The crystallization process of noncrystalline indomethacin (IMC) obtained by the grinding and by the fusion method was analyzed by a kinetic method. The noncrystalline samples of IMC were the a form ground for 10 h at 4°C (GNCα), the γ form ground for 10h at 4°C (GNCγ) and the fused solid (NC). Ten kinetic models were employed, and crystallinity was determined by X-ray diffractometry. Data obtained were used to determine the thermodynamic parameters and crystallization mechanism. Under isothermal conditions GNCa crystallized in both the α and γ forms simultaneously. The GNCγ and NC crystallized in the γ form, and the results of the Hancock-Sharp method suggested that both crystallizations occurred by a two-dimensional phase boundary reaction: the activation energies (E) were estimated to be 24.1 and 27.2 kcal/mol. The crystallization rate of GNCγ was about 60 times faster than that of NC, and therefore NC was a very stable noncrystalline solid. These results suggest that there are several kinds of noncrystalline solids. © 1988, The Pharmaceutical Society of Japan. All rights reserved.
CITATION STYLE
Otsuka, M., & Kaneniwa, N. (1988). A kinetic study of the crystallization process of noncrystalline indomethacin under isothermal conditions1). Chemical and Pharmaceutical Bulletin, 36(10), 4026–4032. https://doi.org/10.1248/cpb.36.4026
Mendeley helps you to discover research relevant for your work.