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Revised method for preparation of simulated body fluid for assessment of the apatite-forming ability of bioactive materials: proposal of mixing two stock solutions 査読有り Open Access

14 巻頁： 38660 - 38667 2024年12月

Revised method for preparation of simulated body fluid for assessment of the apatite-forming ability of bioactive materials: proposal of mixing two stock solutions. 査読有り国際誌 Open Access

Wanyu Dong, Yuko Matsukawa, Yanglifu Long, Yoshinao Hayashi, Jin Nakamura, Kazumasa Suzuki, Chikara Ohtsuki

RSC advances 14 巻 ( 52 ) 頁： 38660 - 38667 2024年12月

Apatite Formation on α-Tricalcium Phosphate Modified with Bioresponsive Ceramics in Simulated Body Fluid Containing Alkaline Phosphatase. 査読有り国際誌 Open Access

Taishi Yokoi, Shinji Tomita, Jin Nakamura, Ayae Sugawara-Narutaki, Yuko Matsukawa, Masakazu Kawashita, Chikara Ohtsuki

Biomimetics (Basel, Switzerland) 9 巻 ( 8 ) 頁： 502 2024年8月

担当区分：最終著者記述言語：英語掲載種別：研究論文（学術雑誌）

Bioresponsive ceramics, a new concept in ceramic biomaterials, respond to biological molecules or environments, as exemplified by salts composed of calcium ions and phosphate esters (SCPEs). SCPEs have been shown to form apatite in simulated body fluid (SBF) containing alkaline phosphatase (ALP). Thus, surface modification with SCPEs is expected to improve the apatite-forming ability of a material. In this study, we modified the surface of α-tricalcium phosphate (α-TCP) using methyl, butyl, or dodecyl phosphate to form SCPEs and investigated their apatite formation in SBF and SBF containing ALP. Although apatite did not form on the surface of the unmodified α-TCP in SBF, apatite formation was observed following surface modification with methyl or butyl phosphate. When ALP was present in SBF, apatite formation was especially remarkable on α-TCP modified with butyl phosphate. These SCPEs accelerated apatite formation by releasing calcium ions through dissolution and supplying inorganic phosphate ions, with the latter process only occurring in SBF containing ALP. Notably, no apatite formation occurred on α-TCP modified with dodecyl phosphate, likely because of the low solubility of the resulting calcium dodecyl phosphate/calcium phosphate composites. This new method of using SCPEs is anticipated to contribute to the development of novel ceramic biomaterials.

DOI： 10.3390/biomimetics9080502

Open Access

PubMed

Loading of antibiotic molecules into organically modified layered calcium silicate 査読有り国際誌 Open Access

Nakamura, J; Kato, H; Miyazaki, T; Ohtsuki, C

JOURNAL OF ASIAN CERAMIC SOCIETIES 12 巻 ( 3 ) 頁： 227 - 233 2024年7月

In Situ and Ex Situ Studies of Ring-Like Assembly of Silica Nanoparticles in the Presence of Poly(propylene oxide)-Poly(ethylene oxide) Block Copolymers. 査読有り国際誌

Rintaro Takahashi, Kazuki Yamamoto, Ryo Sugahara, Ryusuke Otake, Keisuke Hayashi, Jin Nakamura, Chikara Ohtsuki, Sadahito Aoshima, Ayae Sugawara-Narutaki

Langmuir : the ACS journal of surfaces and colloids 39 巻 ( 32 ) 頁： 11379 - 11387 2023年8月

