Optimization and establishment of a validated stability-indicating HPLC method for study of the stress degradation behavior of metoprolol succinate.

A stability-indicating HPLC method has been established for analysis of metoprolol succinate in the presence of products generated in a stress degradation study. The drug was subjected to stress conditions of hydrolysis, oxidation, photolysis, and thermal decomposition. Extensive degradation was found to occur in an alkaline medium and under thermal stress. Minimum degradation was observed in an acidic medium and under photolytic and oxidative stress. Successful separation of the drug from its degradation products formed under stress conditions was achieved on a C18 column using sodium dihydrogen phosphate buffer-acetonitrile (70 + 30) mobile phase. The flow rate was 1 mL/min, and the detection wavelength was 274 nm. The method was validated for linearity, range, precision, accuracy, LOQ, and LOD. Because the method effectively separates the drugs from their degradation products, it can be used as a stability-indicating method.