教員・研究者詳細 - 臼井　健二

論文 - 臼井　健二

分割表示 87 件中 1 - 20 件目／全件表示 >>

One-Pot Synthesis and Immobilization of Gold Nanoparticles Using Peptidyl Microbeads

Shuhei Yoshida, Koki Yoshida, Taichi Isozaki, Maho Oura, Makoto Ozaki, Takaaki Tsuruoka, Kenji Usui

Molecules 30 1689 2025年4月

Development of detection system for lead ions in mixture solutions using UV-Vis measurements with peptide immobilized microbeads

Shuhei Yoshida, Koki Yoshida, Yoshio Hamada, Takaaki Tsuruoka, Kenji Usui

Scientific Reports 15 3249 2025年1月

Complex and Non-sequential Current Signatures of a β-Hairpin Peptide Confined in a Nanopore 国際共著

Misa Yamaji, Mauro Chinappi, Blasco Morozzo della Rocca, Kenji Usui, Ryuji Kawano

Analytical Chemistry 97 2044 - 2051 2025年1月

出版者・発行元：American Chemical Society (ACS)

DOI： 10.1021/acs.analchem.4c04150

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Development of a CaCO3 Precipitation Method Using a Peptide and Microwaves Generated by a Magnetron 査読あり

Fumihiro Kayamori, Hiroyuki Togashi, Natsumi Endo, Makoto Ozaki, Kan Hirao, Yonejiro Arimoto, Ryuji Osawa, Takaaki Tsuruoka, Takahito Imai, Kin-ya Tomizaki, Tomohiro Umetani, Nobuhiro Nakanishi, Kenji Usui

Processes 12 1327 - 1327 2024年6月

出版者・発行元：MDPI AG

Microwave applications, such as microwave ovens and mobile phones, are ubiquitous and indispensable in modern society. As the utilization of microwave technology is becoming more widespread, the effects of microwaves on living organisms and physiological processes have received increased attention. This study aimed to investigate the effects of microwaves on calcium carbonate biomineralization as a model biochemical process. A magnetron oscillator was used to generate 2450 MHz microwaves because magnetrons are relatively inexpensive and widespread. We conducted transmission electron microscopy (TEM), atomic force microscopy (AFM), TEM-electron energy-loss spectroscopy (EELS), dynamic light scattering (DLS), and high-performance liquid chromatography (HPLC) measurements to analyze the calcium carbonate precipitates. Our findings showed the formation of string-like precipitates of calcium carbonate upon microwave irradiation from one direction, similar to those obtained using a semiconductor oscillator, as reported previously. This implied that the distribution of the frequency had little effect on the morphology. Furthermore, spherical precipitates were obtained upon microwave irradiation from two directions, indicating that the morphology could be controlled by varying the direction of microwave irradiation. Magnetrons are versatile and also used in large-scale production; thus, this method has potential in medical and industrial applications.

DOI： 10.3390/pr12071327

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Effect of linearly polarized microwaves on nanomorphology of calcium carbonate mineralization using peptides 査読あり

Kenji Usui, Makoto Ozaki, Kan Hirao, Tsubasa Kosaka, Natsumi Endo, Shuhei Yoshida, Shin-ichiro Yokota, Yonejiro Arimoto, Ryuji Osawa, Nobuhiro Nakanishi, Kin-ya Tomizaki, Tomohiro Umetani, Fumihiro Kayamori

Scientific Reports 13 12027 2023年7月

Microwaves are used for diverse applications such as mobile phones, ovens, and therapy devices. However, there are few reports on the effects of microwaves on diseases other than cancer, and on physiological processes. Here, we focused on CaCO3 mineralization as a model of biomineralization and attempted to elucidate the effect of microwaves on CaCO3 mineralization using peptides. We conducted AFM, ζ potential, HPLC, ICP-AES, and relative permittivity measurements. Our findings show that microwaves alter the nanomorphology of the CaCO3 precipitate, from sphere-like particles to string-like structures. Furthermore, microwaves have little effect on the mineralization when the mineralization ability of a peptide is high, but a large effect when the precipitation ability is low. Our findings may be applicable to not only the treatment of teeth and bones but also the development of organic–inorganic nanobiomaterials. This methodology can be expanded to other molecular/atomic reactions under various microwave conditions to alter reaction activity parameters.

Construction of a Method to Design Fibril-Forming Peptides Applied to Biomaterials from 20 Beta-Sheet Peptides by Statistical Analysis 査読あり

Kazuya Iwata, Taisei Terao, Akira Takekawa, Tomohiro Umetani, Kenji Usui

Peptide Science 2022 141 - 142 2023年3月

担当区分：最終著者,　責任著者

De novo design of a nanopore for single-molecule detection that incorporates a β-hairpin peptide. 査読あり国際共著国際誌

Keisuke Shimizu, Batsaikhan Mijiddorj, Masataka Usami, Ikuro Mizoguchi, Shuhei Yoshida, Shiori Akayama, Yoshio Hamada, Akifumi Ohyama, Kenji Usui, Izuru Kawamura, Ryuji Kawano

Nature nanotechnology 17 67 - 75 2022年1月

The amino-acid sequence of a protein encodes information on its three-dimensional structure and specific functionality. De novo design has emerged as a method to manipulate the primary structure for the development of artificial proteins and peptides with desired functionality. This paper describes the de novo design of a pore-forming peptide, named SV28, that has a β-hairpin structure and assembles to form a stable nanopore in a bilayer lipid membrane. This large synthetic nanopore is an entirely artificial device for practical applications. The peptide forms multidispersely sized nanopore structures ranging from 1.7 to 6.3 nm in diameter and can detect DNAs. To form a monodispersely sized nanopore, we redesigned the SV28 by introducing a glycine-kink mutation. The resulting redesigned peptide forms a monodisperse pore with a diameter of 1.7 nm leading to detection of a single polypeptide chain. Such de novo design of a β-hairpin peptide has the potential to create artificial nanopores, which can be size adjusted to a target molecule.

DOI： 10.1038/s41565-021-01008-w

PubMed

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ウォッシャーディスインフェクターのすすぎ排水中に含まれる洗浄剤残留量の測定によるすすぎ性能評価査読あり

三軒隼人、藤田敏、川田原瑠勇、武川公、臼井健二、原田陽滋

医療機器学 91 315 - 332 2021年8月

Intracellular mineralization of gold nanoparticles using gold ion-binding peptides with cell-penetrating ability 査読あり

Ozaki, M., Yoshida, S., Tsuruoka, T., Usui, K.

Chemical Communications 57 2021年

共著

担当区分：最終著者,　責任著者

DOI： 10.1039/d0cc06117d