Method Development and Validation of Carisoprodol and its Impurities by Ultra Violet-High Performance Liquid Chromatography

Ultraviolet-h igh performance liquid chromatographic (UV-HPLC) method was developed for the quantitation of carisoprodol and its impurities viz 2-methyl-2-propylpropane-1, 3-diyl d icarbamate (impurity-D) and N-isopropyl -2-methyl-2-propyl-3-hydroxy propyl carbamate (impurity-B) in active pharmaceutical ingredient. Validation of the method showed excellent sensitivity, selectivity, accuracy, precision and ruggedness. Efficient chromatographic separation was achieved on a Zorbax eclipse XDB C (8) 250 mm X 4.6 mm id, 5μm , stationary phase in gradient mode and quantitation by ultraviolet wavelength detection. The method was validated as per International Conference of Harmonization (ICH) guidelines in terms of Quantitation limit (QL), Detection limit (DL), Linearity, Precision, Accuracy and Specificity. The QL and DL values for impurity-B were found to be 0.015% and 0.008% and for that of impurity-D were found to be 0.26% and 0.13%respectively, with respect to sample concentration. The method was linear within the range of QL to 200% for the two impurities. Thus, the newly developed method was found to be accurate, efficient and stable. The characterization of these impurities was carried out for the confirmation of respective structures using nuclear magnetic resonance spectroscopy (NMR).