Stereoselective determination of the major ibuprofen metabolites in human urine by off-line coupling solid-phase microextraction and high-performance liquid chromatography

• Published in: Analytica chimica acta 2005-05, Vol.538 (1), p.25-34
• Main Authors: de Oliveira, Anderson Rodrigo Moraes, de Santana, Fernando José Malagueño, Bonato, Pierina Sueli
• Format: Article
• Language: English
• Subjects: 2-Hydroxyibuprofen; Analytical chemistry; Carboxyibuprofen; Chemistry; Chromatographic methods and physical methods associated with chromatography; Enantiomeric separation; Exact sciences and technology; Ibuprofen metabolites; Off-line solid-phase microextraction; Other chromatographic methods; Urine
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/j.aca.2005.01.058

A simple, rapid and sensitive off-line solid-phase microextraction method coupled to high-performance liquid chromatography was developed for the stereoselective analysis of the major ibuprofen metabolites in human urine samples. For this purpose, a carbowax/templated/resin coated fiber was used. Several parameters influencing the efficiency of the analyte extraction were explored. The chromatographic separation was achieved on a Chiralpak AS column using hexane:isopropanol (95:5 v/v) plus 0.05% trifluoroacetic acid as the mobile phase, at a flow-rate of 1.2 mL/min. Detection was carried out at 230 nm. The mean recoveries were between 1.4 and 1.6%, with R.S.D. values lower than 9.5 for both 2-OHIbu enantiomers, and between 3.7 and 5.7%, with R.S.D. values lower than 13.4 for all four COOHIbu stereoisomers. The method was linear over the 5–50 μg/mL concentration range and the quantification limit was 5 μg/mL for all metabolite stereoisomers. Within-day and between-day assay precision and accuracy for both metabolites were studied at three concentration levels of each stereoisomer (15, 30 and 45 μg/mL) and were lower than 15%.