title: Enantioselective analysis of atenolol in biologic fluids: comparison of liquid-liquid and solid-phase extraction methods.
abstract: In this study we evaluated a liquid-liquid extraction procedure and a solid-phase extraction procedure for sample preparation for the enantioselective analysis of atenolol in plasma and urine by high-performance liquid chromatography. A Chiralcel OD-H column was used for the resolution of atenolol enantiomers with hexane-ethanol (85:15, v/v) plus 0.1% diethylamine as the mobile phase. In the liquid-liquid extraction procedure, atenolol was extracted from alkalinized body fluids with 5 ml chloroform-2-propanol (4:1, v/v). In the solid-phase extraction procedure, atenolol was isolated from plasma using a C8 column and methanol. Both extraction procedures were efficient in recovering atenolol and removing endogenous interferents. The RSDs and deviation from nominal values were lower than 10% for both within-day and between-day assays. The results show that there were no statistically significant differences in between-day variation. The t-test showed that there were no significant differences between the real concentrations and the determined concentrations. The limit of quantitation was 10 ng/ml and the linear range was 10-5,000 ng/ml for both methods. These methods can be used in pharmacokinetic studies.
authors.affiliation: Departamento de Química, Faculdade de Filosofia Ciencias e Letras de Ribeirão Preto-USP, Brazil.
authors.forename: Maria Helena
authors.initials: MH
authors.lastname: Iha
authors.forename: Alexandre Souto
authors.initials: AS
authors.lastname: Martinez
authors.forename: Pierina Sueli
authors.initials: PS
authors.lastname: Bonato
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000032:analysis* / Q000097:blood / Q000652:urine; D001262:Atenolol / Q000032:analysis* / Q000097:blood / Q000652:urine; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D012015:Reference Standards; D015203:Reproducibility of Results; D013050:Spectrometry, Fluorescence; D013237:Stereoisomerism
chemical_list: D000319:Adrenergic beta-Antagonists; D001262:Atenolol