Raman Spectroscopy Analysis and Dissolution Experiment of Nimodipine in Two Crystal Forms / 医药导报

ABSTRACT

Objective To establish an innovative methods for the identification of nimodipine polymorphs. Methods Nimodipine of two crystal forms were prepared by rapid solvent removal and identified by powder X-ray diffraction, infrared spectroscopy and Raman spectroscopy.The dissolution study of the powder samples were carried out in six different mediums. Results Powder X-ray diffraction patterns of crystal form A and B could be used for the identification of crystal forms of nimodipine.Crystal form B has characteristic diffraction peaks at 2θ=5° and 2θ=13° in the pattern,while crystal form A has characteristic diffraction peaks at 2θ=27° distinguishing two crystal forms effectively. Raman spectrum could be used to identify the crystal forms.Compared with Raman spectra of crystal form B, there exists characteristic scattering peak at 500 cm-1 in crystal form A. According to the position and intensity of the peaks of crystal form A and B, it could distinguish two crystal types effectively.The results of dissolution tests showed that the solubility of crystal form A is better than crystal form B. Conclusion Various analysis techniques in different principle were used in the research, such as Powder X-ray diffraction, Infrared spectroscopy and Raman Spectroscopy etc.Crystal forms were confirmed in several aspects according to the properties of different crystal form, and the solubility of crystal form A is better than crystal form B.