Determination of celecoxib in human plasma by normal-phase high-performance liquid chromatography with column switching and ultraviolet absorbance detection

A method is described for the determination of celecoxib in human plasma. S amples were extracted using 3M Empore membrane extraction cartridges and se parated under normal-phase HPLC conditions using a Nucleosil-NO2 (150x4.6 m m, 5 mu m) column. Detection was accomplished using UV absorbance at 260 nm . The HPLC method included a column switching procedure, in which late elut ing compounds were diverted to waste, to reduce run-time to 12 min. The ass ay was linear in the concentration range of 25-2000 ng/ml when 1-ml aliquot s of plasma were extracted. Recoveries of celecoxib were greater than 91% o ver the calibration curve range. Intraday precision and accuracy for this a ssay were 5.7% C.V. or better and within 2.3% of nominal, respectively. The assay was used to analyze samples collected during human clinical studies. (C) 2000 Elsevier Science B.V. All rights reserved.