Quantitative Analysis of β-Blockers in Human Plasma by Reversed-Phase Ion-Pair High-Performance Liquid Chromatography Using a Microbore Column

Abstract

HPLC assays for four β-blockers (namely atenolol, labetalol, metoprolol and propranolol) in human plasma have been developed using a reversed-phase microbore column. Sodium dodecyl sulphate (SDS) was chosen as the pairing ion. SDS concentration was varied to provide acceptable retention for the drugs of interest and good resolution from plasma interfering peaks. Based on these results, a general reversed-phase ion-pair HPLC elution scheme using microbore column (ODS-Hypersil) with fluorescence or UV detection was developed. the detection limits were 10, 5, 5 and 1 ng/ml for atenolol, labetalol, metoprolol and propranolol, respectively. the coefficients of variation for the drugs studied were less than 10%. These methods have been shown to be suitable for routine analysis in bioavailability studies and for studying the placental transfer of β-blockers in both human placental perfusion and the animal models.