記述言語：英語掲載種別：研究論文（学術雑誌）

Block copolymer-mediated self-assembly of colloidal nanoparticles has attracted great attention for fabricating various nanoparticle arrays. We have previously shown that silica nanoparticles (SNPs) assemble into ring-like nanostructures in the presence of temperature-responsive block copolymers poly[(2-ethoxyethyl vinyl ether)-block-(2-methoxyethyl vinyl ether)] (PEOVE-PMOVE) in an aqueous phase. The ring-like nanostructures formed within an aggregate of PEOVE-PMOVE when the temperature was increased to 45 °C, at which the polymer is amphiphilic. Herein, we report that SNPs assemble into ring-like nanostructures even with a different temperature-responsive, amphiphilic block copolymer poly(propylene oxide)-block-poly(ethylene oxide) (PPO-PEO) at 45 °C. Field-emission scanning electron microscopy for SNP assemblies that were spin-coated on a substrate indicated that SNP first assembled into chain-like nanostructures and then bent into closed loops over several days. In contrast, in situ small-angle X-ray diffraction measurements revealed the formation of SNP nanorings within 75 s at 45 °C in the liquid phase. These results indicated that ring-like assembly of SNPs occurs quickly in the liquid phase, but the slow formation of Si-O-Si bonds between SNPs leads to their structure being destroyed by spin-coating. Intriguingly, SNPs with a diameter of 15 nm form a well-defined nanoring structure, with five SNPs located at the vertex points of a regular pentagon. Additionally, small-angle neutron scattering, where the contrast of the solvent (a mixture of H2O and D2O) matches that of SNPs, clarified that SNPs are contained within the spherical micelle formed from PPO-PEO. This work offers a facile and versatile approach to preparing ring-like arrays from inorganic colloidal nanoparticles, leading to applications including sensing, catalysis, and nanoelectronics.

DOI： 10.1021/acs.langmuir.3c01210

PubMed

Biological properties of self-assembled nanofibers of elastin-like block polypeptides for tissue-engineered vascular grafts: platelet inhibition, endothelial cell activation and smooth muscle cell maintenance 査読有り国際誌 Open Access

Natsume, K; Nakamura, J; Sato, K; Ohtsuki, C; Sugawara-Narutaki, A

REGENERATIVE BIOMATERIALS 10 巻 ( rbac111 ) 頁： rbac111 2023年1月

Transformation behaviour of salts composed of calcium ions and phosphate esters with different linear alkyl chain structures in a simulated body fluid modified with alkaline phosphatase 査読有り国際誌 Open Access

Yokoi, T; Mio, A; Nakamura, J; Sugawara-Narutaki, A; Kawashita, M; Ohtsuki, C

SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS 23 巻 ( 1 ) 頁： 341 - 351 2022年12月

Organic modification of layered zirconium phosphate/phosphonate for controlled release of therapeutic inorganic ions 査読有り国際誌 Open Access

Nakamura, J; Ito, R; Kozaki, R; Sugawara-Narutaki, A; Ohtsuki, C

SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS 22 巻 ( 1 ) 頁： 1000 - 1012 2021年12月

Selective adsorption of dyes on TiO<sub>2</sub>-modified hydroxyapatite photocatalysts morphologically controlled by solvothermal synthesis 査読有り

Goto, T; Cho, SH; Ohtsuki, C; Sekino, T

JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING 9 巻 ( 4 ) 頁： 105738 - 105738 2021年8月

Thixotropic Hydrogels Composed of Self-Assembled Nanofibers of Double-Hydrophobic Elastin-Like Block Polypeptides 査読有り国際誌 Open Access

Sugioka, Y; Nakamura, J; Ohtsuki, C; Sugawara-Narutaki, A

INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES 22 巻 ( 8 ) 頁： 4104 2021年4月

Incorporation of tetracarboxylate ions into octacalcium phosphate for the development of next-generation biofriendly materials 査読有り国際誌 Open Access

Yokoi, T; Goto, T; Hara, M; Sekino, T; Seki, T; Kamitakahara, M; Ohtsuki, C; Kitaoka, S; Takahashi, S; Kawashita, M

COMMUNICATIONS CHEMISTRY 4 巻 ( 1 ) 頁： 4 - 4 2021年1月

Preparation of layered calcium silicate organically modified with two types of functional groups for varying chemical stability 査読有り国際誌 Open Access

Nakamura, J; Suzuki, Y; Narukawa, R; Sugawara-Narutaki, A; Ohtsuki, C

JOURNAL OF ASIAN CERAMIC SOCIETIES 9 巻 ( 1 ) 頁： 90 - 100 2021年1月

Behaviour of calcium phosphate ester salts in a simulated body fluid modified with alkaline phosphatase: a new concept of ceramic biomaterials 査読有り国際誌 Open Access

