Determination of deracoxib in feline plasma samples using high performance liquid chromatography

A new HPLC procedure for the determination of deracoxib, a selective cyclooxygenase-2 inhibitor, has been developed and validated. Following a liquid-liquid extraction using isopropyl alcohol and chloroform, samples were separated by isocratic reversed-phase HPLC on an Atlantis C-18 column and quantified using UV detection at 252 nm. The mobile phase was a mixture of 10 mM potassium phosphate (pH 4.5) and acetonitrile, with a flow-rate of 1.0 ml/min. The procedure produced a linear curve over the concentration range 10-1500 ng/ml. The development of the assay allowed the determination of pharmacokinetic parameters after oral administration of deracoxib in cats and would be suitable for other pharmacokinetic studies. (c) 2005 Elsevier B.V. All rights reserved.