Faculty Profiles - NISHINA Yuta

Papers - NISHINA Yuta

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Dynamic nuclear polarization – nuclear magnetic resonance for analyzing surface functional groups on carbonaceous materials

Hideka Ando, Katsuaki Suzuki, Hironori Kaji, Takashi Kambe, Yuta Nishina, Chiyu Nakano, Kazuma Gotoh

Carbon 206 84 - 93 2023.3

Publishing type：Research paper (scientific journal) Publisher：Elsevier BV

Dynamic nuclear polarizing (DNP) technique in nuclear magnetic resonance (NMR) is a powerful tool for a microanalysis. Nevertheless, it has not been applied to analyses of carbon materials such as graphene oxide (GO) and amorphous carbon effectively because of the electroconductivity and microwave absorption of the carbon, which attenuate the enhancement effect of DNP. For this study, we applied DNP-NMR to analyses of surface functional groups on GO and sucrose-derived carbon to evaluate the method. The 1H–13C cross-polarization magic-angle spinning (CP/MAS) DNP-NMR of a GO sample with AMUPol (polarizing agent) showed 2.2-times-enhanced peaks of 13C in epoxide, bonding to hydroxyl group, and in the graphene plane. Signal enhancement was raised by AMUPol radicals neighboring the surface functional groups and the graphene planes on GO particles, although attenuation by temperature rise must be considered. Furthermore, additional new peaks assigned to CH3 group on the GO particle surface were highly enhanced and were observed clearly only by the accumulations of 64 scans. For sucrose-derived carbon, DNP-NMR clearly revealed the –OH group on the carbon surface or carbon edge by heat treatment, which was not possible using conventional CP/MAS experiments. Cross Effect was found to be dominant in signal enhancements of the functional groups on GO and sucrose-derived carbon samples, except for the CH3 groups on GO. The CH3 enhancement is ascribed mainly to the Overhauser effect or solid effect.

DOI： 10.1016/j.carbon.2023.02.010

Self-Assembly Strategies for Graphene Oxide/Silica Nanostructures: Synthesis and Structural Analysis

Yuki Takeuchi, Kentaro Ohkura, Yuta Nishina

Bulletin of the Chemical Society of Japan 96 ( 2 ) 113 - 119 2023.2

Publishing type：Research paper (scientific journal)

Nanostructured 3D silica-based materials can be designed using a low-dimensional template. Various composites composed of graphene oxide (GO) and silica have been investigated. However, to improve the performance of GO/silica nanostructure (GSN), the exploitation of the assembly method and the effect of combining GO and silica on the hybrid structure need to be elucidated. In this study, novel mesoporous GSNs were developed using two self-assembly methods: particle attaching-induced self-assembly (PAISA) and polymerization- and evaporation-induced self-assembly (PEISA). The synthesized GSNs obtained using each method were analyzed to determine the effect of combining silica with GO in each method on the porosity of GSNs. The former method introduced silica nanoparticles into GO, and aligned pores similar to the particle size were formed. In the latter method, synthesized GSN had broad mesopores, and a higher surface area derived from the silica particles randomly formed inside/outside GO layers. Both GSNs have specific surface areas close to that of the introduced silica, suggesting that the porosity of GSNs can be controlled by selecting the appropriate silica structure and its synthesis. Furthermore, GSN had a higher pore volume than silica itself, suggesting the formation of a hierarchical structure by introducing GO.

DOI： 10.1246/bcsj.20220279

Non-enzymatic detection of glucose levels in human blood plasma by a graphene oxide-modified organic transistor sensor International journal

Haonan Fan, Yui Sasaki, Qi Zhou, Wei Tang, Yuta Nishina, Tsuyoshi Minami

Chemical Communications 59 ( 17 ) 2425 - 2428 2023.1

Language：English Publishing type：Research paper (scientific journal)

We herein report an organic transistor functionalized with a phenylboronic acid derivative and graphene oxide for the quantification of plasma glucose levels, which has been achieved by the minimization of interferent effects derived from physical protein adsorption on the detection electrode.

