title: Liquid chromatographic determination of the macrolide antibiotics roxithromycin and clarithromycin in plasma by automated solid-phase extraction and electrochemical detection.
abstract: A liquid chromatographic method for the determination of the macrolide antibiotics, roxithromycin and clarithromycin, in plasma is described. The method is fully automated, employing on-line solid-phase extraction for sample clean-up, using the Prospekt unit. Plasma samples, mixed with internal standard, were injected onto exchangeable CN cartridges. After washing, the compounds were eluted and transferred to a C18 analytical column for separation and electrochemical detection. Clarithromycin was used as internal standard when assaying roxithromycin and vice versa. The recovery of the solid-phase extraction method was 90% and higher, and the relative standard deviation was about 3%. The limit of quantitation was 0.5 mumol/l when 25 microliters of plasma was injected. Comparison with a liquid-liquid extraction method for sample clean-up showed good agreement.
authors.affiliation: Astra Hässle AB, Mölndal, Sweden.
authors.forename: M
authors.initials: M
authors.lastname: Hedenmo
authors.forename: B M
authors.initials: BM
authors.lastname: Eriksson
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D017291:Clarithromycin / Q000097:blood*; D004563:Electrochemistry; D006801:Humans; D015203:Reproducibility of Results; D015575:Roxithromycin / Q000097:blood*
chemical_list: D015575:Roxithromycin; D017291:Clarithromycin