Selective and rapid liquid chromatography-mass spectrometry method for thequantification of rofecoxib in pharmacokinetic studies with humans

An easy, rapid and selective method for the determination of rofecoxib in h uman plasma is presented. The analytical technique is based on reversed-pha se high-performance liquid chromatography coupled to atmospheric pressure c hemical ionisation mass spectrometry (Finnigan Mat LCQ ion trap). The reten tion time of rofecoxib was 1.2 min. The method has been validated over a li near range from 1 to 500 mug/1 using celecoxib as internal standard. After validation, the method was used to study the pharmacokinetic profile of rof ecoxib in 12 healthy volunteers after administration of a single oral dose (12.5 mg). The presented method was sufficient to cover more than 95% of th e area under the curve. The pharmacokinetic characteristics (mean +/- SD) w ere t(max): 2.4 +/- 1.0 h, c(max): 147 +/- 34 mug/1, AUC(x): 2038 +/- 581 m ug h/1 and t(1/2): 11.3 +/- 2.1 h. (C) 2001 Elsevier Science B.V. All right s reserved.