analytical study on stability of Indomethacin

Abstract

In this study, the stability of indomethacin was investigated in different physical and chemical conditions using various analytical techniques. Ultra-violet spectrophotometric studies of the drug in several solvents and at a wide range of pHs were carried out. Isobestic points in the UV spectra were located. Both solid and liquid indomethacin were exposed to direct sun rays. Increasing the temperature as high as 120 °C. Applying various analytical techniques, HPLC was found to be the most sensitive to detect the decomposition of the drug. Indomethacin was subjected to alkaline hydrolysis that resulted in the production of two different compounds. These compounds were isolated and identified by various analytical techniques, such as TLC, GC/MS, UV, and IR spectrophotometric methods. The identification was supported by the study of the kinetic behaviour and the derivatization of the analyte drug. The products of the alkaline hydrolysis were identified as p-chlorobenzoic acid and 2-methyl-5-methoxy-indol-3-ylacetic acid.