title: Determination of the theophylline solubilizer salicylamide-O-acetic acid in serum and urine using high-performance liquid chromatography.
abstract: A high-performance liquid chromatographic method for the determination of the theophylline solubilizer salicylamide-O-acetic acid has been developed in the range 0.5 to 10 microg/ml for human serum and 5 to 400 microg/ml for urine. Reversed-phase ion-pair chromatography was employed with tetrabutylammonium hydrogen sulphate as counterion and 2-nitrophenylacetic acid as internal standard. Preliminary pharmacokinetic single-dose studies show that the sensitivity and the selectivity of the assay are adequate to measure lower concentrations in the late beta-phase.
authors.affiliation: Department of Angiology and Geriatrics, Medical University Lübeck, Ratzeburger Allee 160, D-2400 Lübeck, Federal Republic of Germany.
authors.forename: H U
authors.initials: HU
authors.lastname: Schulz
authors.forename: E
authors.initials: E
authors.lastname: Kraas