A HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC METHOD FOR THE DETERMINATION OF ALBUTEROL ENANTIOMERS IN HUMAN SERUM USING SOLID-PHASE EXTRACTION AND A SUMICHIRAL-OA CHIRAL STATIONARY-PHASE

A chiral high performance liquid chromatographic method was developed for the simultaneous assay of S(+) and R(-) albuterol in human serum. The assay utilizes solid-phase extraction on a silica column as a sample clean-up step. The chiral separation was accomplished under isocratic conditions using a Sumichiral OA 4700 column and a mobile phase consisting of 350:410:46:2 v/v/v/v hexane/methylene chloride/absolute methanol/trifluoroacetic acid at a flow rate of 1.0 mL/min. The enantiomers were measured using fluorescence detection set at 228 nm excitation and an emission filter of >280nm. Racemic atenolol was used as internal standard. Drug to internal standard peak height ratios were linear over a 2-20 ng/mL range for each enantiomer. The limit of detection of each analyte was 2.0 ng/mL (S/N=3). The lowest quantifiable level of each enantiomer was 3 ng/mL.