DOI： 10.1039/d2cc07009j

Angstrom-Confined Electrochemical Synthesis of Sub-Unit-Cell Non-Van Der Waals 2D Metal Oxides International journal

Dali Ji, Yunah Lee, Yuta Nishina, Kazuhide Kamiya, Rahman Daiyan, Dewei Chu, Xinyue Wen, Masamichi Yoshimura, Priyank Kumar, Daria V. Andreeva, Kostya S. Novoselov, Gwan Hyoung Lee, Rakesh Joshi, Tobias Foller

Advanced Materials 35 ( 30 ) e2301506 2023

Language：English Publishing type：Research paper (scientific journal)

Bottom-up electrochemical synthesis of atomically thin materials is desirable yet challenging, especially for non-vanderWaals (non–vdW) materials. Thicknesses below a few nanometers have not been reported yet, posing the question how thin can non-vdW materials be electrochemically synthesized. This is important as materials with (sub-)unit–cell thickness often show remarkably different properties compared to their bulk form or thin films of several nanometers thickness. Here, a straightforward electrochemical method utilizing the angstrom-confinement of laminar reduced graphene oxide (rGO) nanochannels is introduced to obtain a centimeter-scale network of atomically thin (<4.3 Å) 2D-transition metal oxides (2D-TMO). The angstrom-confinement provides a thickness limitation, forcing sub-unit–cell growth of 2D-TMO with oxygen and metal vacancies. It is showcased that Cr2O3, a material without significant catalytic activity for the oxygen evolution reaction (OER) in bulk form, can be activated as a high-performing catalyst if synthesized in the 2D sub-unit–cell form. This method displays the high activity of sub-unit–cell form while retaining the stability of bulk form, promising to yield unexplored fundamental science and applications. It is shown that while retaining the advantages of bottom-up electrochemical synthesis, like simplicity, high yield, and mild conditions, the thickness of TMO can be limited to sub-unit–cell dimensions.

DOI： 10.1002/adma.202301506

Polymyxin B complexation enhances the antimicrobial potential of graphene oxide. International journal

Santosh Pandit, Lucas Jacquemin, Jian Zhang, Zhengfeng Gao, Yuta Nishina, Rikke Louise Meyer, Ivan Mijakovic, Alberto Bianco, Chengfang Pang

Frontiers in cellular and infection microbiology 13 1209563 - 1209563 2023

Language：English Publishing type：Research paper (scientific journal)

INTRODUCTION: The antibacterial activity of graphene oxide (GO) has been widely explored and tested against various pathogenic bacterial strains. Although antimicrobial activity of GO against planktonic bacterial cells was demonstrated, its bacteriostatic and bactericidal effect alone is not sufficient to damage sedentary and well protected bacterial cells inside biofilms. Thus, to be utilized as an effective antibacterial agent, it is necessary to improve the antibacterial activity of GO either by integration with other nanomaterials or by attachment of antimicrobial agents. In this study, antimicrobial peptide polymyxin B (PMB) was adsorbed onto the surface of pristine GO and GO functionalized with triethylene glycol. METHODS: The antibacterial effects of the resulting materials were examined by evaluating minimum inhibitory concentration, minimum bactericidal concentration, time kill assay, live/dead viability staining and scanning electron microscopy. RESULTS AND DISCUSSION: PMB adsorption significantly enhanced the bacteriostatic and bactericidal activity of GO against both planktonic cells and bacterial cells in biofilms. Furthermore, the coatings of PMB-adsorbed GO applied to catheter tubes strongly mitigated biofilm formation, by preventing bacterial adhesion and killing the bacterial cells that managed to attach. The presented results suggest that antibacterial peptide absorption can significantly enhance the antibacterial activity of GO and the resulting material can be effectively used not only against planktonic bacteria but also against infectious biofilms.

DOI： 10.3389/fcimb.2023.1209563

Erratum: Bonding of Neuropeptide Y on Graphene Oxide for Drug Delivery Applications to the Central Nervous System (ACS Applied Nano Materials (2022) 5: 12 (17640−17651) DOI: 10.1021/acsanm.2c03409)

Cellot, G., Jacquemin, L., Reina, G., Franceschi Biagioni, A., Fontanini, M., Chaloin, O., Nishina, Y., Bianco, A., Ballerini, L.

