached from the block
copolymers after ester bond hydrolyzation, avoiding cytotoxic effects.
When mixed with mRNA, the block catiomers formed narrowly distributed
polymeric micelles with high stability and enhanced delivery efficiency.
Particularly, the micelles based on tyrosine-modified PEG-PG
(PEG-PGTyr), which formed a polyion complex (PIC) and pi-pi stacking
with mRNA, displayed excellent stability against polyanions and promoted
mRNA integrity in serum. PEG-PGTyr-based micelles also increased the
cellular uptake and the endosomal escape, promoting high protein
expression both in vitro and in vivo. Furthermore, the PEG-PGTyr-based
micelles significantly extended the half-life of the loaded mRNA after
intravenous injection. Our results highlight the potential of
PEG-PGTyr-based micelles as safe and effective carriers for mRNA,
expediting the rational design of polymeric materials for enhanced mRNA
delivery.
Lysosomal cholesterol overload in macrophages promotes liver fibrosis in
a mouse model of NASH Itoh, M.; Tamura, A.; Kanai, S.; Tanaka, M.; Kanamori, Y.; Shirakawa, I.; Ito, A.; Oka, Y.; Hidaka, I.; Takami, T.; Honda, Y.; Maeda, M.; Saito, Y.; Murata, Y.; Matozaki, T.; Nakajima, A.; Kataoka, Y.; Ogi, T.; Ogawa, Y.; Suganami, T. J. Exp. Med.2023, 220(11). Abstract
Lysosomal cholesterol overload triggers phenotypic changes and
profibrotic activation of macrophages around dead hepatocytes containing
cholesterol crystals in the development of NASH. Cholesterol excretion
from macrophages using & beta;-cyclodextrin polyrotaxane, which is
designed to release & beta;-cyclodextrin in lysosomes, alleviates liver
fibrosis.
Accumulation of lipotoxic lipids, such as free cholesterol, induces
hepatocyte death and subsequent inflammation and fibrosis in the
pathogenesis of nonalcoholic steatohepatitis (NASH). However, the
underlying mechanisms remain unclear. We have previously reported that
hepatocyte death locally induces phenotypic changes in the macrophages
surrounding the corpse and remnant lipids, thereby promoting liver
fibrosis in a murine model of NASH. Here, we demonstrated that lysosomal
cholesterol overload triggers lysosomal dysfunction and profibrotic
activation of macrophages during the development of NASH. &
beta;-cyclodextrin polyrotaxane (& beta;CD-PRX), a unique
supramolecule, is designed to elicit free cholesterol from lysosomes.
Treatment with & beta;CD-PRX ameliorated cholesterol accumulation and
profibrotic activation of macrophages surrounding dead hepatocytes with
cholesterol crystals, thereby suppressing liver fibrosis in a NASH
model, without affecting the hepatic cholesterol levels. In vitro
experiments revealed that cholesterol-induced lysosomal stress triggered
profibrotic activation in macrophages predisposed to the steatotic
microenvironment. This study provides evidence that dysregulated
cholesterol metabolism in macrophages would be a novel mechanism of
NASH.
Loss of KDM6B epigenetically confers resistance to lipotoxicity in nonalcoholic fatty liver disease-related HCC Hatano, M.; Akiyama, Y.; Shimada, S.; Yagi, K.; Akahoshi, K.; Itoh, M.; Tanabe, M.; Ogawa, Y.; Tanaka, S. Hepatol. Commun.2023, 7(10), e0277. Abstract
Background: NAFLD caused by abnormalities in hepatic lipid metabolism is
associated with an increased risk of developing HCC. The molecular
mechanisms underlying the progression of NAFLD-related HCC are not fully
understood. We investigated the molecular mechanism and role of KDM6B
downregulation in NAFLD-related HCC after the KDM6B gene was identified
using microarray analysis as commonly downregulated in mouse
NAFLD-related HCC and human nonhepatitis B and nonhepatitis C
viral-HCC.Methods: The 5-hydroxymethylcytosine levels of KDM6B in HCC
cells were determined using glycosylated hydroxymethyl-sensitive PCR.
Microarray and chromatin immunoprecipitation analyses using
KDM6B-knockout (KO) cells were used to identify KDM6B target genes.
Lipotoxicity was assessed using a palmitate-treated cell proliferation
assay. Immunohistochemistry was used to evaluate KDM6B expression in
human HCC tissues.Results: KDM6B expression levels in HCC cells
correlated with the 5-hydroxymethylcytosine levels in the KDM6B gene
body region. Gene set enrichment analysis revealed that the lipid
metabolism pathway was suppressed in KDM6B-KO cells. KDM6B-KO cells
acquired resistance to lipotoxicity (p < 0.01) and downregulated the
expression of G0S2, an adipose triglyceride lipase/patatin like
phospholipase domain containing 2 (ATGL/PNPLA2) inhibitor, through
increased histone H3 lysine-27 trimethylation levels. G0S2 knockdown in
KDM6B-expressed HCC cells conferred lipotoxicity resistance, whereas
ATGL/PNPLA2 inhibition in the KDM6B-KO cells reduced these effects.
Immunohistochemistry revealed that KDM6B expression was decreased in
human NAFLD-related HCC tissues (p < 0.001), which was significantly
associated with decreased G0S2 expression (p = 0.032).Conclusions:
KDM6B-disrupted HCC acquires resistance to lipotoxicity via ATGL/PNPLA2
activation caused by epigenetic downregulation of G0S2 expression.
Reduced KDM6B and G0S2 expression levels are common in NAFLD-related
HCC. Targeting the KDM6B-G0S2-ATGL/PNPLA2 pathway may be a useful
therapeutic strategy for NAFLD-related HCC.
総説
"Borono-lectin"-mediated Crosstalk and Its Application to Bioengineering Matsumoto, A. Yakugaku Zasshi-J. Pharm. Soc. Jpn.2023, 143(5), 435-441. Abstract
Boronic acids are able to reversibly interact with the diol groups, a commonly found motif in biomolecules
including sugars, ribose and catechols. For their carbohydrate-binding properties, they can be regarded as a synthetic
mimic of lectins and often termed as “borono-lectins.” Importantly, the borono-lectins platform can be chemically tailored
to manifest a broad profile of binding strength and specificity. Besides the structural versatility, some derivatives
can undergo a sharp inversion in the state of hydration in synchronization with the molecular recognitions. This feature,
when combined with amphiphilic polymeric backbones, translates into many creative principles for fine-tuning or switching
the hydration and more complex molecular assemblies in a way interactive with biology. Here we provide a brief overview of
our recent efforts on the related applications with special focuses on smart insulin delivery systems and sialic acid detections
relevant to cancer diagnosis and treatment among others.
’ボロノレクチン’を応用した糖鎖シアル酸検出と腫瘍ターゲティング (Sugar chain sialic acid detection and tumor targeting using ’boronorectin’) 松元 亮. バイオマテリアル (Journal of Japanese Society for Biomaterials) 2023, 42(1), 92-93.
著書
もっとよくわかる!線維化と疾患 (Understand more! Fibrosis and disease) 菅波 孝祥; 田中 都; 伊藤 美智子. 実験医学別冊 もっとよくわかる!シリーズ (Experimental Medicine Special Edition: Understand more! series) 2023, (羊土社). Abstract
Transepithelial delivery of insulin conjugated with phospholipid-mimicking polymers via biomembrane fusion-mediated transcellular pathways Hatano, H.; Meng, F.; Sakata, M.; Matsumoto, A.; Ishihara, K.; Miyahara, Y.; Goda, T. Acta Biomater.2022, 140, 674-685. Abstract
Epithelial barriers that seal cell gaps by forming tight
junctions to prevent the free permeation of nutrients, electrolytes, and
drugs, are essential for maintaining homeostasis in multicellular
organisms. The development of nanocarriers that can permeate epithelial
tissues without compromising barrier function is key for establishing a
safe and efficient drug delivery system (DDS). Previously, we have
demonstrated that a water-soluble phospholipid-mimicking random
copolymer, poly(2-methacryloyloxyethyl phosphorylcholine30- random n
-butyl methacrylate70) (PMB30W), enters the cytoplasm of live cells by
passive diffusion manners, without damaging the cell membranes. The
internalization mechanism was confirmed to be amphiphilicity-induced
membrane fusion. In the present study, we demonstrated energy
independent permeation of PMB30W through the model epithelial barriers
of Madin-Darby canine kidney (MDCK) cell monolayers in vitro . The
polymer penetrated epithelial MDCK monolayers via transcellular pathways
without breaching the barrier functions. This was confirmed by our
unique assay that can monitor the leakage of the proton as the smallest
indicator across the epithelial barriers. Moreover, energy independent
transepithelial permeation was achieved when insulin was chemically
conjugated with the phospholipid-mimicking nanocarrier. The bioactivity
of insulin as a growth factor was found to be maintained even after
translocation. These fundamental findings may aid the establishment of
transepithelial DDS with advanced drug efficiency and safety.Statement
of significanceA nanocarrier that can freely permeate epithelial tissues
without compromising barrier function is key for successful DDS.
Existing strategies mainly rely on paracellular transport associated
with tight junction breakdown or transcellular transport via transporter
recognition-mediated active uptake. These approaches raise concerns
about efficiency and safety. In this study, we performed non-endocytic
permeation of phospholipid-mimicking polymers through the model
epithelial barriers in vitro . The polymer penetrated via transcytotic
pathways without breaching the barriers of biomembrane and tight
junction. Moreover, transepithelial permeation occurred when insulin was
covalently attached to the nanocarrier. The bioactivity of insulin was
maintained even after translocation. The biomimetic design of
nanocarrier may realize safe and efficient transepithelial DDS.&
nbsp;(c) 2021 Acta Materialia Inc. Published by Elsevier Ltd. All rights
reserved.
A Porous Reservoir-Backed Boronate Gel Microneedle for Efficient Skin Penetration and Sustained Glucose-Responsive Insulin Delivery Chen, S.; Miyazaki, T.; Itoh, M.; Matsumoto, H.; Moro-oka, Y.; Tanaka, M.; Miyahara, Y.; Suganami, T.; Matsumoto, A. Gels2022, 8(2), 74. Abstract
Recently, phenylboronic acid (PBA) gel containing microneedle (MN) technology with acute and sustained glucose-sensitive functionality has attracted significant research attention. Herein, we report a polyvinyl alcohol(PVA)-coated MNs patch with an interconnected porous gel drug reservoir for enhanced skin penetration efficiency and mechanical strength. The hybrid MNs patch fabricated with a novel, efficient method displayed a “cake-like” two-layer structure, with the tip part being composed of boronate-containing smart gel attached to a porous gel layer as a drug reservoir. The porous structure provides the necessary structural support for skin insertion and space for insulin loading. The mechanical strength of the hybrid MNs patch was further enhanced by surface coating with crystallized PVA. Compared with MNs patches attached to hollow drug reservoirs, this hybrid MNs patch with a porous gel reservoir was shown to be able to penetrate the skin more effectively, and is promising for on-demand, long-acting transdermal insulin delivery with increased patient compliance.
Determination of intracellular ascorbic acid using tandem mass
spectrometry Abe, C.; Higuchi, O.; Matsumoto, A.; Miyazawa, T. Analyst2022, 147(12), 2640-2643. Abstract
Ascorbic acid is involved in a variety of biological events.
Nevertheless, its detailed intracellular behavior remains unexplored due
to a lack of sensitive analytical methods. Here we report a method using
HPLC-ESI-MS/MS achieving the lowest detection limit ever reported (1
pg), to provide mechanistic insight into the intracellular ascorbic acid
physiology.
Sialic acid biosensing by post-printing modification of PEDOT:PSS with
pyridylboronic acid Fujisaki, H.; Matsumoto, A.; Miyahara, Y.; Goda, T. Sci. Technol. Adv. Mater.2022, 23(1), 525-534. Abstract
A poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)
(PEDOT:PSS)-based conducting polymer, which has biorecognition
capabilities, has promising biosensing applications. Previously, we
developed a facile method for post-printing chemical modification of
PEDOT:PSS thin films from commercial sources. Molecular recognition
elements were directly introduced into the PSS side chain by a two-step
chemical reaction: introduction of an ethylenediamine linker via an acid
chloride reaction of the sulfonate moiety, and subsequent receptor
attachment to the linker via amine coupling. In this study, the same
method was used to introduce 6-carboxypyridine-3-boronic acid
(carboxy-PyBA) into the linker for specifically detecting
N-acetylneuraminic acid (sialic acid, SA), as a cancer biomarker. The
surface-modified PEDOT:PSS films were characterized by X-ray
photoelectron spectroscopy, attenuated total reflection
Fourier-transform infrared spectroscopy, and static water contact angle
and conductivity measurements. The specific interaction between PyBA and
SA was detected by label-free reagent-free potentiometry. The
SA-specific negative potential responses of modified PEDOT:PSS
electrodes, which was ascribed to an SA carboxyl anion, were observed in
a physiologically relevant SA range (1.6-2.9 mM) at pH 5, in a
concentration-dependent manner even in the presence of 10% fetal bovine
serum. The sensitivity was -2.9 mV/mM in 1-5 mM SA with a limit of
detection of 0.7 mM. The sensing performances were almost equivalent to
those of existing graphene-based electrical SA sensors. These results
show that our chemical derivatization method for printing PEDOT:PSS thin
films will have applications in SA clinical diagnostics.
総説
Food Antioxidants and Aging: Theory, Current Evidence and Perspectives Miyazawa, T.; Abe, C.; Burdeos, G. C.; Matsumoto, A.; Toda, M. Nutraceuticals2022, 2(3), 181-204. Abstract
The concept of food and aging is of great concern to humans. So far, more than 300 theories of aging have been suggested, and approaches based on these principles have been investigated. It has been reported that antioxidants in foods might play a role in human aging. To clarify the current recognition and positioning of the relationship between these food antioxidants and aging, this review is presented in the following order: (1) aging theories, (2) food and aging, and (3) individual food antioxidants and aging. Clarifying the significance of food antioxidants in the field of aging will lead to the development of strategies to achieve healthy human aging.
2021
pH-responsive Adsorption and Dissociation of Sialic Acid Expressed
Protein on Boronic Acid Immobilized Surface Horiguchi, Y.; Barthelmes, K.; Miyahara, Y.; Matsumoto, A. Chem. Lett.2021, 50(8), 1467-1469. Abstract
Detection and isolation of sialic acid (SA) over-expressed biomolecules
is of continuous interest in cancer-related research. Boronic acid-based
SA-recognition chemistry provides a synthetic molecular basis for such
techniques. 5-Boronopicolinic acid, a derivative with the reportedly
highest SA-binding strength, was immobilized to a gold surface and
studied for its interaction with fetuin, a blood-circulating
glycoprotein implicated in cancers. A submicron-molar level sensitivity
was achievable, while the sample could be readily dissociated by
modulating the pH.
Potentiometric Determination of Circulating Glycoproteins by Boronic
Acid End-Functionalized Poly(ethylene glycol)-Modified Electrode Matsumoto, A.; Osawa, S.; Arai, T.; Maejima, Y.; Otsuka, H.; Miyahara, Y. Bioconjugate Chem.2021, 32(2), 239-244. Abstract/Cover
Despite tremendous complexity in glycan structure, sialic acid (SA)
provides an analytically accessible index for glycosylation, owing to
its uniquely anionic nature and glycan-chain terminal occupation. Taking
advantage of boronic acid (BA) based SA-recognition chemistry, we here
demonstrate a label-free, no enzymatic, potentiometric determination of
fetuin, a blood-circulating glycoprotein implicated in physiological and
various pathological states. A phenylboronic acid (PBA)
omega-end-functionalized poly(ethylene glycol) (PEG) with an
alpha-tethering unit bearing pendent alkyne groups was “grafted-to”
a gold electrode modified with 11-azide-undecathiol by a
copper-catalyzed azide-alkyne cycloaddition reaction. Using the
electrode, fetuin was potentiometrically detectable with a mu
M-order-sensitivity that is comparable to what is found in
blood-collected specimen. Our finding may have implications for
developing a remarkably economic hemodiagnostic technology with ease of
downsizing and mass production.
