title: Rapid and automated determination of the beta2-agonist reproterol in human plasma by atmospheric pressure chemical ionisation high-performance liquid chromatography-tandem mass spectrometry.
abstract: An on-line HPLC assay with tandem mass spectrometric detection for the fast and sensitive determination of reproterol in human plasma was developed, utilising a methylated structural analogue as the internal standard. Automated solid-phase extraction of diluted plasma samples, based on 250 microl plasma aliquots, at pH 6.5, allowed a reliable quantification of reproterol down to 400 pg/ml. Injection of 100 microl of plasma extracts onto a 30 mm x 4.6 mm reversed-phase guard column provided retention times ranging from 20 to 30 s for reproterol and the internal standard. The standard curves were linear from 0.2 to 200 ng/ml using weighted linear regression analysis (1/y2). The inter-assay and intra-assay accuracies were -0.9% and +3.2%, exhibiting a precision (C.V.) of +/- 11% and +/- 9.3%, respectively. Up to 100 unknowns may be analysed each 24 h per analyst.
authors.affiliation: Department of Biological Research Biochemistry, ASTA Medica AG, Frankfurt, Germany.
authors.forename: N G
authors.initials: NG
authors.lastname: Knebel
authors.forename: M
authors.initials: M
authors.lastname: Winkler
mesh_terms: D000280:Administration, Inhalation; D000284:Administration, Oral; D000318:Adrenergic beta-Agonists / Q000008:administration & dosage / Q000097:blood* / Q000737:chemistry / Q000493:pharmacokinetics; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D002940:Circadian Rhythm; D004338:Drug Combinations; D006801:Humans; D013058:Mass Spectrometry / Q000379:methods*; D009921:Metaproterenol / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000097:blood / Q000737:chemistry / Q000493:pharmacokinetics; D009862:Online Systems; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013806:Theophylline / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000097:blood / Q000737:chemistry / Q000493:pharmacokinetics; D013997:Time Factors
chemical_list: D000318:Adrenergic beta-Agonists; D004338:Drug Combinations; C014792:reproterol; D009921:Metaproterenol; D013806:Theophylline