ACS Applied Nano Materials 6 ( 9 ) 8105 - 8105 2023

Photocatalytic Dehydrogenation of N-Heterocycles Promoted by Radicals from Graphene Oxide

Ahmed, M.R., Nishina, Y.

Bulletin of the Chemical Society of Japan 96 ( 6 ) 2023

Iron-Added Sediment Microbial Fuel Cells to Suppress Phosphorus Release from Sediment in an Agricultural Drainage

Perera, G.L.E.P., Maeda, M., Somura, H., Nakano, C., Nishina, Y.

Journal of Water and Environment Technology 21 ( 5 ) 2023

Bonding of Neuropeptide Y on Graphene Oxide for Drug Delivery Applications to the Central Nervous System International journal

Giada Cellot, Lucas Jacquemin, Giacomo Reina, Audrey Franceschi Biagioni, Mario Fontanini, Olivier Chaloin, Yuta Nishina, Alberto Bianco, Laura Ballerini

ACS Applied Nano Materials 5 ( 12 ) 17640 - 17651 2022.12

Language：English Publishing type：Research paper (scientific journal)

Nanoscale graphene-based materials (GBMs) enable targeting subcellular structures of the nervous system, a feature crucial for the successful engineering of alternative nanocarriers to deliver drugs and to treat neurodisorders. Among GBMs, graphene oxide (GO) nanoflakes, showing good dispersibility in water solution and being rich of functionalizable oxygen groups, are ideal core structures for carrying biological active molecules to the brain, such as the neuropeptide Y (NPY). In addition, when unconjugated, these nanomaterials have been reported to modulate neuronal function per se. Although some GBM-based nanocarriers have been tested both in vitro and in vivo, a thorough characterization of covalent binding impact on the biological properties of the carried molecule and/or of the nanomaterial is still missing. Here, a copper(I)-catalyzed alkyne-azide cycloaddition strategy was employed to synthesize the GO-NPY complex. By investigating through electrophysiology the impact of these conjugates on the activity of hippocampal neurons, we show that the covalent modification of the nanomaterial, while making GO an inert platform for the vectorized delivery, enhances the duration of NPY pharmacological activity. These findings support the future use of GO for the development of smart platforms for nervous system drug delivery.

DOI： 10.1021/acsanm.2c03409

Graphene Oxide-based Endodontic Sealer: An in Vitro Study.

Mohammed Zahedul Islam Nizami, Melahat Gorduysus, Yuki Shinoda-Ito, Tadashi Yamamoto, Yuta Nishina, Shogo Takashiba, Zulema Arias

Acta medica Okayama 76 ( 6 ) 715 - 721 2022.12

Language：English Publishing type：Research paper (scientific journal)

The failure of endodontic treatment is directly associated with microbial infection in the root canal or periapical areas. An endodontic sealer that is both bactericidal and biocompatible is essential for the success of root canal treatments. This is one of the vital issues yet to be solved in clinical dental practice. This in vitro study assessed the effectiveness of graphene oxide (GO) composites GO-CaF2 and GO-Ag-CaF2 as endodontic sealer materials. Dentin slices were coated with either the GO-based composites or commonly used root canal sealers (non-eugenol zinc oxide sealer). The coated slices were treated in 0.9% NaCl, phosphate-buffered saline (PBS), and simulated body fluid (SBF) at 37˚C for 24 hours to compare their sealing effect on the dentin surface. In addition, the radiopacity of these composites was examined to assess whether they complied with the requirements of a sealer for good radiographic visualization. Scanning electron microscopy showed the significant sealing capability of the composites as coating materials. Radiographic images confirmed their radiopacity. Mineral deposition indicated their bioactivity, especially of GO-Ag-CaF2, and thus it is potential for regenerative application. They were both previously shown to be bactericidal to oral microbes and cytocompatible with host cells. With such a unique assemblage of critical properties, these GO-based composites show promise as endodontic sealers for protection against reinfection in root canal treatment and enhanced success in endodontic treatment overall.

