SOLID-PHASE EXTRACTION ON STYROSORB CARTRIDGES AS A SAMPLE PRETREATMENT METHOD IN THE STEREOSELECTIVE ANALYSIS OF PROPRANOLOL IN HUMAN SERUM

Sample pretreatment using solid-phase extraction (SPE) on cartridges f illed with small-particle Styrosorb porous polystyrene-based sorbent h as been used in the analysis of propranolol enantiomers in human serum by highperformance liquid chromatography (HPLC) with fluorescent dete ction. SPE on Sep-Pak C-18 cartridges was used as a reference pretreat ment method. The propranolol content of the samples was determined by achiral normal-phase HPLC and the enantiomeric ratio of propranolol (S IR) was then determined by chiral HPLC on a column with silica-bonded cellulose-tris(3,5-dimethylphenyl carbamate). Recoveries of propranolo l from serum using SPE on Styrosorb and C-18 phases were 97+/-5% and 9 6+/-5%, respectively. Detection and quantification limits for proprano lol enantiomers were 4 and 7 ng/ml, respectively.