基于红外和拉曼光谱技术研究拉米夫定药物多晶型及其晶型变化现象

Investigation of Polymorphism and Polymorphic Transition of Lamivudine Based on FT-IR and Raman Spectroscopical Techniques

本文利用傅里叶变换红外(FT-IR)和拉曼(Raman)光谱方法在室温下对拉米夫定药物的水合与无水晶型进行表征,并对两种晶型的分子振动模式进行归属。结果表明两种晶型在分子振动模式上有着显著不同。此外,使用Raman光谱技术研究其水合晶型在加热过程中因失水而导致的晶型转变的动态特性,并选取拉曼光谱中峰面积随加热时间变化的785和798cm-1处特征峰,建立单指数数据拟合模型。由结果可知,在水合晶型加热转变过程中,水合晶型特征峰的消失与无水晶型特征峰出现的速率一致。该结果为多晶型药物的质量监控及建立药物晶型转变模型的研究提供了理论依据。

In this study, lamivudine, which has hydrated and anhydrous polymorphs,is charac- terized by Fourier transform infrared （FT-IR） and Raman spectroscopic techniques at room temperature. The vibrational modes of different motions are obtained by the assignment of the spectra of lamivudine hydrate and anhydrous lamivudine. The results indicate that there is obvious difference within the molecular vibrational modes of the two polymorphs. In addi- tion,the process of polymorphic transition of lamivudine hydrate due to dehydration is inves- tigated by Raman spectrum. The changes of characteristic peak areas at 785 and 798 cm^-1 with heating time are fitted with single exponential function. It indicates that the rate of lamivudine hydrate characteristic peak disappeared and anhydrous lamivudine peak appeared is consistent during dehydration transition process of lamivudine hydrate. The results provide important theoretical benchmark for quality monitoring of the polymorphic drugs and establishing the corresponding model of polymorphic transition in the pharmaceutical field.