DOI： 10.18926/AMO/64122

酸化グラフェンと塩化セチルピリジニウムを応用した不織布マスクの抗菌性

越宗朋隆, 伊東有希[信田], 仁科勇太, 高柴正悟

岡山歯学会雑誌 41 ( 2 ) 60 - 61 2022.12

In Situ Synthesis of Ultrathin Amorphous Silica Nanosheet with Large Specific Surface Area on Graphene Oxide

Yuki Takeuchi, Seiji Obata, Kentaro Ohkura, Yuta Nishina

ACS Materials Letters 4 ( 12 ) 2590 - 2596 2022.11

Stacking order reduction in multilayer graphene by inserting nanospacers

Zizhao Xu, Taiki Inoue, Yuta Nishina, Yoshihiro Kobayashi

Journal of Applied Physics 132 ( 17 ) 174305 - 174305 2022.11

Publishing type：Research paper (scientific journal) Publisher：AIP Publishing

Toward macroscopic applications of graphene, it is desirable to preserve the superior properties of single-layer graphene in bulk scale. However, the AB-stacking structure is thermodynamically favored for multilayer graphene and causes strong interlayer interactions, resulting in property degradation. A promising approach to prevent the strong interlayer interaction is the staking order reduction of graphene, where the graphene layers are rotated in-plane to form a randomly stacking structure. In this study, we propose a strategy to effectively decrease the stacking order of multilayer graphene by incorporating nanospacers, cellulose nanofibers, or nano-diamonds (NDs) in the formation process of porous graphene sponges. We conducted an ultrahigh temperature treatment at 1500 °C with ethanol vapor for the reduction and structural repair of graphene oxide sponges with different concentrations of the nanospacers. Raman spectroscopy indicated an obvious increase in the random-stacking fraction of graphene by adding the nanospacers. The x-ray diffraction (XRD) analysis revealed that a small amount of the nanospacers induced a remarkable decrease in ordered graphene crystalline size in the stacking direction. It was also confirmed that a layer-number increase during the thermal treatment was suppressed by the nanospacers. The increase in the random-stacking fraction is attributed to the efficient formation of randomly rotated graphene through the ethanol-mediated structural restoration of relatively thin layers induced by the nanospacers. This stacking-order-reduced graphene with bulk scale is expected to be used in macroscopic applications, such as electrode materials and wearable devices.

DOI： 10.1063/5.0103826

Electrodeposition of hydroxyapatite and graphene oxide improves the bioactivity of medical grade stainless steel

M. Z.I. Nizami, B. D.L. Campéon, Y. Nishina

Materials Today Sustainability 19 2022.11

Publishing type：Research paper (scientific journal)

The improvement of bioactivity, biocompatibility, and corrosion resistance of metal substrates are the common goals in biomaterials research. Graphene oxide (GO) for its outstanding chemical and mechanical properties has attracted researchers. Relatively, Hydroxyapatite (HA) has been employed as a biocompatible coating material to improve bone fixation property, durability, and osteointegration of an implant. Therefore, in this study, a composite of GO and HA (GO-HA) was coated on medical grade stainless steel (MS 316L) substrate by anodic electrochemical deposition to improve mechanical peeling resistance, corrosion resistance, and bioactivity. The coating's morphology and ability to cover the substrate surface were analyzed by SEM-EDS, XPS, and the surface roughness by AFM. The coating's structural properties were analyzed with Raman spectroscopy. The investigation of corrosion inhibition involved open circuit potential, EIS, and Voltammetry analysis. The standard salt test, an American Society for Testing and Materials (ASTM) G48A for stainless steel substrate, has also been studied. The bioactivity of the coated substrates was investigated in simulated body fluid (SBF). Significant enhancement of corrosion potential as well as bioactivity of the coated substrates has been achieved. GO-HA coating onto MS 316L was strongly adherent, uniform, and able to provide optimum surface roughness. Hence, the combination of the improved surface properties and bioactivity indicates that GO-HA coating can be utilized to overcome apposite limitations of bare MS 316L surface in clinical settings.