Phosphorylcholine-Installed Nanocarriers Target Pancreatic Cancer Cells
through the Phospholipid Transfer Protein Hong, T.; Miyazaki, T.; Matsumoto, A.; Koji, K.; Miyahara, Y.; Anraku, Y.; Cabral, H. ACS Biomater. Sci. Eng.2021, 7(9), 4439-4445. Abstract
Phosphorylcholine (PC) has been used to improve the water solubility and
biocompatibility of biomaterials. Here, we show that PC can also work as
a ligand for targeting cancer cells based on their increased
phospholipid metabolism. PC-installed multiarm poly(ethylene glycol)s
and polymeric micelles achieved high and rapid internalization in
pancreatic cancer cells. This enhanced cellular uptake was drastically
reduced when the cells were incubated with excess free PC or at 4
degrees C, as well as by inhibiting the phospholipid transfer protein
(PLTP) on the surface of cancer cells, indicating an energy dependent
active transport mediated by PLTP.
Block catiomer with flexible cationic segment enhances complexation with
siRNA and the delivery performance in vitro Yang, W.; Miyazaki, T.; Chen, P.; Hong, T.; Naito, M.; Miyahara, Y.; Matsumoto, A.; Kataoka, K.; Miyata, K.; Cabral, H. Sci. Technol. Adv. Mater.2021, 22(1), 850-863. Abstract
RNA interference (RNAi) by small interfering RNAs (siRNAs) is a
promising therapeutic approach. Because siRNA has limited intracellular
access and is rapidly cleared in vivo, the success of RNAi depends on
efficient delivery technologies. Particularly, polyion complexation
between block catiomers and siRNA is a versatile approach for
constructing effective carriers, such as unit polyion complexes (uPIC),
core-shell polyion complex (PIC) micelles and vesicular siRNAsomes, by
engineering the structure of block catiomers. In this regard, the
flexibility of block catiomers could be an important parameter in the
formation of PIC nanostructures with siRNA, though its effect remains
unknown. Here, we studied the influence of block catiomer flexibility on
the assembly of PIC structures with siRNA using a complementary
polymeric system, i.e. poly(ethylene glycol)-poly(L-lysine) (PEG-PLL)
and PEG-poly(glycidylbutylamine) (PEG-PGBA), which has a relatively more
flexible polycation segment than PEG-PLL. Mixing PEG-PGBA with siRNA at
molar ratios of primary amines in polymer to phosphates in the siRNA
(N/P ratios) higher than 1.5 promoted the multimolecular association of
uPICs, whereas PEG-PLL formed uPIC at all N/P ratios higher than 1.
Moreover, uPICs from PEG-PGBA were more stable against counter polyanion
exchange than uPICs from PEG-PLL, probably due to a favorable
complexation process, as suggested by computational studies of
siRNA/block catiomer binding. In in vitro experiments, PEG-PGBA uPICs
promoted effective intracellular delivery of siRNA and efficient gene
knockdown. Our results indicate the significance of polycation
flexibility on assembling PIC structures with siRNA, and its potential
for developing innovative delivery systems.
Organic and inorganic mixed phase modification of a silver surface for
functionalization with biomolecules and stabilization of electromotive
force Tabata, M.; Kataoka-Hamai, C.; Nogami, K.; Tsuya, D.; Goda, T.; Matsumoto, A.; Miyahara, Y. RSC Adv.2021, 11(40), 24958-24967. Abstract
A solid-state potentiometric biosensor based on the organic and
inorganic mixed phase modification of a silver surface is proposed.
Stabilization of the electromotive force and functionalization with
biomolecules on the sensing surface were simultaneously achieved using
silver chloride chemically deposited with 1,3-diaminopropanetetraacetic
acid ferric ammonium salt monohydrate and a self-assembled monolayer
with oligonucleotide probes, respectively. The formation of silver
chloride and adsorption of alkanethiol on the silver surface were
confirmed with X-ray photoelectron spectroscopy. The resulting modified
surface reduced the nonspecific binding of interfering biomolecules and
achieved a high signal to noise ratio. The electromotive forces of the
modified silver thin film electrodes were stable under constant chloride
ion concentrations. Hybridization assays were performed to detect
microRNA 146. The lower limit of detection was 0.1 pM because of the
small standard deviation. The proposed biosensor could be useful as a
disposable single-use sensor in medical fields such as liquid biopsies.
Vascular Bursts Act as a Versatile Tumor Vessel Permeation Route for
Blood-Borne Particles and Cells Igarashi, K.; Cabral, H.; Hong, T.; Anraku, Y.; Mpekris, F.; Stylianopoulos, T.; Khan, T.; Matsumoto, A.; Kataoka, K.; Matsumoto, Y.; Yamasoba, T. Small2021, 17(42), 2103751. Abstract
The recent discovery of vascular bursts in tumor vasculature has sparked renewed interest in
active transport of sub-100 nm particles, highlighting the dynamic nature of its distribution. In this paper,
an even broader versatility of vascular burst transport is demonstrated through the validation of a library
of blood-borne particles together with mathematical model simulation to estimate the burst vent size.
Boronic Acid Ligands Can Target Multiple Subpopulations of Pancreatic Cancer Stem Cells via pH-Dependent Glycan-Terminal Sialic Acid Recognition Miyazaki, T.; Khan, T.; Tachihara, Y.; Itoh, M.; Miyazawa, T.; Suganami, T.; Miyahara, Y.; Cabral, H.; Matsumoto, A. ACS Appl. Bio Mater.2021, 4(9), 6647-6651. Abstract
Eradication of cancer stem cells (CSCs) is an ultimate goal in cancer chemotherapy. Although a ligand-assisted targeting approach seems rational, the existence of subpopulations of CSCs and their discrimination from those present on healthy sites makes it a severe challenge. Some boronic acid (BA) derivatives are known for the ability to bind with glycan-terminal sialic acid (SA), in a manner dependent on the acidification found in hypoxic tumoral microenvironment. Taking advantage of this feature, here we show that the BA–ligand fluorescence conjugate can effectively target multiple CSC subpopulations in parallel, which otherwise must be independently aimed when using antibody-ligands.
In-situ chemical modification of printed conducting polymer films
for specific glucose biosensing Fujisaki, H.; Watcharawittayakul, T.; Matsumoto, A.; Miyahara, Y.; Goda, T. Sens. Actuators B: Chem.2021, 349. Abstract
Conductive polymers, such as
poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS),
can be used for specific biosensing after its surface is modified with
functional groups. Herein, we report a simple two-step surface
modification method for commercially available PEDOT:PSS films printed
on a flexible substrate. The derivatization process involves: (1) the
introduction of an ethylenediamine linker for conjugation with the
biorecognition element by activating the sulfonate group in PSS with an
acid chloride reaction; and (2) the introduction of FPBA into the
ethylenediamine linker. As a proof of concept,
4-carboxy-3-fluorophenylboronic acid (carboxy FPBA) is covalently
introduced to the side chain of the PSS dopant in the conductive layer.
FPBA serves as a selective molecular recognition element for diol
compounds, including glucose, at neutral pH. Continuous glucose
monitoring is achieved by label-free potentiometry using
FPBA-functionalized commercial PEDOT:PSS films. Negative potential
responses with glucose are successfully achieved in ideal and realistic
buffer solutions with or without 1% fetal bovine serum (FBS) because of
the complexation of FPBA. The dynamic range of the enzyme-free sensor
covered physiologically relevant blood glucose levels of 70-140 mg/dL.
The developed method is suitable and cost effective for the mass
production of biosensors as it can be applied to a large surface area at
once. Furthermore, various ligands and receptors can be introduced onto
commercial PEDOT:PSS films using this technique. Hence, the proposed
method has potential applications in wearable and implantable
biosensors.
総説
ボロン酸ゲルを用いた糖尿病治療デバイスの社会実装 (Social implementation of diabetes treatment device using boronic acid gel) 松元 亮; 宮崎 拓也; 伊藤 美智子; 菅波 孝祥; 宮原 裕二. バイオマテリアル (Journal of Japanese Society for Biomaterials) 2021, 39(4), 252-257.
A boronate gel-based synthetic platform for closed-loop insulin delivery
systems Matsumoto, A.; Chen, S. Polym. J.2021, 53(12), 1305-1314. Abstract
Diabetes is one of the most devastating global diseases with an
ever-increasing number of patients. Achieving persistent glycemic
control in a painless and convenient way is an unmet goal for diabetes
management. Insulin therapy is commonly utilized for diabetes treatment
and usually relies on patient self-injection. This not only impairs a
patient’s quality of life and fails to precisely control the blood
glucose level but also brings the risk of life-threatening hypoglycemia.
“closed-loop” insulin delivery systems could avoid these issues by
providing on-demand insulin delivery. However, safety concerns limit the
application of currently developed electronics-derived or enzyme-based
systems. Phenylboronic acid (PBA), with the ability to reversibly bind
glucose and a chemically tailored binding specificity, has attracted
substantial attention in recent years. This focus review provides an
overview of PBA-based versatile insulin delivery platforms developed in
our group, including new PBA derivatives, glucose-responsive gels, and
gel-combined medical devices, with a unique “skin layer” controlled
diffusion feature.
Boronic acids (BA) are known for their ability to reversibly interact
with the diol groups, a common motif of biomolecules including sugars,
ribose, and catechols. One can tailor BAs to elicit a divergent profile
of binding strength and specificity on the basis of stereochemistry and
controlled electronic effects. This focus review provides an overview of
a phenylboronic acid (PBA)-based, totally synthetic platform for insulin
delivery applications developed in our group, with focuses on the
development of new PBA derivatives, glucose-responsive gels, and the
gel-combined medical devices.
マクロファージにおける脂質代謝障害に着目したNASH発症機構の解明 (Elucidation of the mechanism of NASH onset focusing on lipid metabolic disorders in macrophages) 伊藤 美智子; 金井 紗綾香; 田村 篤志; 白川 伊吹; 金森 耀平; 田中 都; 松元 亮; 宮原 裕二; 小川 佳宏; 菅波 孝祥. 日本内分泌学会雑誌 (Journal of the Japanese Endocrine Society) 2021, 97(1), 282.
2020
Direct Observation of Cell Surface Sialylation by Atomic Force
Microscopy Employing Boronic Acid-Sialic Acid Reversible Interaction Osawa, S.; Matsumoto, A.; Maejima, Y.; Suzuki, T.; Miyahara, Y.; Otsuka, H. Anal. Chem.2020, 92(17), 11714-11720. Abstract
Tracing cell surface sialylation dynamics at a scale of the
glycolipoprotein microdomain (lipid rafts) formations remains an
intriguing challenge of cellular biology. Here, we demonstrate that this
goal is accessible, taking advantage of a boronic acid (BA)-based
reversible molecular recognition chemistry. A BA-end-functionalized
poly(ethylene glycol) was decorated onto an atomic force microscopy
(AFM) cantilever, which provided a dynamic and sialic acid (SA)-specific
imaging mode. Using this technique, we were able to heat map the SA
expression levels not only on protein-decorated substrates but also
directly on the cell surfaces, with a submicrometer scale resolution
that may be relevant to that of the lipid rafts formation. The SA
specificity and the binding reversibility of the probe were confirmed
from its pH-dependent characteristics and an inhibition assay using free
state SA. This finding may provide a noninvasive means for assessing a
variety of SA-involved glycosylation dynamics spanning from physiology
to pathology.
Temperature-Stable Boronate Gel-Based Microneedle Technology for
Self-Regulated Insulin Delivery Chen, S.; Miyazaki, T.; Itoh, M.; Matsumoto, H.; Moro-oka, Y.; Tanaka, M.; Miyahara, Y.; Suganami, T.; Matsumoto, A. ACS Appl. Polym. Mater.2020, 2(7), 2781-2790. Abstract/Cover
Insulin delivery in a self-regulated and painless way to tightly control
the glycemic level is highly demanded for diabetes treatment.
Phenylboronic acid (PBA) has gained great research interests due to its
synthetic nature and reversible binding capability with glucose. A
totally synthetic smart PBA hydrogel exhibiting efficient glucose
sensitivity at physiological pH and temperature has been previously
developed. However, its clinical applications may be hampered by the
temperature-dependent release profile. Herein, we report a
glucose-responsive, temperature-stable, boronate-containing hydrogel
with optimized formulation and its fabrication into a microneedle (MN)
patch to provide on-demand and convenient insulin delivery. The
resulting MN patch displayed temperature-independent and
glucose-responsive insulin release in a rapid and sustained manner
through the regulation by the “skin layer” formed on the surface.
This MNs patch can effectively penetrate the skin and was highly
biocompatible. Compared to the majority of the glucose-responsive MN
patches capitalizing on glucose oxidase and nanoparticles, this totally
synthetic, protein-free, and nanoparticle-free MN patch could eliminate
the safety concerns and provide the sustainability and advantage for
large-scale production.
Hollow fiber-combined glucose-responsive gel technology as an in vivo
electronics-free insulin delivery system Matsumoto, A.; Kuwata, H.; Kimura, S.; Matsumoto, H.; Ochi, K.; Moro-oka, Y.; Watanabe, A.; Yamada, H.; Ishii, H.; Miyazawa, T.; Chen, S.; Baba, T.; Yoshida, H.; Nakamura, T.; Inoue, H.; Ogawa, Y.; Tanaka, M.; Miyahara, Y.; Suganami, T. Commun. Biol.2020, 3(313). AbstractPress release
Accumulating evidence demonstrates that not only sustained elevation of
blood glucose levels but also the glucose fluctuation represents key
determinants for diabetic complications and mortality. Current
closed-loop insulin therapy option is limited to the use of
electronics-based systems, although it poses some technical issues with
high cost. Here we demonstrate an electronics-free, synthetic boronate
gel-based insulin-diffusion-control device technology that can cope with
glucose fluctuations and potentially address the electronics-derived
issues. The gel was combined with hemodialysis hollow fibers and scaled
suitable for rats, serving as a subcutaneously implantable,
insulin-diffusion-active site in a manner dependent on the subcutaneous
glucose. Continuous glucose monitoring tests revealed that our device
not only normalizes average glucose level of rats, but also markedly
ameliorates the fluctuations over timescale of a day without inducing
hypoglycemia. With inherent stability, diffusion-dependent scalability,
and week-long & acute glucose-responsiveness, our technology may offer
a low-cost alternative to current electronics-based approaches.
Here, the authors develop an in vivo insulin delivery system which
consists of a glucose responsive gel combined with hemodialysis hollow
fibers. This system is electronics-free, temperature independent, and
can stably sustain acute glucose-responsiveness in rats.
C-type lectin Mincle mediates cell death-triggered inflammation in acute
kidney injury Tanaka, M.; Saka-Tanaka, M.; Ochi, K.; Fujieda, K.; Sugiura, Y.; Miyamoto, T.; Kohda, H.; Ito, A.; Miyazawa, T.; Matsumoto, A.; Aoe, S.; Miyamoto, Y.; Tsuboi, N.; Maruyama, S.; Suematsu, M.; Yamasaki, S.; Ogawa, Y.; Suganami, T. J. Exp. Med.2020, 217(11), e20192230. Abstract
Accumulating evidence indicates that cell death triggers sterile
inflammation and that impaired clearance of dead cells causes
nonresolving inflammation; however, the underlying mechanisms are still
unclear. Here, we show that macrophage-inducible C-type lectin (Mincle)
senses renal tubular cell death to induce sustained inflammation after
acute kidney injury in mice. Mincle-deficient mice were protected
against tissue damage and subsequent atrophy of the kidney after
ischemia-reperfusion injury. Using lipophilic extract from the injured
kidney, we identified beta-glucosylceramide as an endogenous Mincle
ligand. Notably, free cholesterol markedly enhanced the agonistic effect
of beta-glucosylceramide on Mincle. Moreover, beta-glucosylceramide and
free cholesterol accumulated in dead renal tubules in proximity to
Mincle-expressing macrophages, where Mincle was supposed to inhibit
clearance of dead cells and increase proinflammatory cytokine
production. This study demonstrates that beta-glucosylceramide in
combination with free cholesterol acts on Mincle as an endogenous ligand
to induce cell death-triggered, sustained inflammation after acute
kidney injury.
