Development and validation of a new high-performance liquid chromatographic estimation method of meloxicam in biological samples

A simple, HPLC method was developed to estimate meloxicam (COX-2 inhibitor) using piroxicam as the internal standard. The mobile phase containing methanol, acetonitrile and an aqueous solution of diammonium hydrogenorthophosphate (50 mM) in the ratio of 4:1:5 was pumped at the rate 1 ml/min. Lichrocart RP-18 (125x4 mm) was used as an analytical column and the analytes were detected at 364 nm using a UV detector. Acidified plasma samples were extracted with chloroform, evaporated to dryness, reconstituted in the mobile phase and then a volume of 10 mu l of the prepared sample was injected in the column. The retention time of meloxicam and piroxicam was found to be 2.7 and 1.9, respectively. This method showed an accuracy of 102.3% at 0.52 mu g/ml and was capable of detecting a minimum concentration of 0.029 mu g/ml meloxicam from biological samples. The analytical method was successfully utilized for estimating meloxicam in biological samples. (C) 2000 Elsevier Science B.V. All rights reserved.