RP-HPLC Method Development and Validation of Etodolac and Paracetamol in Combined Dosage Form

A simple, specific, accurate and precise reverse phase high pressure liquid chromatographic method has been developed for the simultaneous determination of Etodolac and Paracetamol from tablets. Stationary phase used was C18 column (symmetry C₁₈, 250 mm x 4.5 mm). The sample was analyzed using acetonitrile: water in the ratio of 50:50 (pH adjusted to 5.8 with ortho phosphoric acid) as a mobile phase at a flow rate of 1.0 ml/min and detection was done at 232nm. The described method was linear over a concentration range of 2-14 μg/ml (r² =0.999793 and0.999708) for Etodolac and Paracetamol respectively. The retention time for Etodolac and Paracetamol was found to be 1.932 and 2.456 min respectively, and recoveries from tablet were between 98.2%w/w and 101.2 %w/w. The limit of quantification (LOQ) for Etodolac and Paracetamol were found to be 0.15 and 0.04 μg/ml respectively The system suitability parameters were within the limit. The method developed was validated according to ICH guidelines which prove that the method was precise, accurate and can be used for routine determination of Etodolac and Paracetamol in bulk drug and its pharmaceutical dosage forms.