Structural Control of Boronic Acid Ligands Enhances Intratumoral Targeting of Sialic Acid To Eradicate Cancer Stem-like Cells Khan, T.; Igarashi, K.; Tanabe, A.; Miyazawa, T.; Fukushima, S.; Miura, Y.; Matsumoto, Y.; Yamasoba, T.; Matsumoto, A.; Cabral, H.; Kataoka, K. ACS Appl. Bio Mater.2020, 3(8), 5030-5039. Abstract
Aberrant sialylation of cancer cells is emerging as an attractive method for generating effective antitumor strategies.
However, as sialic acid (SA) is also present in healthy tissues, systems targeting SA in tumors must be strategically designed
to be specifically activated in an intratumoral environment while avoiding systemic interaction. Phenylboronic acid (PBA)
and its derivatives have shown potential for developing such smart ligands based on its triggered binding to SA at
intratumoral pH. Because the affinity of PBAs against SA can be structurally controlled, the approach may further
offer the possibility to enhance tumor targeting by molecularly engineering PBAs. Thus, to demonstrate that the modification
of the chemical structure of PBAs can promote tumor targeting, we compared nanomedicines installed with the standard PBA or
5-boronopicolinic acid (5-BPA), which shows an exceptionally high binding affinity to SA in acidic pH. Platinum anticancer drugs
were loaded into these nanomedicines and evaluated against orthotopic head and neck tumors, featuring a large fraction of SA-rich
cancer stem-like cells (CSCs) that are resistant to platinum drugs. The 5-BPA ligands increased intracellular drug delivery of
nanomedicines at intratumoral pH (pH 6.5) and enhanced the accumulation of nanomedicines in tumors to efficaciously eliminate
the malignant CSCs, suppress tumor growth, and prolong mice survival. These findings indicate the potential of engineered PBA
ligands for developing effective strategies targeting SA in tumors.
Guanidine-phosphate interactions stabilize polyion complex micelles
based on flexible catiomers to improve mRNA delivery Miyazaki, T.; Uchida, S.; Hatano, H.; Miyahara, Y.; Matsumoto, A.; Cabral, H. Eur. Polym. J.2020, 140, 110028. Abstract
Messenger RNA (mRNA) holds great potential as therapeutic agent, though
its broad applicability is hampered by its rapid degradation by nuclease
attacks and poor access to cells. Polyion complex (PIC) micelles
comprising block catiomers are promising mRNA carriers, because of their
effective mRNA protection in the PIC core and the capability to promote
mRNA cellular uptake. We have recently shown that flexible polycations
can promote the interaction between catiomers and mRNA toward improving
delivery efficiency, demonstrating that, by engineering the PIC
formation, the efficacy of mRNA-loaded PIC micelles (mRNA/m) can be
improved. Herein, we focused on the valency between the polycation
segment and mRNA, and studied its ability to promote, in collaboration
with the flexible catiomers, mRNA stability and delivery efficiency for
producing potent nanocarriers. The functionalities of guanidine and
primary amine were compared through preparation of two different block
copolymers, namely, poly(ethylene glycol)-poly(glycidyl methyl
guanidine) (PEG-PGMG) and PEG-poly(glycidyl methyl amine (PEG-PGMA)).
mRNA/m from PEG-PGMG (mRNA/mPGMG) showed enhanced stability against
biological molecules, including polyanions, urea and nucleases compared
to mRNA/m prepared from PEG-PGMA (mRNA/mPGMA), resulting in high
efficiency of cellular uptake and protein translation. Our results
indicate that multivalent interactions between the guanidine moieties in
the polycation segments of block copolymers and the phosphate groups in
mRNA are a key factor for stabilizing mRNA/m toward improving mRNA
delivery efficiency.
2019
Microneedle-Array Patch Fabricated with Enzyme-Free Polymeric Components
Capable of On-Demand Insulin Delivery Chen, S.; Matsumoto, H.; Moro-oka, Y.; Tanaka, M.; Miyahara, Y.; Suganami, T.; Matsumoto, A. Adv. Funct. Mater.2019, 29(7). Abstract/CoverVideo abstractPress release
Achieving persistent glycemic control in a painless and convenient way
is the ultimate goal of diabetes management. Herein, an enzyme-free
polymeric microneedle (MN)-array patch composed of a boronate-containing
hydrogel semi-interpenetrated by biocompatible silk fibroin is
developed. Consistent with the previous reports, the presence of the
boronate-hydrogel allows for glucose-responsive diffusion-control of
insulin, while the crystalline fibroin component serves as a
matrix-stiffener to validate skin penetration. Remarkably, this
enzyme-free smart artificial on-skin pancreas prototype remains stable
for at least 2 months in an aqueous environment. Furthermore, it
establishes sustained as well as acute glucose-responsive insulin
delivery, and is to the authors’ knowledge, the first successful
material design addressing such two technical challenges at once on an
MN format. This long-acting, on-demand insulin delivery technology may
offer a candidate for a next-generation diabetes therapy that is
remarkably stable, safe, economically efficient, and capable of
providing both acute- and continuous glycemic control in a manner
minimally dependent on patient compliance.
Induced Proton Perturbation for Sensitive and Selective Detection of
Tight Junction Breakdown Hatano, H.; Goda, T.; Matsumoto, A.; Miyahara, Y. Anal. Chem.2019, 91(5), 3525-3532. Abstract/Cover
Tight junctions (TJs) in the epithelial cell gap play primary roles in
body defense and nutrient absorption in multicellular organisms.
Standard in vitro assays lack sensitivity, selectivity, temporal
resolution, and throughput for bioengineering applications. Prompted by
the rigorous barrier functions of TJ, we developed a TJ assay that
senses proton leaks in the cell gap using ion-sensitive field-effect
transistors. Upon exposure of Madin-Darby canine kidney (MDCK) cells
cultured on a gate dielectric to a calcium-chelator EGTA,
ammonia-assisted pH perturbation was enhanced solely in TJ-forming
cells. This was supported by simulations with increased ion permeability
in the paracellular pathway. Following administration of Clostridium
perfringens enterotoxin as a specific TJ inhibitor to the MDCK cells,
our method detected TJ breakdown at a 13X lower concentration than a
conventional trans-epithelial electrical resistance assay. Thus, the
semiconductor-based active pH sensing could offer an alternative to
current in vitro assays for TJs in pathological, toxicological, and
pharmaceutical studies.
Translocation Mechanisms of Cell-Penetrating Polymers Identified by
Induced Proton Dynamics Goda, T.; Imaizumi, Y.; Hatano, H.; Matsumoto, A.; Ishihara, K.; Miyahara, Y. Langmuir2019, 35(24), 8167-8173. Abstract
Unlike the majority of nanomaterials designed for cellular uptake via
endocytic pathways, some of the functional nanoparticles and nanospheres
directly enter the cytoplasm without overt biomembrane injuries.
Previously, we have shown that a water-soluble nanoaggregate composed of
amphiphilic random copolymer of 2-methacryloyloxyethyl phosphorylcholine
(MPC) and n-butyl methacrylate (BMA), poly(MPC-random-BMA) (PMB), passes
live cell membranes in an endocytosis-free manner. Yet, details in its
translocation mechanism remain elusive due to the lack of proper
analytical methods. To understand this phenomenon experimentally, we
elaborated the original pH perturbation assay that is extremely
sensitive to the pore formation on cell membranes. The ultimate
sensitivity originates from the detection of the smallest indicator H+
(H3O+) passed through the molecularly sized transmembrane pores upon
challenge by exogenous reagents. We revealed that water-soluble PMB at
the 30 mol % MPC unit (i.e., PMB30W) penetrated into the cytosol of
model mammalian cells without any proton leaks, in contrast to
conventional cell-penetrating peptides, TAT and R8 as well as the
surfactant, Triton X-100. While exposure of PMB30W permeabilized
cytoplasmic lactate dehydrogenase out of the cells, indicating the
alteration of cell membrane polarity by partitioning of amphiphilic
PMB30W into the lipid bilayers. Nevertheless, the biomembrane
alterations by PMB30W did not exhibit cytotoxicity. In summary,
elucidating translocation mechanisms by proton dynamics will guide the
design of nanomaterials with controlled permeabilization to cell
membranes for bioengineering applications.
Induced Proton Dynamics on Semiconductor Surfaces for Sensing Tight
Junction Formation Enhanced by an Extracellular Matrix and Drug Hatano, H.; Goda, T.; Matsumoto, A.; Miyahara, Y. ACS Sens.2019, 4(12), 3195-3202. Abstract
In the fields of tissue engineering and drug discovery, confirming the
formation and maturation of epithelial cell tight junctions (TJs), which
are necessary for blocking pathogenic invasion and absorption of
nutrients and ions, at a high spatiotemporal resolution is essential. We
previously developed a system of monitoring pH perturbation induced by
weak acid exposure to cells cultured on an ion-sensitive field-effect
transistor that enables a sensitive and specific detection of
biomembrane injuries and TJ breakdowns caused by external stimuli such
as nanomaterials and cytotoxins. In this study, we monitor time-lapse
changes in the paracellular diffusion of growing epithelial cell
monolayers using the pH perturbation assay as well as conventional
permeability and trans-epithelial electrical resistance assays. The
effects of the extracellular matrix and a TJ potentiator (KN-93) on
epithelial TJ formation are evaluated. TJ formations were promoted on
the substrate coated with Matrigel more than on the one coated with
poly(L-lysine). KN-93 accelerated TJ formations in a dose-dependent
manner. The pH perturbation assay denoted a longer incubation time for
the completion of TJ formation compared with the conventional assays
under the same conditions. Importantly, the pH perturbation assay is
able to rigorously evaluate TJ formation, as the assay uses protons as
the smallest indicator for detecting paracellular gaps, and the pH
perturbation is specific to TJ alterations. These features for in vitro
TJ evaluation using proton dynamics are advantageous for applications in
tissue engineering and drug development.
Gold Nanoparticles with Ligand/Zwitterion Hybrid Layer for Individual
Counting of Influenza A H1N1 Subtype Using Resistive Pulse Sensing Horiguchi, Y.; Goda, T.; Matsumoto, A.; Takeuchi, H.; Yamaoka, S.; Miyahara, Y. Langmuir2019, 35(5), 1798-1806. Abstract
Resistive pulse sensing (RPS) is an analytical technique for detecting
particles with nano- to micrometer diameters, such as proteins, viruses,
and bacteria. RPS is a promising tool for diagnosis as it can analyze
the characteristics of target particles individually from ion current
blockades as pulse waveforms. However, it is difficult to discriminate
analog targets because RPS merely provides physical information such as
size, shape, concentration, and charge density of the analyte. Influenza
A virus, which is 80-120 nm in diameter, has various subtypes,
demonstrating the diversity of virus characteristics. For example,
highly pathogenic avian influenza infections in humans are recognized as
an emerging infectious disease with high mortality rates compared with
human influenza viruses. Distinguishing human from avian influenza using
their differing biological characteristics would be challenging using
RPS. To develop a highly selective diagnostic system for infectious
diseases, we combined RPS with molecular recognition. Gold nanoparticles
(GNPs) that have human influenza A (H1N1 subtype) virus-specific sialic
acid receptors on the surface were prepared as a virus label for RPS
analysis. A sulfobetaine and sialic acid (ligand) hybrid surface was
formed on the GNPs for the suppression of nonspecific interaction. The
results show a size change of viruses derived from specific interactions
with GNPs. In contrast, no size shift was observed when nonspecific
sialic acid receptor immobilized GNPs were used. Detection of viruses by
individual particle counting could be a new facet of diagnosis.
Smart Microneedle Fabricated with Silk Fibroin Combined Semi
interpenetrating Network Hydrogel for Glucose-Responsive Insulin
Delivery Chen, S.; Matsumoto, H.; Moro-oka, Y.; Tanaka, M.; Miyahara, Y.; Suganami, T.; Matsumoto, A. ACS Biomater. Sci. Eng.2019, 5(11), 5781-5789. Abstract
Microneedle (MN) technology, which can transdermally deliver insulin in
a noninvasive manner, offers a promising way to replace subcutaneous
self-injection for diabetes management. Hydrogel is an attractive
candidate for MN fabrication because of its biocompatibility,
controllable degradability, and possibility to achieve sustained as well
as stimuli-responsive drug delivery. Herein, we report a smart MN
composed of a semi-interpenetrating network (semi-IPN) hydrogel prepared
by biocompatible silk fibroin (SF) and phenylboronic acid/acrylamide for
glucose-responsive insulin delivery. Six fabrication methods were
investigated to maintain the glucose sensitivity of the hydrogel while
avoiding deformation during fabrication. The optimized method was to
fabricate smart MNs using a two-layer strategy, with a needle region
formed by the SF combined semi-IPN hydrogel and the base layer
fabricated by SF. The hybrid MN autonomously released insulin
well-correspondent to the glucose change pattern via the regulation of
the skin layer formed on the surface. Furthermore, this hybrid MN
retained its original needle shape after 1 week in aqueous system, thus
eliminating the safety concerns associated with dissolving MNs and
suggesting the possibility for sustained delivery. This nondegradable
smart MN is promising to provide on-demand insulin in a long-acting,
painless, and convenient way.
Field-effect transistor array modified by a stationary phase to generate
informative signal patterns for machine learning-assisted recognition of
gas-phase chemicals Yoshizumi, T.; Goda, T.; Yatabe, R.; Oki, A.; Matsumoto, A.; Oka, H.; Washio, T.; Toko, K.; Miyahara, Y. Mol. Syst. Des. Eng.2019, 4(2), 386-389. Abstract
We propose an artificial intelligence-based chemical-sensing system
integrating a porous gate field-effect transistor (PGFET) array modified
by gas chromatography stationary phase materials and machine-learning
techniques. The chemically sensitive PGFET array generates
cross-reactive signals for computational analysis and shows potential
for applications to compact intelligent sensing devices, including
mobile electronic noses.
Determination of cellular vitamin C dynamics by HPLC-DAD Miyazawa, T.; Matsumoto, A.; Miyahara, Y. Analyst2019, 144(11), 3483-3487. Abstract/Cover
A redox-sensitive inter-conversion between ascorbic acid (ASC) and its
oxidized form dehydroascorbic acid (DHA) in the intracellular
environment has been of exceptional interest to recent metabolomics and
pharmaceutical research. We developed a chromatographic protocol to
instantly determine these vitamers with each identity from cellular
extracts, without any labeling and pretreatments. Owing to its
simplicity, one can readily continue the assay for hours, an otherwise
difficult to cover timescale at which the intracellular DHA-ASC
conversion comes into play. The method was validated for the analysis of
pancreatic cancer cells, to our knowledge the first-ever study on a
nucleated cell type, to trace in detail their kinetics of glucose
transporter-dependent DHA uptake and, simultaneously, that for the
intracellular ASC conversion. The simplest of all the relevant
techniques and yet with the unique ability to provide each vitamer
identity on a high-throughput basis, this method should offer the most
practical option for VC-involved physiological and pharmaceutical
studies including high-dose VC cancer therapy.
