DEVELOPMENT AND VALIDATION OF REVERSE PHASE HIGH PERFORMANCE LIQUID CHROMATOGRAPHY METHOD FOR SIMULTANEOUS ESTIMATION OF TAPENTADOL HYDROCHLORIDE AND LORNOXICAM IN SYNTHETIC MIXTURE

Abstract

A simple, precise, accurate and rapid reverse phase high performance liquid chromatographic method has been developed for the estimation of Tapentadol hydrochloride (TAP) and Lornoxicam (LOR) in combined synthetic mixture. The chromatographic separation was attained on reverse phase C₁₈ column (Phenomenex C₁₈, 250 mm × 4.6 mm, 5µm) as stationary phase with mobile phase comprising phosphate buffer (pH-3.5) : acetonitrile (65:35, v/v) with a flow rate of 1.0 ml/min. Quantification was achieved with Photo Diode Array detector at 275 nm.  The retention times of TAP and LOR were 2.24 min and 4.91 min respectively. The linearity of TAP and LOR were in the range of 5-30 ?g/ml and 2-12 ?g/ml respectively. The method was successfully applied to synthetic mixture because no chromatographic interferences from the mixture excipients were found. The method retained its accuracy and precision when the standard addition technique was applied.