Abstract

A simple, fast, precise and accurate RP-HPLC method was developed for the simultaneous estimation of valdecoxib and tizanidine hydrochloride in tablet formulations. The separation was achieved by C18 Intersil column and acetonitrile: 0.02 M phosphate buffer (pH 3.5) (60:40 v/v) as mobile phase, at a flow rate of 1.5 ml/min. Detection was carried out at 240 nm. The retention time of valdecoxib and tizanidine hydrochloride was found to be 4.21 and 2.16 min respectively. The validation of the proposed method was also carried out for linearity, accuracy and precision. The linear dynamic range for valdecoxib and tizanidine hydrochloride was 0-100 µg/ml and 0-20 µg/ml respectively. The mean percentage recoveries obtained for valdecoxib and tizanidine hydrochloride were 99.10 and 100.19% respectively. The developed method was found to be accurate, precise, selective and rapid, and it can also be used for routine quality control analysis of these drugs in combination tablets.