Determination by high-performance liquid chromatography of ketoprofen in vitro in rat skin permeation samples

A direct, simple and rapid high-performance liquid chromatographic method has been developed for the determination of ketoprofen with ibuprofen as internal standard. Samples were chromatographed on a 5 microm Kromasil 100 C18 column. The mobile phase was a mixture of acetonitrile-0.01 M KH2PO4 adjusted to pH 1.5 with orthophosphoric acid 85% (60:40, v/v). Detection was at 260 nm and the run time was 10 min. The detector response was found to be linear in the concentration range 0.02 to 40 microg/ml. This HPLC assay has been applied to measure the "in vitro" percutaneous penetration of ketoprofen through rat skin.