ABSTRACT

A Reverse Phase High Performance Liquid Chromatographic method was developed and validated for the simultaneous estimation of lornoxicam and tolperisone hydrochloride in bulk drug and its combined dosage form. Chromatographic separation was carried out isocratically by reverse phase water enable C₁₈ column (250 mm × 4.6 mm, 5.0 μ) using methanol: acetonitrile: water in ratio of 60:30:10 (V/V/V, pH adjusted to 3.0 with orthophosphoric acid) as a mobile phase at a flow rate of 1 mg min^-1 and UV visible detection at wavelength of 285 nm. The retention times for tolperisone hydrochloride and lornoxicam were found to be 2.551 and 3.787 min, respectively. The described method was linear over concentration range 30 – 135 mg mL^-1 and 1.6 – 7.2 μg mL^-1 with correlation coefficients 0.999 and 0.999 for tolperisone hydrochloride and lornoxicam, respectively. The intra day and inter day precisions were found to be less than 2 %, showing high precision of method. The accuracy of the methods was assessed by recovery studies and was found to be 98.95-101.65 % and 99.36-101.57 % for tolperisone hydrochloride and lornoxicam, respectively. Percentage assay of marketed formulation (tolperisone hydrochloride 150 mg and lornoxicam 8 mg) was found to be 99.94 % and 101.26 % for tolperisone hydrochloride and lornoxicam, respectively. The developed method was further validated as per ICH (Q2)R1 guidelines. The developed method can further be employed for routine quality control analysis of lornoxicam and tolperisone hydrochloride in its combined dosage forms.