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Updated: Oct 4, 2026

Preparation of Functional Silica Using a Bioinspired Method
Published on: August 1, 2018
Stability of amorphous indomethacin compounded with silica
T Watanabe1, N Wakiyama, F Usui
1Product Development Laboratories, Sankyo Co., Ltd., 1-2-58 Hiromachi, Shinagawa-ku, Tokyo 140-8710, Japan. watatm@shina.sankyo.co.jp
Abstract:
The stability of indomethacin (IM) compounded with SiO(2) either by co-grinding or by melt-quenching was examined by recrystallization kinetics under the conditions 30 degrees C and 11% relative humidity. A decrease of the recrystallization rate with and without an appreciable induction period was observed in both compounds. Higher stability of amorphous IM compounded with SiO(2) was attained by prolonged co-grinding than by melt-quenching. This was explained by the stronger chemical interaction at the interface between IM and SiO(2) by co-grinding, as revealed by (29)Si and (13)C solid state NMR. Incomplete co-grinding with the rest of the crystalline state, however, made the amorphous state appreciably unstable, since the remaining crystallites serve as seeds for recrystallization.
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