DOI： 10.1016/j.mtsust.2022.100193

Fabrication of binderless electrodes via non-destructive electrochemical oxidation/reduction of graphite sheets using BF<inf>4</inf> salts

Masato Komoda, Yuta Nishina

Electrochimica Acta 430 2022.10

Publishing type：Research paper (scientific journal)

We report the electrochemical oxidation of graphite sheets using BF4 salts, and direct electrochemical reduction of its product to prepare two-dimensional carbon materials efficiently. Electrochemical oxidation enables the synthesis of graphene oxide (GO) under milder conditions than those required for chemical oxidation, e.g., a strong oxidant in concentrated acid. In this work, graphite sheet was electrochemically oxidized with BF4 salt electrolyte solution, and its product was electrochemically reduced in PBS. In the present method, the use of BF4 salt allows the successful electrochemical synthesis of high-quality, uniform GO without the use of an acid. Furthermore, the non-destructive nature of the method provides a GO product that can be subjected to electrochemical reduction to form reduced GO. Thus, the method provides facile access to high-quality two-dimensional carbon materials in a manner that has the potential for mass production.

DOI： 10.1016/j.electacta.2022.141087

Development of a Multitimescale Time-Resolved Electron Diffraction Setup: Photoinduced Dynamics of Oxygen Radicals on Graphene Oxide International journal

Yuri Saida, Ryo Shikata, Kaito En-Ya, Satoshi Ohmura, Yuta Nishina, Masaki Hada

Journal of Physical Chemistry A 126 ( 36 ) 6301 - 6308 2022.9

Language：English Publishing type：Research paper (scientific journal)

We developed a multitimescale time-resolved electron diffraction setup by electrically synchronizing a nanosecond laser with our table-top picosecond time-resolved electron diffractometer. The setup covers the photoinduced structural dynamics of target materials at timescales ranging from picoseconds to submilliseconds. Using this setup, we sequentially observed the ultraviolet (UV) photoinduced bond dissociation, radical formation, and relaxation dynamics of the oxygen atoms in the epoxy functional group on the basal plane of graphene oxide (GO). The results show that oxygen radicals formed via UV photoexcitation on the basal plane of GO in several tens of picoseconds and then relaxed back to the initial state on the microsecond timescale. The results of first-principles calculations also support the formation of oxygen radicals in the excited state on an early timescale. These results are essential for the further discussion of the reactivities on the basal plane of GO, such as catalytic reactions and antibacterial and antiviral activities. The results also suggest that the multitimescale time-resolved electron diffraction system is a promising tool for laboratory-based molecular dynamics studies of materials and chemical systems.

DOI： 10.1021/acs.jpca.2c04075

Optimizing the structure and molecular weight of polymers for graphene dispersants

Shimpei Takeda, Yuta Nishina

Polymer Journal 54 ( 11 ) 1377 - 1381 2022.8

Language：English Publishing type：Research paper (scientific journal) Publisher：SPRINGERNATURE

Graphene is an allotrope of carbon consisting of a single-atom-thick honeycomb lattice nanostructure. Among the various preparation methods for graphene, the liquid-phase exfoliation of graphite is mass-producible and cost-effective. To facilitate the exfoliation of graphite in organic solvents, polymers can be employed as dispersants. We synthesized polymer dispersants with various monomer ratios and molecular weights and investigated the efficient acquisition of graphene from graphite. Graphene with a uniform thickness was obtained when graphite was exfoliated using an optimized polymer dispersant. The optimized polymer enabled a high yield and concentration of graphene using liquid-phase exfoliation.

DOI： 10.1038/s41428-022-00684-2

Growth of ZIF-8 Nanoparticles In Situ on Graphene Oxide Nanosheets: A Multifunctional Nanoplatform for Combined Ion-Interference and Photothermal Therapy International journal

Chunxu Lv, Wenyan Kang, Shuo Liu, Pishan Yang, Yuta Nishina, Shaohua Ge, Alberto Bianco, Baojin Ma

