研究者詳細 - 今中　洋行

論文 - 今中　洋行

分割表示 110 件中 1 - 20 件目／全件表示 >>

Avoidance of crystallization of hydrophobic drugs in an amorphous solid dispersion during spray-drying and storage

Rina Yamamoto, Hiroyuki Imanaka, Naoyuki Ishida, Koreyoshi Imamura

Drying Technology 42 ( 13 ) 2022 - 2031 2024年9月

Flavor retention characteristics of amorphous solid dispersion of flavors, prepared by vacuum-foam- and spray-drying under different conditions

Yuna Nitta, Haruna Sato, Rina Yamamoto, Hiroyuki Imanaka, Naoyuki Ishida, Koreyoshi Imamura

Drying Technology 1 - 11 2023年11月

Water sorption and glass-to-rubber transition of amorphous sugar matrices, vacuum foam- and spray-dried from alcohols

Koji Takeda, Shinta Miyazaki, Takashi Okamoto, Hiroyuki Imanaka, Naoyuki Ishida, Koreyoshi Imamura

JOURNAL OF FOOD ENGINEERING 349 2023年7月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ELSEVIER SCI LTD

The objective of this study is to understand the impact of preparation conditions on the physicochemical characteristics of amorphous sugar. Amorphous sugar (alpha-maltose, isomaltulose, trehalose) matrices were pre -pared from alcohol (methanol, ethanol) solutions, and their water sorption behavior and glass transition tem-peratures, Tg, were compared with those of aqueous freeze-dried amorphous sugar. Vacuum-foam-and spray -drying procedures were employed as drying methods. Water sorption for amorphous sugars, dried by different methods, was generally significant in the following order: vacuum-foam-drying < spray-drying <= freeze-drying. In the same order, the Tg values for the thoroughly dried amorphous sugars increased, and water sorption reduced the differences in Tg for given amounts of sorbed water. The solvent type in vacuum-foam-drying slightly affected the water sorption and the dependence of Tg on the sorbed water amount. The obtained findings sug-gested that physicochemical characteristics of amorphous sugar may relate to the sugar molecule conformations in solvent and dried state.

DOI： 10.1016/j.jfoodeng.2023.111483

Web of Science

researchmap

Kinetics of Enzymatic Reactions at the Solid/Liquid Interface in Nanofluidic Channels

Koki Yamamoto, Kyojiro Morikawa, Hiroyuki Imanaka, Koreyoshi Imamura, Takehiko Kitamori

Analytical Chemistry 2022年10月

Extraordinary high preservation of the dispersion state of Au nanoparticles during freeze-thawing and freeze-drying with gum arabic

Miki Kadowaki, Tsutashi Matsuura, Hiroyuki Imanaka, Naoyuki Ishida, Koreyoshi Imamura

Colloids and Surfaces A: Physicochemical and Engineering Aspects 639 2022年4月

掲載種別：研究論文（学術雑誌）

A series of edible and non-toxic substances were screened for their ability to prevent Au nanoparticles (AuNPs) from undergoing aggregation during both freeze-thawing and freeze-drying at as low an additive concentration as possible. Gum arabic was found to be an ideal choice. The addition of 20 µg/mL of gum arabic greatly inhibited the aggregation of AuNPs during freeze-thawing and -drying, whereas polyvinylpyrrolidone was the next best among the tested substances, with approximately 20% aggregation during freeze-drying at a concentration of less than 200 µg/mL. The zeta potential value of the AuNPs indicated the absence of the specific binding of gum arabic to the AuNPs surface. Surface enhanced infrared spectroscopic (SEIRAS) analyses were conducted for the gum arabic solution, frozen and freeze-dried on the Au particles. The results indicated that, in the frozen state, gum arabic molecules were concentrated in remaining unfrozen liquid on the Au coating without any specific orientation toward the Au surface. In contrast, SEIRAS spectra of freeze-dried gum arabic indicated that carboxylic groups in gum arabic molecules preferentially became closer to the Au surface. Considering these findings, during freeze-thawing, we conclude that the high thickening property of gum arabic gum plays an important role in minimizing the mobility and thus the aggregation of AuNPs in the freeze-concentrated regions between frozen ice crystals. The freeze-drying of a gum arabic solution produces a rigid amorphous matrix that has an affinity for the Au surface. The AuNPs were individually separated and immobilized in the freeze-dried matrix of the gum arabic, resulting in the extraordinary inhibition of their aggregation.