総説
ボロノレクチンを利用したバイオエンジニアリング (Bioengineering using ’Borono-Lectin’) 松元 亮; 宮原 裕二. 医学のあゆみ (History of Medicine) 2019, 269(9), 697-702 (医歯薬出版株式会社). Abstract
「ボロノレクチン」工学が拓く新しい治療オプション (New treatment options developed through ’Borono-Lectin’ engineering) 松元 亮; 菅波 孝祥; 宮原 裕二. MDB技術予測レポート ~2050年未来・世界を変える技術~ (MDB Technology Forecast Report - Technology that will change the future and the world in 2050) 2019, (株式会社日本能率協会総合研究所マーケティング・データ・バンク (MDB)).
Determination of Intra- and Extra-cellular Vitamin C Dynamics Miyazawa, T.; Matsumoto, A.; Miyahara, Y. G.I.T. Laboratory Journal2019. Abstract
The redox-sensitive inter-conversion of ascorbic acid (ASC) and its oxidized form dehydroascorbic acid (DHA) in intracellular and extracellular environments is of exceptional interest at the forefront of metabolomics and pharmaceutical research, including high-dose vitamin C cancer therapy. A chromatographic protocol to instantly determine these vitamers in both forms from cellular extracts, without any labeling or pretreatment has been reported earlier.
人工膵臓様デバイスによる血糖管理の未来 (The future of blood sugar management with artificial pancreas-like devices) 木村 真一郎; 田中 都; 松元 亮; 菅波 孝祥. Pharma Medica2019, 37(12), 59-62.
Biomaterials Science and Engineering in Japan: Attractive,
Multidisciplinary, and Essential Research Field in Japan Matsumoto, A.; Numata, K. ACS Biomater. Sci. Eng.2019, 5(11), 5559-5560.
’エレクトロニクスフリー’で完全合成型の人口膵臓の開発 (Development of electronics-free and completely synthetic artificial pancreas) 松元 亮. バイオサイエンスとインダストリー (B&I) (Bioscience and Industry) 2019, 77(3), 256-257.
2018
Enhanced Intracellular Delivery of siRNA by Controlling ATP-Responsivity
of Phenylboronic Acid-Functionalized Polyion Complex Micelles Naito, M.; Yoshinaga, N.; Ishii, T.; Matsumoto, A.; Miyahara, Y.; Miyata, K.; Kataoka, K. Macromol. Biosci.2018, 18(1), 1700357. Abstract
Intracellular delivery of small interfering RNA (siRNA) is a
long-standing challenge in oligonucleotide therapeutics. Herein,
adenosine triphosphate (ATP)-responsive polyion complex micelles
assembled from poly(ethylene glycol)-block-poly(l-lysine) (PEG-PLys)
bearing 4-carboxy-3-fluorophenylboronic acid (FPBA) moiety in the PLys
side chains (FPBA micelle) for the delivery of cholesterol-modified
siRNA (Chol-siRNA) are described. The pKa of FPBA moiety is 7.2 and,
therefore, it exists in equilibrium between negatively charged
tetravalent and noncharged hydrophobic trivalent forms in physiological
pH conditions. Each form cooperatively stabilizes the micelle in
distinct modes, that is, a covalent ester-linkage between charged
boronate and ribose functionality at 3’ ends of Chol-siRNA and a
hydrophobic interaction between noncharged boronic acid and Chol-siRNA.
When exposed to ATP at a concentration associated with the intracellular
environment, the Chol-siRNA/ boronate linkage is readily cleaved to
facilitate the release of Chol-siRNA into cytoplasm. In order to further
optimize this switching capability, the effect of FPBA modification rate
is studied for the resulting ATP-responsive behavior of the micelles. As
a result, the range of 23-35% in the modification rate is found
suitable to maximize the gene silencing efficiency, demonstrating the
potential of the FPBA-modified micelles as ATP-responsive smart siRNA
carrier systems.
Characterization and Optimization of Thermally Grown Iridium Oxide and
Its Application to pH Sensors Ratanaporncharoen, C.; Tabata, M.; Watanagool, N.; Goda, T.; Matsumoto, A.; Sriyudthsak, M.; Miyahara, Y. Sens. Mater.2018, 30(5), 1175-1185. Abstract
In this study, we evaluate the thermal oxidization methods of iridium to
simplify the fabrication of Ir/IrOx pH microsensors. Iridium oxide
(IrOx) is a typical pH-sensing material. Specifically, three parameters
of the previously reported “carbonate-melt” method are modified,
namely, the oxidization temperature, oxidization time, and annealing
process after oxidization. Then, we compare the characteristics of the
fabricated sensors (i.e., the initial pH responsivity, time required to
reach the steady state, and potential drift). The pH response depends on
oxidization temperature and time.
Human influenza virus detection using sialyllactose-functionalized
organic electrochemical transistors Hai, W.; Goda, T.; Takeuchi, H.; Yamaoka, S.; Horiguchi, Y.; Matsumoto, A.; Miyahara, Y. Sens. Actuator B-Chem.2018, 260, 635-641. Abstract
An organic electrochemical transistor (OECT) with a
trisaccharide-grafted conductive polymer channel was developed for human
influenza A virus detection under aqueous conditions. A target
recognition element was introduced into the electrochemical amplifier of
the OECT for highly sensitive, selective, and label-free virus sensing.
3,4-Ethylenedioxythiophene (EDOT) and its derivative bearing an
oxylamine moiety (EDOTOA) were electrochemically copolymerized on the
channel region composed of a PEDOT:PSS thin film. The trisaccharides
composed of Sia-alpha 2,6’-Gal-Glu (2,6-sialyllactose), a specific
receptor for the hemagglutinin used as a spike protein on the surface of
human influenza A virus, were covalently introduced into the EDOTOA
unit. Changes in the drain current of the OECT were observed following
virus adsorption onto the 2,6-sialyllactose-functionalized channel. A
signal transduction mechanism involving a doping effect due to the
adsorption of negatively-charged virus nanoparticles is proposed. The
limit of detection was more than two orders of magnitude lower than
commercial immunochromatographic influenza virus assays over the same
detection time. Because of its processability with printing technologies
and low power consumption, the OECT device developed here may be
suitable for the wearable monitoring of influenza virus infection. (C)
2018 Elsevier B.V. All rights reserved.
pH Mapping on Tooth Surfaces for Quantitative Caries Diagnosis Using
Micro Ir/IrOx pH Sensor Ratanaporncharoen, C.; Tabata, M.; Kitasako, Y.; Ikeda, M.; Goda, T.; Matsumoto, A.; Tagami, J.; Miyahara, Y. Anal. Chem.2018, 90(7), 4925-4931. Abstract
A quantitative diagnostic method for dental caries would improve oral
health, which directly affects the quality of life. Here we describe the
preparation and application of Ir/IrOx pH sensors, which are used to
measure the surface pH of dental caries. The pH level is used as an
indicator to distinguish between active and arrested caries. After a
dentist visually inspected and defined 18 extracted dentinal caries at
various positions as active or arrested caries, the surface pH values of
sound and caries areas were directly measured with an Ir/IrOx pH sensor
with a diameter of 300 mu m as a dental explorer. The average pH values
of the sound root, the arrested caries, and active caries were 6.85,
6.07, and 5.30, respectively. The pH obtained with an Ir/IrOx sensor was
highly correlated with the inspection results by the dentist, indicating
that the types of caries were successfully categorized. This caries
testing technique using a micro Ir/IrOx pH sensor provides an accurate
quantitative caries evaluation and has potential in clinical diagnosis.
Gas-sensitive Field-effect Transistor Incorporating Polymer Layer and
Porous Metal Electrode in the Gate Structure Yoshizumi, T.; Goda, T.; Matsumoto, A.; Miyahara, Y. Sens. Mater.2018, 30(5, 1), 1001-1008. Abstract
Field-effect transistor (FED-based sensors have attractive potential for
use in fabricating miniaturized sensor arrays by semiconductor
processes. In this work, a gas-sensitive FET incorporating a
polyethylene glycol (PEG) film and porous Pt electrode in the gate
structure is proposed. In this new type of gas-sensitive FET, the PEG
layer provides a dielectric layer (i.e., a stationary phase) that
interacts with gaseous molecules, while the porous Pt gate electrode
allows gaseous molecules to effectively access the PEG layer. Features
of the response pattern, such as peak height, recovery time, and peak
shape, unique to the PEG-modified FET sensor were observed when exposed
to vapor of volatile organic compounds (VOCs). The sensing mechanism of
the gas-sensitive FET is discussed in terms of capacitance changes of
the gate structure induced by gaseous molecule adsorption onto the
stationary phase. A variety of polymeric materials might be used to
modify the gate, and the proposed structure shows promise as a platform
for cross-reactive FET-based gas sensor arrays for pattern recognition.
総説
困難な人工すい臓を実現した, 研究者の好奇心とは (What was the researcher’s curiosity that made the difficult artificial pancreas possible?) 松元 亮. 今日の健康 (Health Today) 2018, 2, 130-131.
著書
グルコース応答性ポリマーの設計と医療応用 (Design and medical applications of glucose-responsive polymers) 松元 亮; 菅波 孝祥; 宮原 裕二. 刺激応答性高分子ハンドブック ~分子応答性~ (Stimulus-responsive polymer handbook - Molecular responsiveness) 2018, Chapter 5.2, 678-684 (NTS Inc.).
2017
Proton-sensing transistor systems for detecting ion leakage from plasma
membranes under chemical stimuli Imaizumi, Y.; Goda, T.; Schaffhauser, D. F.; Okada, J.; Matsumoto, A.; Miyahara, Y. Acta Biomater.2017, 50, 502-509. Abstract
The membrane integrity of live cells is routinely evaluated for
cytotoxicity induced by chemical or physical stimuli. Recent progress in
bioengineering means that high-quality toxicity validation is required.
Here, we report a pH-sensitive transistor system developed for the
continuous monitoring of ion leakage from cell membranes upon challenge
by toxic compounds. Temporal changes in pH were generated with high
reproducibility via periodic flushing of HepG2 cells on a gate insulator
of a proton-sensitive field-effect transistor with isotonic buffer
solutions with without NH4Cl. The pH transients at the point of NH4Cl
addition/withdrawal originated from the free permeation of NH3 across
the semi-permeable plasma membranes, and the proton sponge effect
produced by the ammonia equilibrium. Irreversible attenuation of the pH
transient was observed when the cells were subjected to a membrane-toxic
reagent. Experiments and simulations proved that the decrease in the pH
transient was proportional to the area of the ion-permeable pores on the
damaged plasma membranes. The pH signal was correlated with the degree
of hemolysis produced by the model reagents. The pH assay was sensitive
to the formation of molecularly sized pores that were otherwise not
measurable via detection of the leakage of hemoglobin, because the
hydrodynamic radius of hemoglobin was greater than 3.1 nm in the
hemolysis assay. The pH transient was not disturbed by inherent
ion-transporter activity. The ISFET assay was applied to a wide variety
of cell types. The system presented here is fast, sensitive, practical
and scalable, and will be useful for validating cytotoxins and
nanomaterials.
Direct and label-free influenza virus detection based on multisite
binding to sialic acid receptors Horiguchi, Y.; Goda, T.; Matsumoto, A.; Takeuchi, H.; Yamaoka, S.; Miyahara, Y. Biosens. Bioelectron.2017, 92, 234-240. Abstract
A system to discriminate human or avian influenza A remains a highly
sought-after tool for prevention of influenza pandemics in humans.
Selective binding of the influenza A viral hemagglutinin (HA) to
specific sialic acid (SA) receptors (Neu5Ac alpha(2-6)Gal in humans,
Neu5Ac alpha(2-3)Gal in birds) is determined by the genotype of the HA
and neuraminidase (NA) segments, making it one of the key
characteristics that distinguishes human or avian influenza A virus.
Here we demonstrate the direct detection of whole H1N1 influenza A virus
using 6’-sialyllactose (Neu5Ac alpha(2-6)Gal beta(1-4)G1c,
6SL)-immobilized gold electrodes as biosensing surfaces. The sensitivity
was higher than that of conventional immunochromatographic technique
(ICT) for influenza virus and not restricted by genetic drift. The
label-free detection technology via direct attachment of a whole virus
using a chemically modified electrode is a promising means to provide a
simple and rapid diagnostic system for viral infections.
Heterocyclic boronic acids display sialic acid selective binding in a
hypoxic tumor relevant acidic environment Matsumoto, A.; Stephenson-Brown, A. J.; Khan, T.; Miyazawa, T.; Cabral, H.; Kataoka, K.; Miyahara, Y. Chem. Sci.2017, 8(9), 6165-6170. Abstract
Boronic acids are well known for their ability to reversibly interact
with the diol groups found in sugars and glycoproteins. However, they
are generally indiscriminate in their binding. Herein we describe the
discovery of a group of heterocyclic boronic acids demonstrating
unusually high affinity and selectivity for sialic acids (SAs or
N-acetylneuraminic acid), which are sugar residues that are intimately
linked with tumor growth and cancer progression. Remarkably, these
interactions strengthen under the weakly acidic pH conditions associated
with a hypoxic tumoral microenvironment. In vitro competitive binding
assays uncovered a significantly higher ability of 5-boronopicolinic
acid, one of the derivatives identified in this work as a strong
SA-binder, to interact with cell surface SA in comparison to a
gold-standard structure, 3propionamidophenylboronic acid, which has
proven to be an efficient SA-binder in numerous reports. This structure
also proved to be suitable for further chemical conjugation with a
well-preserved SA binding capability. These findings suggest an
attractive alternative to other ongoing boronic acid based chemistry
techniques aiming to achieve tumor-specific chemotherapies and
diagnoses.
Specific Recognition of Human Influenza Virus with PEDOT Bearing Sialic
Acid-Terminated Trisaccharides Hai, W.; Goda, T.; Takeuchi, H.; Yamaoka, S.; Horiguchi, Y.; Matsumoto, A.; Miyahara, Y. ACS Appl. Mater. Interfaces2017, 9(16), 14162-14170. Abstract
Conducting polymers are good candidates for biosensor applications when
molecular recognition element is imparted. We developed
trisaccharide-grafted conducting polymers for label-free detection of
the human influenza A virus (H1N1) with high sensitivity and
specificity. A 3,4-ethylenedioxythiophene (EDOT) derivative bearing an
oxylamine moiety was electrochemically copolymerized with EDOT. The
obtained film was characterized by cyclic voltammetry, X-ray
photoelectron spectroscopy, scanning electron microscopy, stylus surface
profilometer, and AC-impedance spectroscopy. The trisaccharides
comprising Sia-alpha 2,6’-Gal-Glu (2,6-sialyllactose) or Sia-alpha
2,3’-Gal-Glu (2,3sialyllactose) were covalently introduced to the side
chain of the conducting polymers as a ligand for viral recognition.
Immobilization of sialyllactose was confirmed by quartz crystal
microbalance (QCM) and water contact angle measurements. Specific
interaction of 2,6-sialyllactose with hemagglutinin in the envelope of
the human influenza A virus (H1N1) was detected by QCM and potentiometry
with enhanced sensitivity by 2 orders of magnitude when compared with
that of commercially available kits. The developed conducting polymers
possessing specific virus recognition are a good candidate material for
wearable monitoring and point-of-care testing because of their
processability and mass productivity in combination with printing
Demonstration of thermo-sensitive tetra-gel with implication for facile
and versatile platform for a new class of smart gels Matsumoto, A.; Sato, S.; Sakamaki, T.; Sanjo, M.; Tabata, M.; Goda, T.; Asoh, T.-A.; Kikuchi, A.; Miyahara, Y. J. Biomater. Sci.-Polym. Ed.2017, 28(10-12), 1000-1009. Abstract
A tertiary branched poly(N-isopropylacrylamide) with controlled
molecular weight, distribution and the end amino-functionalization
(tetra-PNIPAAm-NH2) was studied for the ability to form a gel via in
situ chain-end reaction with a counterpart tertiary branched
poly(ethyleneglycol) bearing N-hydroxysuccinimide end groups
(tetra-PEG-NHS), a well-documented class of building block to yield the
tetra-gel. Some of these polymers, both comparable and distinct
(relative to the counterpart) extended chain length pairs, provided a
self-standing and macroscopically homogeneous gel, which was capable of
undergoing thermo-sensitive and reversible change in hydration in line
with the nature of PNIPAAm. Phantom network model based calculation
indicated that a half molar fraction of the polymer chains in the
network remained unreacted, revealing further room for optimizing the
reaction condition. Since such tetra-PNIPAAm based motif can be readily
tailored to a variety of other physicochemical stimuli-responsive
analogues, our finding may give important insight into a platform for
‘smart’ tetra-gels with exceptional mechanical properties and
potentially highly controllable molecular cut-off capability.
