Development and Validation of a Stability Indicating RP-HPLC Method for Simultaneous Estimation of Tapentadol and Paracetamol in Bulk and Tablet Dosage Form

A simple, selective, and sensitive stability-indicating Reverse phase high performance liquid chromatographic method has been developed and validated for the simultaneous estimation of Paracetamol and Tapentadol in bulk and tablet dosage form. The separation was achieved on a Thermo Hypersil BDS C18, 250 mm × 4.6 mm and 5 μm column with detection of 215nm at 40°c using an isocratic mobile phase mixture of Sodium di hydrogen ortho phosphate (0.1M, pH adjusted to 7 with ortho phosphoric acid) and methanol (60:40 v/v) at flow rate of 0.8 ml/min. The retention times for Paracetamol and Tapentadol were found to be 2.39min and 4.6min respectively with good resolution of 11.32. The method was validated for precision, linearity, accuracy, specificity, LOD, LOQ and Robustness. The calibration curves for Paracetamol and Tapentadol were linear in the concentration range of 325–975 μg/mL, and 50–150 μg/mL respectively. Recoveries for Paracetamol and Tapentadol were found to be in the range of 99% -100% and 100%-102% respectively. Forced degradation studies were performed using acid, base, water and hydrogen peroxide. No interference of the degradation products was detected. As the method is simple, accurate, precise the proposed method can be used for simultaneous estimation of these two drugs in their tablet dosage forms.