REVERSED-PHASE HPLC METHOD FOR THE ESTIMATION OF ACETAMINOPHEN, IBUPROFEN AND CHLORZOXAZONE IN FORMULATIONS

A simple, precise and rapid reversed-phase HPLC method was developed f or the simultaneous estimation of acetaminophen, ibuprofen and chlorzo xazone in formulations. The method was carried out on a Kromasil(R) C- 8 column using a mixture of 0.2% triethylamine:acetonitrile (adjusted to pH 3.2 using dilute orthophosphoric acid), and detection was carrie d out at 215 nm using ketoprofen as internal standard. All these drugs showed linearity in the range of 2-10 mu g ml(-1), and limits of quan tification was found to be 10, 50 and 20 ng ml(-1) for acetaminophen, ibuprofen and chlorzoxazone, respectively. (C) 1998 Elsevier Science B .V. All rights reserved.