title: Column-switching high-performance liquid chromatographic determination of clarithromycin in human plasma with electrochemical detection.
abstract: A column-switching HPLC method was described for the direct analysis of clarithromycin in human plasma using electrochemical detector without sample pre-purification step. Plasma samples were diluted with washing solvent, i.e. acetonirile-methanol-0.05 M potassium phosphate buffer (pH 7.0) (5:2:93, v/v) and then, injected to the precolumn. After plasma proteins had flowed out from the precolumn, clarithromycin and internal standard (roxithromycin) were eluted to a Luna 2 C(18) column and separated with acetonitrile-methanol-0.05 M potassium phosphate buffer (pH 7.0) (41:6:53, v/v). Electrochemical oxidation of clarithromycin occurred at 0.87 V vs. Ag/AgCl reference electrode with glassy carbon electrode. The calibration curve was linear in the concentration range 0.1-4 mug ml(-1) with correlation coefficient of 0.998. This method showed excellent precision (RSD 3.8% at 0.1 mug ml(-1)) and accuracy (+/-2%) with the total analysis time per sample of 30 min. The present method was successfully applied to the pharmacokinetic study of clarithromycin in volunteers receiving a single oral administration of clarithromycin.
authors.affiliation: Bioanalysis Laboratory, College of Pharmacy, Wonkwang University, Iksan 570-749, South Korea.
authors.forename: S J
authors.initials: SJ
authors.lastname: Choi
authors.forename: S B
authors.initials: SB
authors.lastname: Kim
authors.forename: H Y
authors.initials: HY
authors.lastname: Lee
authors.forename: D H
authors.initials: DH
authors.lastname: Na
authors.forename: Y S
authors.initials: YS
authors.lastname: Yoon
authors.forename: S S
authors.initials: SS
authors.lastname: Lee
authors.forename: J H
authors.initials: JH
authors.lastname: Kim
authors.forename: K C
authors.initials: KC
authors.lastname: Lee
authors.forename: H S
authors.initials: HS
authors.lastname: Lee