DOI： 10.1016/j.colsurfa.2022.128392

Scopus

researchmap

Comparison of improvements of aqueous dissolution of structurally analogous hydrophobic drugs by amorphous solid dispersion

Takashi Okamoto, Kayoko Yamamoto, Takanari Sekitoh, Akiho Fujioka, Hiroyuki Imanaka, Naoyuki Ishida, Koreyoshi Imamura

Colloids and Surfaces A: Physicochemical and Engineering Aspects 632 127744 - 127744 2022年1月

Foaming characteristics of sugar- and polyvinylpyrrolidone-alcohol solutions during vacuum foam drying: A rheological approach

Olivier Tramis, Akiho Fujioka, Hiroyuki Imanaka, Naoyuki Ishida, Koreyoshi Imamura

COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS 627 2021年10月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ELSEVIER

Vacuum foam drying offers great perspectives to formulate solid-state encapsulated active drugs. Taking into account the specific need of pharmaceutical formulations to keep drug molecules active and dispersed, we show in this paper that vacuum drying of pharmaceutical formulations can be substantially improved by using original rheological approaches. Typically, our formulations totally dried-up in less than 5 min, a delay much shorter than the long hours of the traditional vacuum drying process. Steady-shear rheology was used to evaluate the solution's specific viscosity against the solutions' concentrations, in order to correlate the dilution regime to the foamabiltiy. This rheological approach indicated that in miscible solutions, spontaneous foaming occurred in the semi-dilute entangled regime, near the transition to the concentrated regime; for partially miscible solutions, it occurred in solutions at a concentration near to the percolation concentration. The proposed methodology is versatile, and should provide a simple way to assess the foamability of pharmaceutical formulations.

DOI： 10.1016/j.colsurfa.2021.127174

Web of Science

researchmap

Inhibiting Au nanoparticle aggregation in freeze-thawing by presence of various additives

Miki Kadowaki, Hidetaka Yokota, Hiroyuki Imanaka, Naoyuki Ishida, Koreyoshi Imamura

Advanced Powder Technology 32 ( 10 ) 3517 - 3524 2021年10月

Direct measurements of interaction forces of bovine serum albumin and lysozyme with stainless steel by atomic force microscopy 査読

Hikaru Kawaguchi, Hiroyuki Imanaka, Koreyoshi Imamura, Naoyuki Ishida

Colloids and Surfaces A: Physicochemical and Engineering Aspects 627 127137 - 127137 2021年10月

Crystallization characteristics of amorphous trehalose dried from alcohol

Takanari Sekitoh, Takashi Okamoto, Akiho Fujioka, Tomohiko Yoshioka, Shinji Terui, Hiroyuki Imanaka, Naoyuki Ishida, Koreyoshi Imamura

Journal of Food Engineering 292 110325 - 110325 2021年3月

Spontaneous foaming during vacuum drying of polyvinylpyrrolidone- and sugar-alcohol mixtures and enhancement of water-dissolution of water insoluble drug

Olivier Tramis, Akiho Fujioka, Hiroyuki Imanaka, Naoyuki Ishida, Koreyoshi Imamura

Drying Technology 1 - 11 2020年9月

The Use of a Combination of a Sugar and Surfactant to Stabilize Au Nanoparticle Dispersion against Aggregation during Freeze-Drying

Hidetaka Yokota, Miki Kadowaki, Tsutashi Matsuura, Hiroyuki Imanaka, Naoyuki Ishida, Koreyoshi Imamura

Langmuir 36 ( 24 ) 6698 - 6705 2020年6月

Sole-amorphous-sugar-based solid dispersion of curcumin and the influence of formulation composition and heat treatment on the dissolution of curcumin

Takanari Sekitoh, Takashi Okamoto, Akiho Fujioka, Olivier Tramis, Koji Takeda, Tsutashi Matsuura, Hiroyuki Imanaka, Naoyuki Ishida, Koreyoshi Imamura

Drying Technology 39 ( 14 ) 1 - 10 2020年4月

Immobilization of surface non-affinitive protein onto a metal surface by an external electric field

Olivier Tramis, Ryosuke Iizuka, Hajime Nakao, Hiroyuki Imanaka, Naoyuki Ishida, Koreyoshi Imamura

Journal of Bioscience and Bioengineering 129 ( 3 ) 348 - 353 2020年3月

Picoliter enzyme reactor on a nanofluidic device exceeding the bulk reaction rate