Although previous studies have attempted to create
“electronics-free” insulin delivery systemsusing glucose oxidase and
sugar-binding lectins as a glucose-sensingmechanism, no successful
clinical translation has hitherto been made. These protein-based
materials are intolerant of long-term use and storage because of their
denaturing and/or cytotoxic properties. We provide a solution by
designing a protein-free and totally synthetic material-based approach.
Capitalizing on the sugar-responsive properties of boronic acid, we have
established a synthetic polymer gel-based insulin delivery device
confined within a single catheter, which exhibits an artificial
pancreas-like function in vivo. Subcutaneous implantation of the device
in healthy and diabetic mice establishes a closed-loop system composed
of “continuous glucose sensing” and “skin layer”-regulated
insulin release. As a result, glucose metabolism was controlled in
response to interstitial glucose fluctuation under both
insulin-deficient and insulin-resistant conditions with at least 3-week
durability. Our “smart gel” technology could offer a user-friendly
and remarkably economic (disposable) alternative to the current state of
the art, thereby facilitating availability of effective insulin
treatment not only to diabetic patients in developing countries but also
to those patients who otherwise may not be strongly motivated, such as
the elderly, infants, and patients in need of nursing care.
Identification of types of membrane injuries and cell death using whole
cell-based proton-sensitive field-effect transistor systems Imaizumi, Y.; Goda, T.; Matsumoto, A.; Miyahara, Y. Analyst2017, 142(18), 3451-3458. Abstract
An NH4Cl-superfused system for a cell-cultured pH-sensing transistor was
developed for detecting ion leakage across the plasma membranes of model
HepG(2) cells. The screening of chemical species by the method developed
and conventional membrane-leakage assays identified the types of
membrane injuries: structural membrane disruption and pore formation.
Apoptosis-mediated membrane disordering was detected by continuously
monitoring the ion-barrier breakdown of the membranes using the
transistor system for an extended period. Comparisons of the ISFET assay
with conventional cytotoxicity assays distinguished the cell death by
direct membrane injury from that by other organelle damage. Our
cell-based transistor system is fast and sensitive to ion leakage of the
plasma membrane due to the small hydrodynamic size of the proton and
ammonium ions as the indicators. The combination of the ion leakage
assay with the existing cytotoxicity assays is a new way of classifying
membrane injury and cell death induced by external chemical stimuli.
総説
‘Borono-lectin’ based engineering as a versatile platform for biomedical
applications Matsumoto, A.; Miyahara, Y. Sci. Technol. Adv. Mater.2017, 19(1), 18-30. Abstract
Boronic acids are well known for their ability to reversibly interact
with the diol groups, a common motif of biomolecules including sugars
and ribose. Due to their ability to interact with carbohydrates, they
can be regarded as synthetic mimics of lectins, termed ‘borono-lectins’.
The borono-lectins can be tailored to elicit a broad profile of binding
strength and specificity. This special property has been translated into
many creative biomedical applications in a way interactive with biology.
This review provides a brief overview of recent efforts of polymeric
materials-based engineering taking advantage of such virtue of
‘borono-lectins’ chemistry, related to the field of biomaterials and
drug delivery applications.
生体分子との相性が抜群な「ボロン酸工学」の発展を目指して (Aiming to develop ’boronic acid engineering’ that is highly compatible with biomolecules) 松元 亮. Nanosky2017, 3, 13.
2016
Potentiometric responses of ion-selective microelectrode with bovine
serum albumin adsorption Goda, T.; Yamada, E.; Katayama, Y.; Tabata, M.; Matsumoto, A.; Miyahara, Y. Biosens. Bioelectron.2016, 77, 208-214. Abstract
There is a growing demand for an in situ measurement of local pH and ion
concentrations in biological milieu to monitor ongoing process of
bioreaction and bioresponse in real time. An ion-selective
microelectrode can meet the requirements. However, the contact of the
electrode with biological fluids induces biofouling by protein
adsorption to result in a noise signal. Therefore, we investigated the
relationship between the amount of nonspecific protein adsorption and
the electrical signals in potentiometry by using ion-selective
microelectrodes, namely silver/silver chloride (Ag/AgCl),
iridium/iridium oxides (Ir/IrOx), and platinum/iridium oxides (Pt/IrOx).
The microelectrodes reduced a potential change following the adsorption
of bovine serum albumin (BSA) by comparison with the original metal
microelectrodes without oxide layers. Suppression in the noise signal
was attributed to the increased capacitance at the electrode/solution
interface due to the formation of granulated metal oxide layer rather
than a decrease in the amount of protein adsorbed. Ion sensitivity was
maintained for Ir/IrOx against proton, but it was not for Ag/AgCI
against chloride ion (Cl-), because of the interference of the
equilibrium reaction by adsorbed BSA molecules on the electrode surface
at <10(-2) M [Cl-] in the solution. The results open up the
application of the Ir/IrOx microelectrode for measuring local pH in
realistic dirty samples with a limited influence of electrode pollution
by protein adsorption. (C) 2015 Elsevier B.V. All rights reserved.
Real-time Monitoring and Detection of Primer Generation-Rolling Circle
Amplification of DNA Using an Ethidium Ion-selective Electrode Seichi, A.; Kozuka, N.; Kashima, Y.; Tabata, M.; Goda, T.; Matsumoto, A.; Iwasawa, N.; Citterio, D.; Miyahara, Y.; Suzuki, K. Anal. Sci.2016, 32(5), 505-510. Abstract
An electrochemical detection system for an isothermal DNA amplification
method using an ion-selective electrode (ISE) was developed as a
low-cost, simple and real-time monitoring system. The system is based on
potentiometry using an ethidium ion (Et+) selective electrode that
relies on monitoring DNA amplification by measuring potential changes in
the reaction solution containing ethidium bromide (EtBr) as an
intercalator to DNA. With progressing primer generation rolling circle
amplification (PG-RCA) under isothermal condition at 37 degrees C, EtBr
is bound to the newly formed DNA, resulting in a lowered free EtBr
concentration in the sample solution. In this case, the Et+ ISE
potential allows real-time monitoring of the PG-RCA reaction in the
range of 10 nM- 1 mu M initial target DNA.
Boronate-functionalized Polymer Gel-based Insulin Delivery System with
Improved Stability in Performance: A Comparative Structure-Function
Study Matsumoto, A.; Yuasa, M.; Matsumoto, H.; Sanjo, M.; Tabata, M.; Goda, T.; Hoshi, T.; Aoyagi, T.; Miyahara, Y. Chem. Lett.2016, 45(4), 460-462. Abstract
In an attempt to develop a totally synthetic, self-regulated insulin
delivery system to treat diabetes, N-substituted poly(acrylamide)
copolymer gels bearing boronate functionality have been chemically
optimized so as to undergo an abrupt and glucose dependent change in
hydration. This study highlights an importance of fine-tuning the mesh
size of the gel relative to that of insulin in order to achieve the
better controlled-release in a manner less sensitive to the temperature,
even with an apparently marginal change of hydration.
Miniaturized Ir/IrOx pH Sensor for Quantitative Diagnosis of Dental Caries Tabata, M.; Ratanaporncharoen, C.; Asano, A.; Kitasako, Y.; Ikeda, M.; Goda, T.; Matsumoto, A.; Tagami, J.; Miyahara, Y. Procedia Eng.2016, 168, 598-601. Abstract
Diagnosis of dental caries is one of the most basic skills for oral healthcare professionals; however, the detection methods are based on visually diagnosis, such as inspection, palpation, and X-ray imaging. Therefore, quantitative and objective diagnostic technique is needed [1]. The aim of this study is fabrication and evaluation of Iridium/Iridium Oxide (Ir/IrOx) pH sensor for quantitative diagnosis of dental caries. The potentiometric response to pH showed -57.4mV/pH in evaluated pH range from 4 to 8, which demonstrated that our electrode possesses the excellent proton sensitivity (Nernst slope; -59.2mV/pH). Based on the evaluation results of dental caries, we confirmed the possibility for quantitative diagnosis of dental caries using Ir/IrOx electrode based on the pH as an index.
Label-free and Electrochemical Detection of Nucleic Acids Based on Isothermal Amplification in Combination with Solid-state pH Sensor Tabata, M.; Katayama, Y.; Mannan, F.; Seichi, A.; Suzuki, K.; Goda, T.; Matsumoto, A.; Miyahara, Y. Procedia Eng.2016, 168, 419-422. Abstract
Label-free quantification methods for nucleic acids are attracting attention, since they provide potential tools in clinical applications such as disease diagnosis or prognosis observation. In this research, we developed a simpler and cost-effective electrical monitoring device of nucleic acid amplification, combining an isothermal amplification method and an Iridium/Iridium oxide (Ir/IrOx) electrode without labeling. The fabricated Ir/IrOx electrode showed ideal Nernstian response under the various pH buffer solutions, and its potential response was less affected even in the presence of charged proteins. Moreover, we successfully real-time monitored primer generation-rolling circle amplification (PG-RCA) at the 0, 10, 100, 1000 pM of target DNA by detection of released proton during amplification reaction at the constant reaction temperature. This label-free and portable device might be received considerable attention as a useful platform for a point-of-care testing in clinical use.
Oleyl group-functionalized insulating gate transistors for measuring
extracellular pH of floating cells Imaizumi, Y.; Goda, T.; Toya, Y.; Matsumoto, A.; Miyahara, Y. Sci. Technol. Adv. Mater.2016, 17(1), 337-345. Abstract
The extracellular ionic microenvironment has a close relationship to
biological activities such as by cellular respiration, cancer
development, and immune response. A system composed of ion-sensitive
field-effect transistors (ISFET), cells, and program-controlled fluidics
has enabled the acquisition of real-time information about the integrity
of the cell membrane via pH measurement. Here we aimed to extend this
system toward floating cells such as T lymphocytes for investigating
complement activation and pharmacokinetics through alternations in the
plasma membrane integrity. We functionalized the surface of tantalum
oxide gate insulator of ISFET with oleyl-tethered phosphonic acid for
interacting with the plasma membranes of floating cells without
affecting the cell signaling. The surface modification was characterized
by X-ray photoelectron spectroscopy and water contact angle
measurements. The Nernst response of -37.8 mV/pH was obtained for the
surface-modified ISFET at 37 degrees C. The oleyl group-functionalized
gate insulator successfully captured Jurkat T cells in a fluidic
condition without acute cytotoxicity. The system was able to record the
time course of pH changes at the cells/ISFET interface during the
process of instant addition and withdrawal of ammonium chloride.
Further, the plasma membrane injury of floating cells after exposure by
detergent Triton (TM) X-100 was successfully determined using the
modified ISFET with enhanced sensitivity as compared with conventional
hemolysis assays.
[GRAPHICS]
著書
Field-Effect Transistors for Detection of Biomolecular Recognition Tabata, M.; Goda, T.; Matsumoto, A.; Miyahara, Y. Intelligent Nanosystems for Energy, Information and Biological Technologies2016, 13-25 (Springer). Abstract
Electrical biosensors have attracted increasing attention in such fields as point-of-care testing, drug discovery, and healthcare products. In order for next-generation biosensor platforms to become more useful in our daily lives, it will be necessary to significantly improve their sensitivity, specificity, and parallelism. A precisely designed thin layer in molecular dimension on a solid substrate is essential for biosensing. The surfaces of biosensors are designed to capture target bioanalytes. In addition, the solid/liquid interface plays an important role in realizing additional functionalities such as target manipulation, signal stabilization, and switching. A functional interface combined with a field-effect device would enable on-demand label-free biosensing in a portable format. In this chapter, we provide an overview of biomolecular recognition in the context of electrochemical sensing and biosensing. Also, we review recent progress and trends in biosensing, including our own research.
2015
Poly(3,4-ethylenedioxythiophene) Bearing Phosphorylcholine Groups for
Metal-Free, Antibody-Free, and Low-Impedance Biosensors Specific for
C-Reactive Protein Goda, T.; Toya, M.; Matsumoto, A.; Miyahara, Y. ACS Appl. Mater. Interfaces2015, 7(49), 27440-27448. Abstract
Conducting polymers possessing biorecognition elements are essential for
developing electrical biosensors sensitive and specific to clinically
relevant biomolecules. We developed a new 3,4-ethylenedioxythiophene
(EDOT) derivative bearing a zwitterionic phosphorylcholine group via a
facile synthesis through the Michael-type addition thiol-ene “click”
reaction for the detection of an acute-phase biomarker human C-reactive
protein (CRP). The phosphorylcholine group, a major headgroup in
phospholipid, which is the main constituent of plasma membrane, was also
expected to resist nonspecific adsorption of other proteins at the
electrode/solution interface. The biomimetic EDOT derivative was
randomly copolymerized with EDOT, via an electropolyrnerization
technique with a dopant sodium perchlorate, onto a glassy carbon
electrode to make the synthesized polymer film both conductive and
target-responsive. The conducting copolymer films were characterized by
cyclic voltammetry, scanning electron microscopy, attenuated total
reflection Fourier transform infrared spectroscopy, X-ray photoelectron
spectroscopy, and electrochemical impedance spectroscopy. The specific
interaction of CRP with phosphorylcholine in a calcium-containing buffer
solution was determined by differential pulse voltammetry, which
measures the altered redox reaction between the indicators
ferricyanide/ferrocyanide as a result of the binding event. The
conducting polymer-based protein sensor achieved a limit of detection of
37 nM with a dynamic range of 10-160 nM, covering the dynamically
changing CRP levels in circulation during the acute phase. The results
will enable the development of metal-free, antibody-free, and
low-impedance electrochemical biosensors for the screening of
nonspecific biomarkers of inflammation and infection.
Dual aptamer-immobilized surfaces for improved affinity through multiple
target binding in potentiometric thrombin biosensing Goda, T.; Higashi, D.; Matsumoto, A.; Hoshi, T.; Sawaguchi, T.; Miyahara, Y. Biosens. Bioelectron.2015, 73, 174-180. Abstract
We developed a label-free and reagent-less potentiometric biosensor with
improved affinity for thrombin. Two different oligomeric DNA aptamers
that can recognize different epitopes in thrombin were introduced in
parallel or serial manners on the sensing surface to capture the target
via multiple contacts as found in many biological systems. The spacer
and linker in the aptamer probes were optimized for exerting the best
performance in molecular recognition. To gain the specificity of the
sensor to the target, an antifouling molecule,
sulfobeaine-3-undecanethiol (SB), was introduced on the sensor to form a
self-assembled monolayer (SAM). Surface characterization revealed that
the aptamer probe density was comparable to the distance of the two
epitopes in thrombin, while the backfilling SB SAM was tightly aligned
on the surface to resist nonspecific adsorption. The apparent binding
parameters were obtained by thrombin sensing in potentiometry using the
1:1 Langmuir adsorption model, showing the improved dissociation
constants (K-d) with the limit of detection of 5.5 nM on the dual
aptamer-immobilized surfaces compared with single aptamer-immobilized
ones. A fine control of spacer and linker length in the aptamer ligand
was essential to realize the multivalent binding of thrombin on the
sensor surface. The findings reported herein are effective for improving
the sensitivity of potentiometric biosensor in an affordable way towards
detection of tiny amount of biomolecules. (C) 2015 Elsevier B.V. All
rights reserved.
