Polymorphism in nimodipine raw materials: development and validation of a quantitative method through differential scanning calorimetry.
Due to the physical-chemical and therapeutic impacts of polymorphism, its monitoring in raw materials is necessary. The purpose of this study was to develop and validate a quantitative method to determine the polymorphic content of nimodipine (NMP) raw materials based on differential scanning calorimetry (DSC). The polymorphs required for the development of the method were characterized through DSC, X-ray powder diffraction (XRPD) and Raman spectroscopy and their polymorphic identity was confirmed. The developed method was found to be linear, robust, precise, accurate and specific. Three different samples obtained from distinct suppliers (NMP 1, NMP 2 and NMP 3) were firstly characterized through XRPD and DSC as polymorphic mixtures. The determination of their polymorphic identity revealed that all samples presented the Modification I (Mod I) or metastable form in greatest proportion. Since the commercial polymorph is Mod I, the polymorphic characteristic of the samples analyzed needs to be investigated. Thus, the proposed method provides a useful tool for the monitoring of the polymorphic content of NMP raw materials.
Post Graduate Program in Pharmacy, Federal University of Santa Catarina, Florianopolis, SC 88040-970, Brazil. manoelakr@hotmail.com
Manoela Klüppel
MK
Riekes
Rafael Nicolay
RN
Pereira
Gabriela Schneider
GS
Rauber
Silvia Lucia
SL
Cuffini
Carlos Eduardo Maduro
CE
de Campos
Marcos Antonio Segatto
MA
Silva
Hellen Karine
HK
Stulzer
D000704:Analysis of Variance; D002121:Calcium Channel Blockers / Q000737:chemistry*; D002138:Calibration; D002152:Calorimetry, Differential Scanning / Q000592:standards; D003460:Crystallization; D018360:Crystallography, X-Ray; D057230:Limit of Detection; D016014:Linear Models; D009553:Nimodipine / Q000737:chemistry*; D033362:Powder Diffraction; D015203:Reproducibility of Results; D013059:Spectrum Analysis, Raman
D002121:Calcium Channel Blockers; D009553:Nimodipine