Koki Yamamoto, Kyojiro Morikawa, Hiroyuki Imanaka, Koreyoshi Imamura, Takehiko Kitamori

The Analyst 145 ( 17 ) 5801 - 5807 2020年

Pico-liter protein digestion and separation using nanofluidic device

Kyojiro Morikawa, Koki Yamamoto, Hiroki Sano, Yutaka Kaoze, Hisashi Shimizu, Hiroyuki Imanaka, Koreyoshi Imamura, Takehiko Kitamori

MicroTAS 2020 - 24th International Conference on Miniaturized Systems for Chemistry and Life Sciences 1125 - 1126 2020年

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）出版者・発行元：Chemical and Biological Microsystems Society

The Needs of shotgun proteomics have been increasing in the field of biology and medicine for understanding biological systems. In study, protein sample with pL, which volume was same scale as single cell volume, was successfully digested and separated and detected by integrated device of pL enzyme reactor fL chromatography and UV-POPS detector. This nanofluidic device will greatly contribute to single cell shotgun proteomics.

Scopus

researchmap

Physical Stability of an Amorphous Sugar Matrix Dried From Methanol as an Amorphous Solid Dispersion Carrier and the Influence of Heat Treatment 査読

Journal of Pharmaceutical Sciences 108 ( 6 ) 2056 - 2062 2019年6月

Nanofluidic enzyme reactor exceeding limit of bulk reaction rate

Koki Yamamoto, Kyojiro Morikawa, Koreyoshi Imamura, Hiroyuki Imanaka, Takehiko Kitamori

23rd International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2019 113 - 114 2019年

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）出版者・発行元：Chemical and Biological Microsystems Society

We development a nanofluidic enzyme reactor exceeding the limitation of bulk enzyme reaction. The limit concentration of bulk trypsin solution is approximately 0.5 PM because self-digestion occurs over 0.5 PM solution, which complicates analysis of target proteins by digestion trypsin itself. Using extremely high surface/volume ration of nanospace, trypsin concentration, which indicates number of immobilized trypsin molecules on the nanochannel surface for liquid phase volume, exceed to bulk limit of concentration. As a result, 31 times higher concentration and 33 times faster enzyme reaction compared to bulk was realized. This reactor will be powerful tools which overcomes limitation in bulk and microfluidic method.

Scopus

researchmap

Adsorption characteristics of various proteins on a metal surface in the presence of an external electric potential 査読

Ei Ei Htwe, Yuhi Nakama, Yuko Yamamoto, Hiroshi Tanaka, Hiroyuki Imanaka, Naoyuki Ishida, Koreyoshi Imamura

Colloids and Surfaces B: Biointerfaces 166 262 - 268 2018年6月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Elsevier B.V.

The effect of the properties of a protein on its adsorption to a metal surface in the presence of external electric potential was investigated. Protein adsorption processes at different surface potentials were measured for fifteen types of proteins using an in-situ ellipsometry. The tested proteins were classified into three groups, based on the amount of protein that was adsorbed as a function of the surface potential: In First group of proteins, an increasing trend for the amount adsorbed with a more positive surface potential was found
The amount adsorbed of α-chymotrypsinogen A and ribonuclease A (Second group) were roughly constant and independent of the applied surface electric potentials
In Third group, the amount adsorbed decreased with increasing surface potential. This protein classification was correlated with the isoelectric points of the proteins (First group: ≤9.3
Second group: 9.3–10
Third group: &gt
10). Increasing the pH positively and negatively shifted the surface potentials, allowing ß-lactoglobulin (First group) and lysozyme (Third) to become adsorbed, respectively. The surface potential range for protein adsorption was also markedly shifted depending on the metal substrate type. These findings were interpreted based on the electrostatic interactions among the protein, surface hydroxyl groups, and the applied external electric field.

DOI： 10.1016/j.colsurfb.2018.03.035

Scopus

researchmap

Controlling the drying process in vacuum foam drying under low vacuum conditions by inducing foaming by needle stimulation of the solution 査読

Fumihiro Hidaka, Tomo Satoh, Akiho Fujioka, Koji Takeda, Hiroyuki Imanaka, Naoyuki Ishida, Koreyoshi Imamura

Drying Technology 36 2018年

　前のページ - 次のページ　

<今中 洋行>

論文 - 今中 洋行

<今中　洋行>

論文 - 今中　洋行