A Validated RP-HPLC Method for Simultaneous Estimation of Acetaminophen and Methocarbamol in Tablets

Abstract

A rapid, sensitive and specific RP-HPLC method involving UV detection was developed and validated for simultaneous determination and quantification of acetaminophen and methocarbamol. Chromatography was carried out on a pre-packed develosil-C18 (5 μm 25 × 0.46 cm) column using water: methanol:glacial acetic acid (60:40:1.5) as mobile phase at a flow rate of 1 mL min^-1 and effluent were monitored at 273 nm. The assay was linear over the concentration range of 62.5-500 μg mL^-1 and 50-400 μg mL^-1 for acetaminophen and methocarbamol, respectively. The per cent recovery was ranging from 99.98-100.03, 99.75-100.07 % for acetaminophen and methocarbamol, respectively with an intra day, inter-day precision RSD of 0.678, 0.487 and 0.607, 0.563 for acetaminophen and methocarbamol. The method does require only 7 min as run time for analysis which prove the adoptability of the method for the routine quality control of these drugs.