Analytical Separation and Characterisation of Degradation Products and the Development and Validation of a Stability-Indicating Method for the Estimation of Impurities in Montelukast Oral Dosage Formulation
A short selective, precise, accurate and sensitive stability-indicating gradient LC-MS/MSn method was developed for the quantitative determination of process-related impurities and degradation products of Montelukast in pharmaceutical oral dosage formulations. During the stress study, the degradation products of Montelukast were well-resolved from Montelukast and its impurities and the mass balances were found to be satisfactory in all the stress conditions, thus proving the stability-indicating capability of the method. The developed method was validated as per ICH guidelines with respect to specificity, linearity, limit of detection and quantification, accuracy, precision, ruggedness, and robustness. During the stability analysis of the drug product, one unknown impurity was detected by the above stability-indicating method. The flow rate was 0.5 ml/min and effluent was monitored at 226nm. Retention time was found to be 7.836±0.012 min. The LOD and LOQ values were found to be 0.2099 (μg/ml) and 0.6362 (μg/ml) respectively.