Study of doxofylline and its degradation products in bulk drug by a newly developed stability-indicating HPLC method.

The purpose of this work was to study the stability behavior of doxofylline under different stress conditions and to develop a sensitive stability-indicating HPLC assay method. The stress conditions applied included heat, moisture, acid-base hydrolysis, oxidation, and UV light. The drug was particularly labile under oxidative and thermal stress conditions, with 58.

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.