Boronate Based Metal-Free Platform for Diphosphate-Specific Molecular
Recognitions Sanjoh, M.; Iizuka, D.; Matsumoto, A.; Miyahara, Y. Org. Lett.2015, 17(3), 588-591. Abstract
A reversible boronate-diol interaction provides a versatile synthetic
platform for molecular recognitions whose binding specificity can be
molecularly tailored. We found that boronate derivatives with relatively
strong acidity generally undergo a diphosphate-specific recognition
among other phosphates under weakly acidic pH conditions, a feature
relevant to DNA sequencing. B-11 and P-31 NMR studies identified
“tetrahedral boronate and divalent diphosphate” as a pair
responsible for forming a 1:1 stoichiometric complex, which manifests as
a unique pH-dependent stability.
2014
Chemical Optimization for Simultaneous Voltammetric Detection of
Molybdenum and Silver Nanoparticles in Aqueous Buffer Solutions Goda, T.; Oohashi, M.; Matsumoto, A.; Hoshi, T.; Sawaguchi, T.; Pumera, M.; Miyahara, Y. ChemElectroChem2014, 1(12), 2110-2115. Abstract
Simultaneous acquisition of redox signals from different types of metal
nanoparticles (NPs) in a multiplexing system requires a good separation
in redox potential from each component for successful identification.
The appearance of a single distinct peak for each NP type is also
preferred. Here, we report variations in the electrochemical nature of
molybdenum (Mo) and silver (Ag) NPs cast on a glassy carbon electrode
that are sensitive to various conditions of the measurement solution,
such as buffering capacity and electrolyte concentration. A series of
experiments allowed us to find optimal conditions, where Mo NPs showed a
single oxidation peak with good separation of the redox potential from
that of Ag NPs (Delta E approximate to 0.25 V), by using
differential-pulse voltammetry (DPV). In the simultaneous monitoring of
Mo and Ag NPs under the optimal conditions, the peak currents in DPV
were quantitative for the amount of Mo/Ag NPs ranging from 7.8/20 to
500/20 ngng(-1) and from 500/20 to 500/0.31 ngng(-1).
Fabrication of Self-assembled Monolayer/AgCl Mixed Surface and It’s Electrochemical Properties Tabata, M.; Nogami, K.; Goda, T.; Matsumoto, A.; Miyahara, Y. IEEJ Trans. Sens. Micromachines2014, 134(10), 315-319. Abstract
There is increasing interest on solid-state biosensors due to potential advantages such as small size, low-cost, high density integration for point of care testing and next-generation drug discovery. In many cases, a gold electrode is used as a sensing surface on which specific biomolecule recognition events take place. However, gold is not always the best material for potentiometric measurement since the surface of gold electrode is polarized in aqueous solution, and there is room for improvement in stability of interface potential at the gold electrode surface. In this paper, we fabricated and characterized the mixed surface of self-assembled monolayer of alkanethiol and silver chloride to realize both stable interface potential and immobilization of biomolecules.
Chemo-Electrical Signal Transduction by Using Stimuli-Responsive Polymer Gate-Modified Field Effect Transistor Matsumoto, A.; Tsurui, Y.; Matsumoto, H.; Maeda, Y.; Hoshi, T.; Sawaguchi, T.; Miyahara, Y. Chemosensors2014, 2(2), 97-107. Abstract
A glucose-responsive polymer brush was designed on a gold electrode and exploited as an extended gate for a field effect transistor (FET) based biosensor. A permittivity change at the gate interface due to the change in hydration upon specific binding with glucose was detectable. The rate of response was markedly enhanced compared to the previously studied cross-linked or gel-coupled electrode, owing to its kinetics involving no process of the polymer network diffusion. This finding may offer a new strategy of the FET-based biosensors effective not only for large molecules but also for electrically neutral molecules such as glucose with improved kinetics.
Current Development Status and Perspectives of Self-Regulated Insulin Delivery Systems: A Review Matsumoto, A.; Miyahara, Y. Electr. Commun. Jpn.2014, 97(12), 57-61. Abstract
Diabetes is not an infectious disease but its increasingly rapid and
worldwide spread has been recognized as pandemic. Despite the necessity
for continuous and accurate glycemic control in the management of
insulin-dependent diabetes mellitus, the current palliative treatment
relies almost solely on patient self-injection of insulin, which not
only impinges on the QOL of patients but also fails to precisely control
the dose of insulin, where an overdose must be strictly avoided since it
can otherwise cause serious hypoglycemia. The development of
self-regulated insulin delivery systems is a long-standing challenge for
materials science, for which the exploitation of glucose oxidase and
sugar-binding lectin are two prevalent strategies to achieve the
function of glucose sensitivity. These protein-based components,
however, are inappropriate for long-term use and storage due to their
denaturing and cytotoxic natures, and they are hardly suitable for any
implantable applications. Thus, they have not yet been put in clinical
use to date. This review intends to provide an overview of the current
efforts to develop a thoroughly synthetic alternative making use of a
phenylboronic acid-derived polyacrylamide gel.
総説
Phenylboronic Acids-based Diagnostic and Therapeutic Applications Sanjoh, M.; Miyahara, Y.; Kataoka, K.; Matsumoto, A. Anal. Sci.2014, 30(1), 111-117. Abstract
Phenylboronic acid (PBA) derivatives are known to form reversible
complexes with polyols, including sugars. This unique chemistry has
provided many useful molecular bases for analytical and therapeutic
applications. This mini-review highlights some new aspects of related
research efforts with a special focus on the interaction with sialic
acid as a new class of molecular targets and other PBA-based strategies
for drug delivery applications.
New directions in the design of phenylboronate-functionalized polymers
for diagnostic and therapeutic applications Matsumoto, A.; Kataoka, K.; Miyahara, Y. Polym. J.2014, 46(8), 483-491. Abstract
Phenylboronic acid (PBA) derivatives, which are often termed
boronolectins,’ are regarded as a synthetic mimic of lectins because of
their ability to interact with various carbohydrates. This unique
chemistry has already borne fruit as the molecular bases for glucose
sensors and some bio-separation applications. This focus review
highlights some of the emerging PBA-based research directions toward
more versatile diagnostic and therapeutic targets, which the authors are
currently pursuing. The topics reviewed include PBA-mediated targeting
to sialic acid (SA) as a methodology relevant to tumor diagnosis and
treatment. Other drug delivery systems, including those for siRNA and
insulin, in which PBA has a unique role in physicochemical signal
transduction, will also be summarized.
著書
スマートゲルを利用した完全合成型の“人工膵臓 (Development of a Totally Synthetic ’Artificial Pancreas’) 松元 亮; 宮原 裕二. スマート・ヒューマンセンシング ~健康ビッグデータ時代のためのセンサ・情報・エネルギー技術~ (Human Sensing for Smart Life Care - Sensor, Information & Energy Technologies on Health Conscious Society with Big Data) 2014, Chapter 3.4, 233-240 (CMC Publishing Co., Ltd).
ボロン酸ゲルによるインスリンデリバリーシステム (Phenylboronate Gel Based Insulin Delivery Systems) 松元 亮; 片岡一則; 宮原 裕二. ゲルテクノロジーハンドブックグ ~機能設計・評価・シミュレーションから製造プロセス・製品化まで~ (Science and Technology Handbook of Gels - From functional design, evaluation, and simulation to manufacturing process and commercialization) 2014, Chapter 3.1, (NTS Inc.).
Label-Free Potentiometry for Detecting DNA Hybridization Using Peptide
Nucleic Acid and DNA Probes Goda, T.; Singi, A. B.; Maeda, Y.; Matsumoto, A.; Torimura, M.; Aoki, H.; Miyahara, Y. Sensors2013, 13(2), 2267-2278. Abstract
Peptide nucleic acid (PNA) has outstanding affinity over DNA for
complementary nucleic acid sequences by forming a PNA-DNA heterodimer
upon hybridization via Watson-Crick base-pairing. To verify whether PNA
probes on an electrode surface enhance sensitivity for potentiometric
DNA detection or not, we conducted a comparative study on the
hybridization of PNA and DNA probes on the surface of a 10-channel gold
electrodes microarray. Changes in the charge density as a result of
hybridization at the solution/electrode interface on the self-assembled
monolayer (SAM)-formed microelectrodes were directly transformed into
potentiometric signals using a high input impedance electrometer. The
charge readout allows label-free, reagent-less, and multi-parallel
detection of target oligonucleotides without any optical assistance. The
differences in the probe lengths between 15- to 22-mer dramatically
influenced on the sensitivity of the PNA and DNA sensors. Molecular type
of the capturing probe did not affect the degree of potential shift.
Theoretical model for charged rod-like duplex using the Gouy-Chapman
equation indicates the dominant effect of electrostatic attractive
forces between anionic DNA and underlying electrode at the
electrolyte/electrode interface in the potentiometry.
Phenylboronic Acid-Installed Polymeric Micelles for Targeting Sialylated
Epitopes in Solid Tumors Deshayes, S.; Cabral, H.; Ishii, T.; Miura, Y.; Kobayashi, S.; Yamashita, T.; Matsumoto, A.; Miyahara, Y.; Nishiyama, N.; Kataoka, K. J. Am. Chem. Soc.2013, 135(41), 15501-15507. Abstract
Ligand-mediated targeting of nanocarriers to tumors is an attractive
strategy for increasing the efficiency of chemotherapies. Sialylated
glycans represent a propitious target as they are broadly overexpressed
in tumor cells. Because phenylboronic acid (PBA) can selectively
recognize sialic acid (SA), herein, we developed PBA-installed micellar
nanocarriers incorporating the parent complex of the anticancer drug
oxaliplatin, for targeting sialylated epitopes overexpressed on cancer
cells. Following PBA-installation, the micelles showed high affinity for
SA, as confirmed by fluorescence spectroscopy even at intratumoral pH
conditions, i.e., pH 6.5, improving their cellular recognition and
uptake and enhancing their in vitro cytotoxicity against B16F10 murine
melanoma cells. In vivo, PBA-installed micelles effectively reduced the
growth rate of both orthotopic and lung metastasis models of melanoma,
suggesting the potential of PBA-installed nanocarriers for enhanced
tumor targeting
Biotransistor with functional nanointerface containing biomolecules Tabata, M.; Goda, T.; Matsumoto, A.; Miyahara, Y. IEEJ Trans. Sens. Micromachines2013, 133(11), B314-B319. Abstract
The convergence of nano-/bio- technology with biomedicine has occurred tremendously over the last few decades. In particular, next-generation biosensors offer great potential to treat serious medical problems in the fields of diagnostics, therapy, and drug delivery. Advantageously, an electrical biosensor platform composed of target-capturing element and semiconductor device as a signal transducer is compatible with a high-throughput analysis via miniaturization and integration into a small chip for decentralized bioanalytical applications. So far, we have successfully achieved potentiometric biosensing based mostly on a direct readout of innately charged biomolecules using field effect transistor (FET). Highly specific molecular recognition is available by constructing engineered biointerface on the sensor. Furthermore, the potentiometric technique provides the ability to perform label-free and real-time detection for various biomolecules. These features would help to promote personalized medicine for individual patients in the future. Here we describe fundamental aspects of electrical biosensing and review recent developments of the FET-based biotransistors.
Simple and robust strategy for potentiometric detection of glucose using
fluorinated phenylboronic acid self-assembled monolayer Matsumoto, A.; Matsumoto, H.; Maeda, Y.; Miyahara, Y. Biochim. Biophys. Acta-Gen. Subj.2013, 1830(9, SI), 4359-4364. Abstract
Background: Field effect transistor (PET) based signal-transduction
(Bio-FET) is an emerging technique for label-free and real-time basis
biosensors for a wide range of targets. Glucose has constantly been of
interest due to its clinical relevance. Use of glucose oxidase (GOD) and
a lectin protein Concanavalin A are two common strategies to generate
glucose-dependent electrochemical events. However, these protein-based
materials are intolerant of long-term usage and storage due to their
inevitable denaturing.
Methods: A phenylboronic acid (PEA) modified self-assembled monolayer
(SAM) on a gold electrode with an optimized disassociation constant of
PBA, that is, 3-fluoro-4-carbamoyl-PBA possessing its pKa of 7.1, was
prepared and utilized as an extended gate electrode for Bio-FET.
Results: The prepared electrode showed a glucose-dependent change in the
surface potential under physiological conditions, thus providing a
remarkably simple rationale for the glyco-sensitive Bio-FET.
Importantly, the PBA modified electrode showed tolerance to relatively
severe heat and drying treatments; conditions under which protein based
materials would surely be denatured.
Conclusions: A PEA modified SAM with optimized disassociation constant
(pKa) can exhibit a glucose-dependent change in the surface potential
under physiological conditions, providing a remarkably simple but robust
method for the glyco-sensing.
General significance: This protein-free, totally synthetic glyco-sensing
strategy may offer cheap, robust and easily accessible platform that may
be useful in developing countries. This article is part of a Special
Issue entitled Organic Bioelectronics-Novel Applications in Biomedicine.
(C) 2013 Elsevier B.V. All rights reserved.
Current and emerging challenges of field effect transistor based
bio-sensing Matsumoto, A.; Miyahara, Y. Nanoscale2013, 5(22), 10702-10718. Abstract
Field-effect-transistor (FET) based electrical signal transduction is an
increasingly prevalent strategy for bio-sensing. This technique, often
termed ’Bio-FETs’, provides an essentially label-free and real-time
based bio-sensing platform effective for a variety of targets. This
review highlights recent progress and challenges in the field. A special
focus is on the comprehension of emerging nanotechnology-based
approaches to facilitate signal-transduction and amplification. Some new
targets of Bio-FETs and the future perspectives are also discussed.
機能性ナノ界面を有するバイオトランジスタ (Biotransistor with Functional Nanointerface Containing Biomolecules) 田畑 美幸; 合田 達郎; 松元 亮; 宮原 裕二. 電気学会論文誌E (センサ・マイクロマシン部門誌) (IEEJ Transactions on Sensors and Micromachines) 2013, 133(11), 314-319. Abstract
The convergence of nano-/bio- technology with biomedicine has occurred tremendously over the last few decades. In particular, next-generation biosensors offer great potential to treat serious medical problems in the fields of diagnostics, therapy, and drug delivery. Advantageously, an electrical biosensor platform composed of target-capturing element and semiconductor device as a signal transducer is compatible with a high-throughput analysis via miniaturization and integration into a small chip for decentralized bioanalytical applications. So far, we have successfully achieved potentiometric biosensing based mostly on a direct readout of innately charged biomolecules using field effect transistor (FET). Highly specific molecular recognition is available by constructing engineered biointerface on the sensor. Furthermore, the potentiometric technique provides the ability to perform label-free and real-time detection for various biomolecules. These features would help to promote personalized medicine for individual patients in the future. Here we describe fundamental aspects of electrical biosensing and review recent developments of the FET-based biotransistors.
2012
Preparation of α-mannoside hydrogel and electrical detection of
saccharide-protein interactions using the smart gel-modified gate field
effect transistor Maeda, Y.; Matsumoto, A.; Miura, Y.; Miyahara, Y. Nanoscale Res. Lett.2012, 7, 1-8. Abstract
The purpose of this study was to detect saccharide-protein interaction
capitalizing on the gel-modified field effect transistor [FET]. A
lectin-sensitive polymer gel that undergoes volume changes in response
to the formation of molecular complex between ‘pendant’ carbohydrate and
a ‘target’ lectin concanavalin A [Con A] was synthesized. It was
revealed that direction and magnitude of the gel response (swelling or
deswelling) could be readily designed depending on composition and
network density of the gel. The Con A-sensitive polymer gel has shown
the ability to transduce the detection of saccharide-protein
interactions into electrical signals for FET.
A label-free electrical detection of exosomal microRNAs using
microelectrode array Goda, T.; Masuno, K.; Nishida, J.; Kosaka, N.; Ochiya, T.; Matsumoto, A.; Miyahara, Y. Chem. Commun.2012, 48(98), 11942-11944. Abstract/Cover
We report a method for detecting microRNAs encapsulated in exosomes
using a microelectrode array in semiconductor-based potentiometry after
RT-PCR. The inherent miniaturization of the electrical biosensor meets
requirements for massively parallel analysis of circulating microRNA as
a noninvasive biomarker.