Yokoi, T; Ujiyama, T; Nakamura, J; Kawashita, M; Ohtsuki, C

MATERIALS ADVANCES 1 巻 ( 9 ) 頁： 3215 - 3220 2020年12月

Human stem cell response to layered zirconium phosphate 査読有り

Jin Nakamura, Kanta Endo, Ayae Sugawara-Narutaki, Chikara Ohtsuki(DOI: 10.1039/d0ra04924g)

RSC Advances 10 巻頁： 36051-36057 2020年9月

Tearable and Fillable Composite Sponges Capable of Heat Generation and Drug Release in Response to Alternating Magnetic Field 査読有り

Koichiro Hayashi, Atsuto Tokuda, Jin Nakamura, Ayae Sugawara-Narutaki, Chikara Ohtsuki

Materials 13 巻 ( 16 ) 頁： 3637 2020年8月

Hydroxyapatite Formation from Octacalcium Phosphate and Its Related Compounds: A Discussion of the Transformation Mechanism 査読有り Open Access

Yokoi, T; Goto, T; Kato, T; Takahashi, S; Nakamura, J; Sekino, T; Ohtsuki, C; Kawashita, M

BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 93 巻 ( 5 ) 頁： 701 - 707 2020年5月

Rheology of Dispersions of High-Aspect-Ratio Nanofibers Assembled from Elastin-Like Double-Hydrophobic Polypeptides 査読有り国際誌 Open Access

Sugawara-Narutaki, A; Yasunaga, S; Sugioka, Y; Le, DHT; Kitamura, I; Nakamura, J; Ohtsuki, C

INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES 20 巻 ( 24 ) 2019年12月

Ring-Like Assembly of Silica Nanospheres in the Presence of Amphiphilic Block Copolymer: Effects of Particle Size 査読有り国際誌

Atsumi, C; Araoka, S; Landenberger, KB; Kanazawa, A; Nakamura, J; Ohtsuki, C; Aoshima, S; Sugawara-Narutaki, A

LANGMUIR 34 巻 ( 26 ) 頁： 7751 - 7758 2018年7月

Apatite coating on dendrimer-modified buckypaper and the formation of nanoapatite on MWCNTs 査読有り

Tomoyuki Tajima, Tomoaki Tanaka, Hideaki Miyake, Ill Yong Kim, Chikara Ohtsuki and Yutaka Takaguchi

Polymer Journal 2018年5月

Introduction of alkylammonium into calcium silicate hydrate towards application in development of novel biomaterial

Jin Nakamura, Ryosuke Narukawa, Ayae Sugawara-Narutaki, Chikara Ohtsuki

Funtai Oyobi Fummatsu Yakin/Journal of the Japan Society of Powder and Powder Metallurgy 65 巻 ( 6 ) 頁： 325 - 327 2018年

記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：Journal of the Japan Society of Powder and Powder Metallurgy

Human body contains trace inorganic elements that play important roles in the regulation of vital reactions. Biomaterials releasing the trace inorganic elements are suggested to be beneficial for tissue reconstruction remedies. The authors focused on inorganic layered compounds that give drug-releasing system tailored by assembling nanosheet-like crystals of the compounds with inserting ions and macromolecules which promote tissue regeneration. In the present study, calcium silicate hydrate (C-S-H) was selected as the framework, and its preparation conditions via precipitation method were explored. Moreover, the incorporation behaviors of alkylammonium molecules into the C-S-H were evaluated by their simultaneous addition during the method. Agglomerates of nanosheet-like C-S-H were precipitated by introducing calcium nitrate aqueous solution into equimolar concentration of sodium silicate aqueous solution in a controlled manner. By soaking C-S-H into simulated body fluid, which mimicked the inorganic elemental composition of human blood plasma, bone-like apatite was precipitated on its surface. The incorporation of tetrabuthylammonium cations (TBA+) were conducted by the addition of its hydroxide into sodium silicate aqueous solution during the preparation. XRD pattern of the sample showed the broadening of a peak, attributed to the interlayer distances in a C-S-H crystal. These results suggested the introduction of TBA+ in the C-S-H.

DOI： 10.2497/jjspm.65.325

Scopus

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