title: Enantioselective determination of isradipine in human serum using chiral stationary phase liquid chromatography and gas chromatography with nitrogen selective detection.
abstract: rac-Isradipine is a dihydropyridine type calcium antagonist. Its calcium entry blocking effect is due primarily to the (+)-(S)-enantiomer. This study describes a sensitive enantioselective method for the determination of isradipine in human serum. Following alkaline extraction into hexane, the enantiomers of isradipine are separated quantitatively by high-performance liquid chromatography on a Chiralcel OJ column at 39 degrees C. The collected fractions were evaporated and assayed using capillary gas chromatography on a HP 50+ column with nitrogen selective detection. Using 2.0 ml of serum, 0.7 nmol/1 (0.26 ng/ml) of each enantiomer could be determined with acceptable precision. The method has successfully been used to measure (+)-(S)- and (-)-(R)-isradipine concentrations in samples from volunteers after intravenous and oral administration of isradipine.
authors.affiliation: Department of Clinical Biochemistry, Bispebjerg Hospital, Copenhagen, Denmark.
authors.forename: H S
authors.initials: HS
authors.lastname: Rask
authors.forename: H R
authors.initials: HR
authors.lastname: Angelo
authors.forename: H R
authors.initials: HR
authors.lastname: Christensen
mesh_terms: D002121:Calcium Channel Blockers / Q000097:blood*; D002849:Chromatography, Gas; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D017275:Isradipine / Q000097:blood*; D013237:Stereoisomerism
chemical_list: D002121:Calcium Channel Blockers; D017275:Isradipine