Quantification and In Silico Toxicity Assessment of Nimesulide and its Related Substances

Availability of analytical method which is compatible with both Ultra high performance liquid chromatography (UHPLC) and Liquid chromatography mass spectrometry to identify and quantify the impurities in pharmaceutical products is an advantage for drug product development; such analytical method was developed for Nimesulide using a fused core column. Ammonium acetate and methanol were used as mobile phase in the gradient elution at a detection wavelength 230 nm. Quality-by-design principles helped in identifying the critical method development parameters and design space. Limit of detection and the limit of quantification are 0.025 and 0.075%, respectively. Precision of the method is <0.4% RSD and correlation coefficient is >0.999 for Nimesulide and all related substances. Accuracy of Nimesulide ranged from 99.3 to 100.4% at assay concentration. Application of this method in stability analysis has been demonstrated by analyzing stressed samples. The method was validated for specificity, linearity, accuracy, precision and robustness in compliance with International Conference on Harmonization (ICH) Q2(R1). This is the first reported UHPLC method for the estimation of Nimesulide and its related substances. According to ICH M7 guidelines, all impurities were assessed for genotoxicity, LD50, skin sensitization, irritation potential and carcinogenicity using Derek and TOPKAT software. Combined knowledge of analytical and toxicology assessment will help in developing safe and quality product.