Development and Validation of a Simultaneous RP-HPLC Method for the Estimation of Polmacoxib and Paracetamol in Combined Tablet Dosage Form

Background: Paracetamol and Polmacoxib are used in combination for the management of pain and inflammation associated with osteoarthritis. A simple and reliable analytical method is required for their simultaneous estimation in combined tablet dosage form. Objective: To develop and validate a simple, accurate, precise, and economical RP-HPLC method for the simultaneous estimation of Polmacoxib and Paracetamol in combined tablet dosage form. Methods: Chromatographic separation was carried out on a Hibar ODS C18 column. The mobile phase consisted of acetonitrile and 0.1% orthophosphoric acid in water (80:20 v/v), pH 4.5. The analysis was performed at a flow rate of 1.0 mL/min, with detection at 225 nm using a UV detector. The developed RP-HPLC method was validated according to ICH guidelines by evaluating specificity, linearity, precision, accuracy, limit of detection (LOD), and limit of quantification (LOQ). Results: The developed RP-HPLC method showed good chromatographic separation of Paracetamol and Polmacoxib, with retention times of 3.39 min and 5.92 min, respectively. The method exhibited excellent linearity over the concentration range of 325-975 µg/mL for Paracetamol and 2-6 µg/mL for Polmacoxib, with correlation coefficients of approximately 0.999. Accuracy studies demonstrated recovery values within the acceptable range of 98-102%, while precision studies showed %RSD values below 2%, indicating good reproducibility. The method was found to be robust and sensitive, with satisfactory LOD and LOQ values, and was successfully applied to the assay of marketed formulations, producing results within acceptable limits. Conclusion: A simple, rapid, accurate, and precise RP-HPLC method was successfully developed and validated for the simultaneous estimation of Paracetamol and Polmacoxib in combined tablet dosage form. The proposed method is suitable for routine quality control analysis.