A Phenylboronate-Functionalized Polyion Complex Micelle for
ATP-Triggered Release of siRNA Naito, M.; Ishii, T.; Matsumoto, A.; Miyata, K.; Miyahara, Y.; Kataoka, K. Angew. Chem.-Int. Edit.2012, 51(43), 10751-10755. Abstract/Cover
PIC-ing a winner: siRNA encapsulated by a phenylboronate-functionalized polyion complex (PIC) micelle shows binding between the phenylboronate and the 3′ ribose of the siRNA (see scheme), stabilizing the complex under conditions equivalent to the extracellular environment. This complex is disrupted in response to addition of ATP, at a concentration comparable to that inside cells.
A Synthetic Approach Toward a Self-Regulated Insulin Delivery System Matsumoto, A.; Ishii, T.; Nishida, J.; Matsumoto, H.; Kataoka, K.; Miyahara, Y. Angew. Chem.-Int. Edit.2012, 51(9), 2124-2128. Abstract/Cover
Protein-free: A hydrogel containing phenylboronate was optimized so as to undergo rapid glucose-dependent changes in the state of hydration under physiological aqueous conditions. A localized dehydration of the gel surface to form a “skin layer” enabled control of the release of insulin from the gel. This dehydration is induced by fluctuations in the glucose concentration in the range between normo- and hyperglycemia.
総説
自律型インスリン投与デバイスの開発状況と将来展望 (レビュー) (Current Development Status and Perspective of Self-Regulated Insulin Delivery Systems: A Review) 松元 亮; 宮原 裕二. 電気学会論文誌E (センサ・マイクロマシン部門誌) (IEEJ Transactions on Sensors and Micromachines) 2012, 132(12), 455-458. Abstract
Diabetes is not an infectious disease but its increasingly rapid and worldwide prevalence has been recognized as "pandemic". Despite the necessity for continuous and accurate glycemic control in the management of insulin dependent diabetes mellitus, the current palliative treatment relies almost solely on the patient-self injection of insulin, which not only impinges on quality of life of the patients but also fails to precisely control dose of insulin where the overdose must be strictly avoided otherwise causing serious hypoglycemia. Development of self-regulated insulin delivery systems is a long-standing challenge of materials science, for which exploitations of glucose oxidase and sugar-binding lectin are two prevalent strategies to install the function of glucose-sensitivity. These protein-based components, however, intolerant of long-term use and storage with their denaturing and cytotoxic natures, are hardly suitable for any implantable applications thus have not yet been in clinical usage to date. This review intends to provide an overview of the current efforts to develop a thoroughly synthetic alternative making use of a phenylboronic acid derivatized polyacrylamide gel.
著書
Intelligent Surfaces for Field-Effect Transistor-Based Nanobiosensing Matsumoto, A.; Miyahara, Y.; Kataoka, K. Intelligent Surfaces in Biotechnology: Scientific and Engineering Concepts, Enabling Technologies, and Translation to Bio‐Oriented Applications2012, Chapter 4, 123-140 (John Wiley & Sons, Ltd). Abstract
Summary:
Introduction
FET-Based Biosensors
Intelligent Surfaces for Signal Transduction and Amplifi cation of bio-FETs
New Targets of bio-FETs
Future Perspective
References
2011
Toward a Continuous Intravascular Glucose Monitoring System Beier, B.; Musick, K.; Matsumoto, A.; Panitch, A.; Nauman, E.; Irazoqui, P. Sensors2011, 11(1), 409-424. Abstract
Proof-of-concept studies that display the potential of using a
glucose-sensitive hydrogel as a continuous glucose sensor are presented.
The swelling ratio, porosity, and diffusivity of the hydrogel increased
with glucose concentration. In glucose solutions of 50, 100, 200, and
300 mg/dL, the hydrogel swelling ratios were 4.9, 12.3, 15.9, and 21.7,
respectively, and the swelling was reversible. The impedance across the
hydrogel depended solely on the thickness and had an average increase of
47 Omega/mm. The hydrogels exposed to a hyperglycemic solution were more
porous than the hydrogels exposed to a normal glycemic solution. The
diffusivity of 390 Da MW fluorescein isothiocyanate in hydrogels exposed
to normal and hyperglycemic solutions was examined using fluorescence
recovery after photobleaching and was found to be 9.3 x 10(-14) and 41.4
x 10(-14) m(2)/s, respectively, compared to 6.2 x 10(-10) m(2)/s in
glucose solution. There was no significant difference between the
permeability of hydrogels in normal and hyperglycemic glucose solutions
with averages being 5.26 x 10(-17) m(2) and 5.80 x 10(-17) m(2),
respectively, which resembles 2-4% agarose gels. A prototype design is
presented for continuous intravascular glucose monitoring by attaching a
glucose sensor to an FDA-approved stent.
総説
バイオセンサの現状と今後の展望 (Trend and Perspective of Biosensors) 松元 亮; 宮原 裕二. 応用物理 (Applied Physics) 2011, 80(3), 205-210. Abstract
A totally synthetic glucose responsive gel operating in physiological
aqueous conditions Matsumoto, A.; Yamamoto, K.; Yoshida, R.; Kataoka, K.; Aoyagi, T.; Miyahara, Y. Chem. Commun.2010, 46(13), 2203-2205. Abstract/Cover
Here described is a phenylboronic acid (PBA) based glucose-responsive
hydrogel operating under physiological pH and temperature, a material
potentially applicable to a totally synthetic smart insulin delivery
system to treat diabetes.
Hydrogel-based field effect transistor for lectin detection Maeda, Y.; Matsumoto, A.; Miura, Y.; Miyahara, Y. Eur. Cells Mater.2010, 20(SUPPL.3), 167.
Bio-transistor for Label Free Living Cell Diagnosis Matsumoto, A.; Sato, N.; Yoshida, R.; Kataoka, K.; Miyahara, Y. Eur. Cells Mater.2010, 20(SUPPL.3), 173.
Development of cell/transistor interface for real-time and noninvasive monitoring of potassium ion release based on apoptosis using biologically-coupled field effect transistor Murakami, T.; Sakata, T.; Matsumoto, A.; Takai, M.; Ishihara, K.; Miyahara, Y. Trans. Mat. Res. Soc. Jpn2010, 35(2), 255-258. Abstract
We report the real-time and noninvasive detection of K+ release through cell membrane using a biologically-coupled field effect transistor (bio-FET). To achieve this purpose, the cell/transistor interface, which can selectively detect K+ release through the ion-channel, was developed. The K+ release through the ion-channel caused by apoptosis (programmed cell death) could be electrically detected using the bio-FET with crown ether monolayer. Thus we have demonstrated the ability to analyze selectively the ion channel behavior using the bio-FET modified with the functional monolayer.
Self-assembled molecular gate field effect transistor for label free sialic acid detection at cell membrane Matsumoto, A.; Sato, N.; Cabral, H.; Kataoka, K.; Miyahara, Y. Procedia Eng.2010, 5, 926-929. Abstract
This work describes a label free, potentiometric method to detect cell surface sialic acid (SA) using phenylboronic acid (PBA) compound integrated into the form of self-assembled monolayer (SAM) on a field effect transistor (FET) extended gold gate electrode. Due to predominant binding between undisassociated PBA and SA at pH 7.4, we found that carboxyl anions of SA were exclusively detectable among other glycan chain constituent monosaccharides, b as the change in threshold voltage (VT) of the PBA-modified FET. The technique was applied to analyses of altered SA expressions on rabbit erythrocyte as a models for diabetes. The comparative analyses revealed that the disease could be feasibly diagnosed simply by placing the cell suspensions onto the device without any labelling and enzymatic procedures.
Assessment of Tumor Metastasis by the Direct Determination of
Cell-Membrane Sialic Acid Expression Matsumoto, A.; Cabral, H.; Sato, N.; Kataoka, K.; Miyahara, Y. Angew. Chem.-Int. Edit.2010, 49(32), 5494-5497. AbstractPress release
In a world without labels…︁ A self-assembled phenylboronic acid monolayer on the surface
of a gold electrode enabled the potentiometric detection of cell-membrane sialic acid (SA; see diagram)
and differentiation of healthy pneumocytes from metastatic melanoma cells on the basis of altered SA
expression. This approach to the diagnosis of tumoral malignancy or the degree of metastasis holds
promise for label-free, noninvasive, real-time cytology.
バイオトランジスタによる生体分子認識の検出 (Detection of Biomolecule recognition using Biotransistors) 宮原 裕二; 坂田 利弥; 松元 亮; 片岡 知歩. バイオチップ実用化ハンドブック (Handbook of Biochip Technology) 2010, Chapter 4, 518-528 (NTS Inc.).
薬物放出ゲル (Drug Release Gel) 松元 亮; 宮原 裕二. 食品・化粧品・医療分野へのゲルの利用 (Utilization of Gels in Food,Cosmetics and Medicine) 2010, Chapter 6, 240-245 (CMC Publishing Co., Ltd).
2009
Electrical visualization of chemo-mechanical signal transduction using a
smart gel-modified gate field effect transistor Matsumoto, A.; Endo, T.; Yoshida, R.; Miyahara, Y. Chem. Commun.2009, 5609-5611. Abstract
A field effect transistor (FET) whose gate surface has been modified
with a stimuli-responsive “smart” polymer gel can visualize the
kinetics of the chemo-mechanical signal transduction as a mode of its
altered electrical characteristics without any labels.
Noninvasive Sialic Acid Detection at Cell Membrane by Using
Phenylboronic Acid Modified Self-Assembled Monolayer Gold Electrode Matsumoto, A.; Sato, N.; Kataoka, K.; Miyahara, Y. J. Am. Chem. Soc.2009, 131(34), 12022-12023. Abstract
Alternations of sialic acid (SA) content on cell surface glycan chains
have been implicated in numerous normal and pathological processes
including developments, differentiations, and tumor metastasis.
Overexpressions of SA have been implicated in the malignant and
metastatic phenotypes for many different types of cancers, while
decreased SA expression has also been identified in erythrocytes of
diabetic mellitus. Techniques to conveniently monitor cell surface SA
would therefore have great relevance to cytology. Preexisting
methodologies to quantify SA, however, involve multiple enzymatic,
dye-labeling, and lethal procedures, which are costly and
time-consuming. Here we developed a potentiometric SA detection using a
phenytboronic acid (PBA) compound integrated into the form of a
self-assembled monolayer (SAM) onto a field effect transistor (FET)
extended gold gate electrode. Due to selective binding between
undisassociated PBA and SA at pH 7.4 among other glycan chain
constituent monosaccharides, we found that carboxyl anions of SA were
exclusively detectable as the change in threshold voltage (V-T) of the
PBA-modified FET. The technique was applied to analyses of altered SA
expressions on rabbit erythrocyte as a model for diabetes. Comparative
SA expression analyses for each healthy and diseased model revealed that
the disease could be feasibly diagnosed simply by placing the
known-count cell suspensions onto the device without any labeling and
enzymatic procedures. Such a technique may also provide a quantitative
adjunct to histological evaluation of tumor malignancy and metastatic
potential during intra- and postoperative diagnoses. Also
advantageously, a technique herein described is all within a CMOS
(Complementary Metal Oxide Semiconductor) compatible format thus
promising for highly efficient and tow cost manufacturing with readiness
of downsizing and integration by virtue of advanced semiconductor
processing technologies.
Chemical-to-Electrical-Signal Transduction Synchronized with Smart Gel
Volume Phase Transition Matsumoto, A.; Sato, N.; Sakata, T.; Yoshida, R.; Kataoka, K.; Miyahara, Y. Adv. Mater.2009, 21(43), 4372-4378. Abstract
A stimulus-responsive polymer gel designed on a field-effect transistor
gate undergoes a reversible volume phase transition in response to a
specific biomolecule. An abrupt permittivity change at the gel/gate
interface during the transition gives rise to a chemical to electrical
signal conversion; the signal is thus detectable via a transistor
without the limit of the Debye length.
Glucose-sensitive field effect transistor using totally synthetic
compounds Matsumoto, A.; Sato, N.; Sakata, T.; Kataoka, K.; Miyahara, Y. J. Solid State Electrochem.2009, 13(1), 165-170. Abstract
A field effect transistor (FET)-based glucose sensor was fabricated. As
a totally synthetic and thus stable glucose-sensing moiety,
3-acrylamidophenylboronic acid was chemically introduced onto the FET
gate surface in the form of a thin copolymer gel layer. Excellent
transistor characteristics were confirmed even after the surface
modification, ensuring validity of the modification procedure herein
developed. Glucose-induced changes in the FET’s electric characteristics
were obtained in quantitative as well as reversible manners. It was also
demonstrated that the prepared FET is able to continuously perceive the
change in the glucose concentration in the milieu. The detected signals
were attributed to the faction change of the gate-introduced phenyborate
anions, also presumably involving other parameter changes such as
permittivity and conductivity. The use of the fabricated FET could
further be extended to the construction of stable, readily
minutualizable, and label-free carbohydrate molecule-sensing systems.
Label free carbohydrate detection by using phenylboronic acid
gate-modified field effect transistor Matsumoto, A.; Sato, N.; Miyahara, Y. Curr. Appl. Phys.2009, 9(4, 1), E214-E217. Abstract
This paper describes a field effect transistor (FET) based sugar
molecule sensor, using a totally synthetic and chemically stable
sugar-detecting moiety phenylboronic acid (PBA). PBA was introduced to
the FET sensing surfaces in two different ways. One is in the form of a
thin copolymer gel layer directly attached to the FET gate insulator,
the other method utilizes self-assembled monolayer (SAM) formed on an
extended Au gate surface, a functional group of which was reacted with
PBA. Reversible and prompt changes in the FET’s electric characteristics
were demonstrated in response to the change in glucose and sialic acid
(Neu5Ac) concentrations depending on the pH of the milieu. The developed
FET detection scheme could be extended to the construction of stable,
readily miniaturizable, and label-free carbohydrate molecule sensing
systems due to the ability of PBA moieties to interact with these
molecules. (C) 2009 Elsevier B.V. All rights reserved.
著書
ソフトマターを用いるバイオデバイス (Biodevices using semiconductor materials) 松元 亮; 宮原 裕二. ソフトマター ~分子設計・キャラクタリゼーションから機能性材料まで~ (Soft matter - From molecular design and characterization to functional materials) 2009, Chapter 4.3, 222-232 (Maruzen Publishing Co. Ltd).
バイオトランジスタを用いた生体分子検出チップ (Bio-molecular detection chip using biotransistors) 松元 亮; 宮原 裕二. ヘルスケアとバイオ医療のための先端デバイス機器 (Advanced Bio/Medical Devices and Equipments for Health Care) 2009, Chapter 1, 3-12 (CMC Publishing Co., Ltd).
2008
Silk Fibroin Solution Properties Related to Assembly and Structure Matsumoto, A.; Lindsay, A.; Abedian, B.; Kaplan, D. L. Macromol. Biosci.2008, 8(11), 1006-1018. Abstract
The impact of physiological factors on silk fibroin solution properties
was studied. Specifically, the impact of fibroin concentration, protein
purity, cation type and concentration, and pH on aqueous solution
viscosity, shear behavior, and surface tension were assessed in the
context of silk protein assembly. The results demonstrate that in vitro
results could be correlated to in vivo processing events during silk
spinning. Rheological properties with reference to the amphiphilic block
structure of the protein are described, pH dependency of shear response
was quantitatively correlated to the predicted pI values of the fibroin
protein, and cooperativity among environmental factors such as pH and
salts was identified. Stabilization of silk fibroin solution states by
calcium was identified as a mode to control shear sensitivity of the
fibroin solution. The cooperativities identified suggest tight control
of fibroin aqueous solution rheological properties to gain a window of
protection against premature crystallization of the fibroin during
processing, assuring sate storage, transport, and finally successful
fiber spinning.
