Enhancement of Stability profile of Aspirin through Cocrystallization Technique

Abstract

Cocrystallization process is a well-known technique for altering the pharmaceutical properties of drugs without modifying their actual pharmacological actions. Availability of a number of potential coformers make this technique more useful for implementation in pharmaceutical research area on newer and older API’s having pharmaceutical issues like poor solubility, stability profiles etc. Aspirin is a long-known antipyretic and anti-inflammatory drug belonging to BCS Class II having poor aqueous solubility. This API undergoes hydrolysis at higher temperature and in humid environment with the resultant degradation products being salicylic acid and acetic acid. Cocrystalization technique could be useful for improving its stability profile as the physicochemical properties of drugs get modified by their cocrystallization with coformers having better thermal stability as well higher solubility profile than API’s. In this study, aspirin and benzoic acid have been cocrystallized in a fixed stochiometric ratio (1:2) for improving its stability issues. Differential Scanning Calorimetry (DSC), Infra-Red spectroscopy technique (FTIR) and X-ray Diffraction (XRD) technique were used for analysis of cocrystals. Dissolution study was performed which revealed an improved dissolution profile of cocrystals compared to pure drug aspirin. Accelerated stability study was performed as per ICH guidelines for 6 months and stability profile of drug and cocrystals were compared by using HPLC technique, which exhibited a better stability profile of cocrystals compared to pure drug.