Extractive Spectrophotometric Method for the Determination of Metaxalone in Bulk and its Pharmaceutical Formulation

Metaxalone, a muscle relaxant used to relax muscles and relieve pain caused by strains, sprains and other musculoskeletal conditions a simple, sensitive, rapid and cost effective extraction spectrophotometric method was described for the assay of Metaxalone in bulk samples and pharmaceutical formulations. The method was based on the formation of chloroform soluble ion-pair complexes of Bromophenol blue with Metaxalone, formed pink colored chromogen in a phosphate buffer of pH 4 with absorbance maximum at 630nm. The developed spectrophotometric method was validated in accordance with ICH guidelines. Linearity of the method was found to be 10–50μg/ml and obeyed Beer's law. The LOD and LOQ were found to be 0.6757μg/ml and2.389μg/ml respectively. The results of analysis for the method have been validated statistically and by recovery studies. The proposed method was simple, sensitive, accurate and suitable for quality control applications.