著書
Microbial Genetic Analysis Based on Field Effect Transistors Miyahara, Y.; Sakata, T.; Matsumoto, A. Principles of Bacterial Detection: Biosensors, Recognition Receptors and Microsystems2008, 313-339 (Springer). Abstract
In this chapter, potentiometric detection methods for microbial DNA involved recognition events by use of genetic field effect devices will be described. Fundamental principles of field effect devices and the technical background with their ongoing applications in the field of bio-sensor technologies, termed bio-FET, will be first introduced. Then concept of genetic field effect transistor will be described with emphasis on their fabrication, characteristics, and recent applications to microbial Single Nucleotide Polymorphysms (SNPs) Analysis as well as DNA sequencing. By comparing to other conventional methods, technical significance and future perspective of the genetic field effect transistor will also be discussed in detail.
2007
Silk microspheres for encapsulation and controlled release Wang, X.; Wenk, E.; Matsumoto, A.; Meinel, L.; Li, C.; Kaplan, D. L. J. Control. Release2007, 117(3), 360-370. Abstract
A method was developed to prepare silk fibroin microspheres using lipid
vesicles as templates to efficiently load protein drugs in active form
for controlled release. The lipid was subsequently removed by methanol
or sodium chloride treatments, resulting in silk microspheres consisting
of beta-sheet structure and about 2 mu m in diameter. NaCl treated
microspheres had smoother surfaces compared to the methanol treatments
based on SEM analysis, and both types of microspheres had a mixture of
multilamellar and unilamellar structures. A model protein drug,
horseradish peroxidase, was encapsulated in the microspheres.
Freeze-thaw cycles during preparation led to higher loading of the
peroxidase due to improved mixing between the silk and drug, while
without this process the drug and silk remained in separate layers or
domains in microspheres. This partitioning was determined with
fluorescein-labeled silk and rhodamine-labeled dextran. Small molecules
such as the enzyme substrate 3,31,5,5’-tetramethylbenzidine, Mw = 240
Da, and its oxidized product freely diffused through the MeOH- and
NaCl-processed silk microspheres so that enzyme loading and activity
could be determined. Enzyme activity was retained during processing and
in the final microspheres. The enzyme release profile depended on the
NaCl-process used in microsphere preparation. The physically
cross-linked P-sheet structure of silk fibroin and the residual lipids
in the microspheres played important roles in controlling enzyme release
profiles. The silk microspheres have the potential for diverse
applications where controlled protein release from biocompatible,
mechanically tough, and slowly biodegradable carriers is desirable. (c)
2006 Elsevier B.V. All rights reserved.
Silk fibroin microfluidic devices Bettinger, C. J.; Cyr, K. M.; Matsumoto, A.; Langer, R.; Borenstein, J. T.; Kaplan, D. L. Adv. Mater.2007, 19(19), 2847-2850. Abstract
Microfluidic devices were fabricated from silk ribroin using an aqueous
molding process adapted from soft lithography. The process results in
mechanically robust, patent devices with macroscopic fluidic
connections. Hepatocytes were seeded in the device and perfused for up
to five days during which they exhibited liver-specific functions
equivalent to that observed for standard tissue culture substrates.
総説
電界効果を基本原理としたバイオセンシングデバイス (Biosensing device based on electric field effect as the basic principle) 坂田 利弥; 松元 亮; 宮原 裕二. マテリアルインテグレーション (Materials integration) 2007, 20(9), 50-56.
Mechanisms of silk fibroin sol-gel transitions Matsumoto, A.; Chen, J.; Collette, A. L.; Kim, U.-J.; Altman, G. H.; Cebe, P.; Kaplan, D. L. J. Phys. Chem. B2006, 110(43), 21630-21638. Abstract
Silk fibroin sol-gel transitions were studied by monitoring the process
under various physicochemical conditions with optical spectroscopy at
550 nm. The secondary structural change of the fibroin from a disordered
state in solution to a beta-sheet-rich conformation in the gel state was
assessed by FTIR and CD over a range of fibroin concentrations,
temperatures, and pH values. The structural changes were correlated to
the degree of gelation based on changes in optical density at 550 nm. No
detectable changes in the protein secondary structure (FTIR, CD) were
found up to about 15% gelation (at 550 nm), indicating that these early
stages of gelation are not accompanied by the formation of beta-sheets.
Above 15%, the fraction of beta-sheet linearly increased with the
degree of gelation. A pH dependency of gelation time was found with
correlation to the predominant acidic side chains in the silk.
Electrostatic interactions were related to the rate of gelation above
neutral pH. The overall independencies of processing parameters
including concentration, temperature, and pH on gel formation and
protein structure can be related to primary sequence-specific features
in the molecular organization of the fibroin protein. These findings
clarify aspects of the self-assembly of this unique family of proteins
as a route to gain control of material properties, as well as for new
insight into the design of synthetic silk-biomimetic polymers with
predictable solution and assembly properties.
Fibrous proteins and tissue engineering Wang, X.; Kim, H. J.; Wong, C.; Vepari, C.; Matsumoto, A.; Kaplan, D. L. Mater. Today2006, 9(12), 44-53. Abstract
Fibrous proteins are finding broad impact in biomaterial systems for a
range of cell and tissue studies. This impact derives from an improved
insight into fundamental structure-function relationships, as well as
the unique material properties attained with these protein polymers.
Recent advances in the use of these protein systems in a variety of
biomaterial and tissue engineering applications are reviewed, with a
focus on approaches to control the structure, chemistry, and morphology
of the biomaterials formed and enable cell and tissue outcomes to be
directed in vitro and in vivo.
著書
Silk Matsumoto, A.; Kim, H. J.; Tsai, I.; Wang, X.; Cebe, P.; Kaplan, D. L. Handbook of Fiber Chemistry Third Edition2006, 383-404 (CRC Press). Abstract
Silk is an externally spun fibrous protein secretion formed into fibers, usually resulting in material structures such as cocoons or webs [1-4]. Silks are essentially pure proteins, with only in some Of all the natural silks represent the only ones that are spun. Silk fibers from silkworms have been used in textiles for nearly 5000 years. The primary reasons for this longtime use have been the unique luster, tactile properties, durability, and dyability of silks. Silk fibers are remarkable materials displaying unusual mechanical properties: strong, extensible, and mechanically compressible. Silks also display interesting thermal and electromagnetic responses, particularly in the UV range for insect entrapment and form crystalline phases related to processing. Silk fibers were used in optical instruments as late as the mid-1900s because of their fine and uniform diameter and high strength and stability over a range of temperatures and humidity. Naturalist reports suggest that some spider silks were used in the South Pacific for gill nets, dip nets, and fishing-a testimony to the remarkable mechanical properties and durability of this family of protein polymers. Silks have historically been used in medicine as sutures over the past 100 years and are currently used today in this mode along with a variety of consumer product applications. Commercially, silkworm cocoons are mass produced in a process termed ‘‘sericulture’’. The cocoons are extracted in hot soapy water to remove the sericin gluelike protein. The remaining fibroin or structural silk is reeled onto spools, yielding approximately 300-1200 m of usable thread per cocoon. These threads can be dyed or modified for textile applications. The annual world production of raw silk is about 60,000 tons, with China producing half of the world supply followed by India, Korea, and Japan. Silks represent one member of a larger class of fibrous proteins in nature, which include keratins, collagens, elastins, and others [5]. These types of proteins can be considered nature’s equivalent of synthetic block copolymers. Aside from their direct use in materials applications, fibrous proteins provide experimentally accessible model systems with simpler and well-controlled genetic template-based protein synthesis. The highly repetitive structure allows key features of the primary sequences of these proteins to be captured in shorter consensus sequences at the corresponding genetic level. Short synthetic genetic variants can then be combined to generate larger genes and thus proteins that represent mimics of the native protein. This technique is useful in simplifying the complex behavior of these proteins to an intelligible level, while retaining their biological relevance and materials function. These shorter genetic variants, when polymerized (multimerized) into longer genes, can be used to explore protein sequence and size relationships.
絹タンパク質のナノスケールでの自己組織化と構造制御 (Nanoscale features of silkworm cocoon and spider orb web silk proteins) 松元 亮; Kaplan, D. L. ’ファイバー’スーパーバイオミメティックス~近未来の新技術創成~ (’Fiber’ Superbiomimetics - The Creative Technologies in Coming Future) 2006, Part 5, Chapter 1.4, 790-798 (NTS Inc.).
2005
Processing windows for forming silk fibroin biomaterials into a 3D
porous matrix Kim, H. J.; Kim, H. S.; Matsumoto, A.; Chin, I. J.; Jin, H. J.; Kaplan, D. L. Aust. J. Chem.2005, 58(10), 716-720. Abstract
In the present study we clarify phase diagrams related to silk fibroin
processing into three-dimensional porous structures useful for
biomaterials and for scaffolds in tissue engineering. All-aqueous and
organic solvent (hexafluoroisopropanol) modes of processing are compared
relative to solution concentration of silk protein polymer and size of
porogen (NaCl particles). The results clarify the range of conditions
under which these biomaterial matrices can be formed, with a broader
range of pore sizes and smoother surface morphology generated from the
organic solvent process. These structures are directly applicable to
fundamental studies of protein-based biomaterial assembly as well as
cell interactions and tissue formation with these systems.
Biomaterial coatings by stepwise deposition of silk fibroin Wang, X. Y.; Kim, H. J.; Xu, P.; Matsumoto, A.; Kaplan, D. L. Langmuir2005, 21(24), 11335-11341. Abstract
A completely aqueous, stepwise deposition process with Bombyx mori silk
fibroin for the assembly of nanoscale thin film coatings is reported the
first time. The focus of this work was to develop an understanding of
the control of this deposition process and to characterize the films
formed from a physicochemical perspective. The deposition process was
monitored by UV spectrophotometry and research quartz crystal
microbalance. Both absorbance and film thickness correlated linearly
with the number of silk fibroin layers deposited, analogous to
multilayered materials fabricated from conventional polyelectrolytes.
The polymer adsorption process was stable and reproducible, with control
of a single layer thickness ranging from a few to tens of nanometers,
determined by the concentrations of silk fibroin, salt concentration in
the dipping solution, and method of rinsing. The driving force for the
assembly of silk fibroin onto the substrate was primarily hydrophobic
interactions, while some electrostatic interactions were also involved.
The difference with this approach from traditional polyelectrolyte
layer-by-layer techniques is that an intervening drying step is used to
control the structure and stability of the self-assembled silk fibroin.
The assembled films were stable under physiological conditions and
supported human bone marrow stem cell adhesion, growth, and
differentiation. This approach offers new options to engineer
biomaterial coatings as well as bulk materials with control of both
interfacial properties conducive to specific cellular or tissue
responses and the potential to entrap and deliver labile molecules or
other components due to the all-aqueous process described.
2004
Swelling and shrinking kinetics of totally synthetic, glucose-responsive
polymer gel bearing phenylborate derivative as a glucose-sensing moiety Matsumoto, A.; Kurata, T.; Shiino, D.; Kataoka, K. Macromolecules2004, 37(4), 1502-1510. Abstract
A glucose-responsive polymer gel bead with a diameter in the range of
several hundred micrometers, bearing a phenylborate derivative
(3-acrylamidophenylboronic acid) as a glucose-sensing moiety, was
successfully prepared by inverse phase suspension polymerization. The
kinetics of the glucose responsive swelling and shrinking process of the
gel bead was studied by monitoring changes in the size and shape of the
gel under a microscope. The equilibrium swelling volumes of the gel
determined under various temperatures and glucose concentrations
revealed the presence of critical temperatures and glucose
concentrations to induce discontinuous volume phase transitions of the
gel. The glucose-induced swelling process was accompanied by the
appearance of a marked swelling boundary (swelling front) intervening
between the core collapsed phase and the outer swollen layer of the gel,
and the swelling curve as a function of the square root of the time
exhibited a sigmoidal (nonlinear) feature, both indicating that the
process is essentially rate determined by the relaxation process of the
polymer chains due to the hydration. The swelling rate was significantly
affected by the bead size and the terminal glucose concentration. An
accelerated disappearance of the swelling front was observed immediately
before the gel reaches the equilibrium swelling, which was highlighted
by an increased bead size, implying that increasing elastic and osmotic
pressures generating from the swollen layer affect the swelling
kinetics. The glucose-induced shrinking process involved the formation
of a skin layer on the gel surface followed by a radical structural
change. The observed, appreciably long-termed preservation of a
quasi-swollen state on a sub-millimeter scale gel bead with a
distinctive skin layer may propose the potential applicability of the
gel to chemical valve systems discretely switching for solute release.
Glucose-responsive polymer gel bearing phenylborate derivative as a
glucose-sensing moiety operating at the physiological pH Matsumoto, A.; Yoshida, R.; Kataoka, K. Biomacromolecules2004, 5(3), 1038-1045. Abstract
The work attempts to prepare a totally synthetic, glucose-responsive
polymer gel bearing a phenylborate derivative as a sensor moiety to
glucose, for future use as a self-regulated insulin delivery system. The
molecular strategies to enable the system to be operated under
physiological conditions (pH 7.4, 37 degreesC) are presented that
involve the use of a novel pherylborate derivative
{4-(1,6-dioxo-2,5-diaza-7-oxamyl) phenylboronic acid: DDOPBA}
possessing an appreciably low pK(a) (similar to7.8), the adoption of
poly(Nisopropylmethacrylamide) (PNIPMAAm) for the main chain, which
itself undergoes a sharp thermo-induced phase transition at its LCST
around 40 degreesC, as well as the introduction of a carboxyl group of
methacrylic acid as the third comonomer. Glucose-responsive behaviors of
the obtained gels were evaluated based on the changes in the equilibrium
swelling degree determined in the presence and the absence of glucose,
for various pH and temperature conditions. As a consequence of the
combined molecular effects, a sufficient sensitivity of the system was
accomplished at physiological pH and in the temperature range close to
the physiological condition such as 30 degreesC. Furthermore, the
glucose-induced continuous volume changes of the gels were demonstrated
under those conditions, which occurred in a remarkably
concentration-dependent manner. In these experiments, the critical
glucose concentrations to induce the gels’ responses in the range of
normoglycemic sugar level were observed. These observations may provide
us with an excellent prospect for the use of the gel as a
self-regulated, insulin-delivery system discretely switching the release
at the normoglycemia.
2003
Glucose-responsive polymer bearing a novel phenylborate derivative as a
glucose-sensing moiety operating at physiological pH conditions Matsumoto, A.; Ikeda, S.; Harada, A.; Kataoka, K. Biomacromolecules2003, 4(5), 1410-1416. Abstract
This study is devoted to the development of novel glucose-responsive
polymers that operate under physiological conditions (pH 7.4, 37
degreesC), aiming for future use in a self-regulated insulin delivery
system to treat diabetes mellitus. The approach involves the use of a
newly synthesized phenylborate derivative
{4-(1,6-dioxo-2,5-diaza-7-oxamyl) phenylboronic acid, DDOPBA}
possessing an appreciably low pK(a) (similar to7.8) as a glucose-sensing
moiety, as well as the adoption of poly(N-isopropylmethacrylamide),
PNIPMAAm, as the main chain that exhibits critical solution behavior in
the range close to physiological temperature. Glucose-and pH-dependent
changes in the critical solution behavior of the resultant copolymers
were investigated at varying temperatures, revealing definite glucose
sensitivities near the physiological conditions. Furthermore, DDOPBA
moieties in the copolymers maintained constant apparent pK(a) values
even when the temperature approaches the critical solution points of the
main chain, indicating that spacing of the phenylborate moiety from the
polymer backbone is a feasible way to minimize the microenvironment
effect caused by a temperature-induced change in the hydration state of
the polymer strands.