ACS Nano 16 ( 7 ) 11428 - 11443 2022.7

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC

The regulation of intracellular ions' overload to interrupt normal bioprocesses and cause cell death has been developed as an efficient strategy (named as ion-interference therapy/IIT) to treat cancer. In this study, we design a multifunctional nanoplatform (called BSArGO@ZIF-8 NSs) by in situ growth of metal organic framework nanoparticles (ZIF-8 NPs) onto the graphene oxide (GO) surface, subsequently reduced by ascorbic acid and modified by bovine serum albumin. This nanocomplex causes the intracellular overload of Zn2+, an increase of reactive oxygen species (ROS), and exerts a broad-spectrum lethality to different kinds of cancer cells. BSArGO@ZIF-8 NSs can promote cell apoptosis by initiating bim (a pro-apoptotic protein)-mediated mitochondrial apoptotic events, up-regulating PUMA/ NOXA expression, and down-regulating the level of Bid/p53AIP1. Meanwhile, Zn2+ excess triggers cellular dysfunction and mitochondria damage by activating the autophagy signaling pathways and disturbing the intracellular environmental homeo-stasis. Combined with the photothermal effect of reduced GO (rGO), BSArGO@ZIF-8 NSs mediated ion-interference and photothermal combined therapy leads to effective apoptosis and inhibits cell proliferation and angiogenesis, bringing a higher efficacy in tumor suppression in vivo. This designed Zn-based multifunctional nanoplatform will allow promoting further the development of IIT and the corresponding combined cancer therapy strategy.

DOI： 10.1021/acsnano.2c05532

Combined Photothermal and Photodynamic Therapy for Cancer Treatment Using a Multifunctional Graphene Oxide International journal

Shi Guo, Zhengmei Song, Ding-Kun Ji, Giacomo Reina, Jean-Daniel Fauny, Yuta Nishina, Cecilia Menard-Moyon, Alberto Bianco

Pharmaceutics 14 ( 7 ) 2022.7

Language：English Publishing type：Research paper (scientific journal) Publisher：MDPI

Graphene oxide (GO) is one of the most studied nanomaterials in many fields, including the biomedical field. Most of the nanomaterials developed for drug delivery and phototherapies are based on noncovalent approaches that lead to an unspecific release of physisorbed molecules in complex biological environments. Therefore, preparing covalently functionalized GO using straightforward and versatile methods is highly valuable. Phototherapies, including photothermal therapy (PTT) and photodynamic therapy (PDT), have shown great potential as effective therapeutic approaches against cancer. To overcome the limits of a single method, the combination of PTT and PDT can lead to a combined effect with a higher therapeutic efficiency. In this work, we prepare a folic acid (FA) and chlorin e6 (Ce6) double-functionalized GO for combined targeted PTT/PDT. This conjugate can penetrate rapidly into cancer cells and macrophages. A combined effect of PTT and PDT is observed, leading to a higher killing efficiency toward different types of cells involved in cancer and other diseases. Our work provides a simple protocol to prepare multifunctional platforms for the treatment of various diseases.

DOI： 10.3390/pharmaceutics14071365

Nanocellulose Paper Semiconductor with a 3D Network Structure and Its Nano–Micro–Macro Trans-Scale Design

Hirotaka Koga, Kazuki Nagashima, Koichi Suematsu, Tsunaki Takahashi, Luting Zhu, Daiki Fukushima, Yintong Huang, Ryo Nakagawa, Jiangyang Liu, Kojiro Uetani, Masaya Nogi, Takeshi Yanagida, Yuta Nishina

ACS Nano 16 ( 6 ) 8630 - 8640 2022.6

Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society (ACS)

Semiconducting nanomaterials with 3D network structures exhibit various fascinating properties such as electrical conduction, high permeability, and large surface areas, which are beneficial for adsorption, separation, and sensing applications. However, research on these materials is substantially restricted by the limited trans-scalability of their structural design and tunability of electrical conductivity. To overcome this challenge, a pyrolyzed cellulose nanofiber paper (CNP) semiconductor with a 3D network structure is proposed. Its nano-micro-macro trans-scale structural design is achieved by a combination of iodine-mediated morphology-retaining pyrolysis with spatially controlled drying of a cellulose nanofiber dispersion and paper-crafting techniques, such as microembossing, origami, and kirigami. The electrical conduction of this semiconductor is widely and systematically tuned, via the temperature-controlled progressive pyrolysis of CNP, from insulating (10(12) Omega cm) to quasimetallic (10(-2) Omega cm), which considerably exceeds that attained in other previously reported nanomaterials with 3D networks. The pyrolyzed CNP semiconductor provides not only the tailorable functionality for applications ranging from water-vapor-selective sensors to enzymatic biofuel cell electrodes but also the designability of macroscopic device configurations for stretchable and wearable applications. This study provides a pathway to realize structurally and functionally designable semiconducting nanomaterials and all-nanocellulose semiconducting technology for diverse electronics.

DOI： 10.1021/acsnano.1c10728

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