Lin S Y
Department of Medical Research, Veterans General Hospital-Taipei, Taipei, Republic of China.
J Pharm Sci. 1992 Jun;81(6):572-6. doi: 10.1002/jps.2600810622.
A new polymorphic crystal form of indomethacin was precipitated from an aqueous solution of indomethacin and beta-cyclodextrin by titration with a 0.5 N HCl aqueous solution. Three polymorphs (alpha, beta, and gamma forms) and a new crystal form were differentiated with thermal analysis, infrared spectroscopy, powder X-ray diffractometry, thin-layer chromatography, elemental analysis, and Fourier transform infrared (FTIR) spectroscopy with a newly developed FTIR microscope equipped with a thermal analyzer. The new crystal polymorph of indomethacin exhibited endo- and exothermic peaks near 102.8 and 104.1 degrees C, respectively, because of phase transitions without weight loss, followed by two additional endothermic peaks at 151 and 158.9 degrees C, because of fusion. The differential scanning calorimetry-FTIR system can be used to examine the correlation between structural change of C = O stretching bands of this new polymorph and its thermal response. The new crystal form contained some gamma-form crystals, determined with an FTIR microscope equipped with a mapping option. Solid-state carbon-13 nuclear magnetic resonance spectra of the polymorphs of indomethacin were also examined.
通过用0.5N盐酸水溶液滴定，从吲哚美辛和β-环糊精的水溶液中沉淀出一种新的吲哚美辛多晶型晶体。通过热分析、红外光谱、粉末X射线衍射、薄层色谱、元素分析以及配备热分析仪的新开发的傅里叶变换红外（FTIR）显微镜进行的FTIR光谱，区分了三种多晶型物（α、β和γ型）和一种新的晶体形式。吲哚美辛的新晶体多晶型物分别在102.8和104.1摄氏度附近表现出吸热和放热峰，这是由于无相变失重的相变引起的，随后在151和158.9摄氏度出现另外两个吸热峰，这是由于熔融引起的。差示扫描量热法 - FTIR系统可用于研究这种新多晶型物的C = O伸缩带的结构变化与其热响应之间的相关性。用配备绘图选项的FTIR显微镜确定，新晶体形式包含一些γ型晶体。还对吲哚美辛多晶型物的固态碳 - 13核磁共振光谱进行了研究。
