title: Improved HPLC method for the determination of moxifloxacin in application to a pharmacokinetics study in patients with infectious diseases.
abstract: Objective. To develop a simple and rapid high-performance liquid chromatography (HPLC) method for measuring moxifloxacin concentration in human plasma. Methods. Following a single step liquid-liquid extraction, analytes along with an internal standard (IS) were separated using an isocratic mobile phase of 0.1% triethylamine (adjusted pH to 4.8 with phosphoric acid)/acetonitrile (80/20, v/v) at flow rate of 1 mL/min on reverse phase Kromasil C18 column (250 mm × 4.6 mm, 5  μ m) at room temperature. Results. Total analytical run time for selecting moxifloxacin was 15 min. The assays exhibited good linearity (r (2) = 0.9998) over the studied range of 25 to 5000 ng/mL. The absolute recovery rate of low, medium, and high concentrations were 69.88%, 78.86%, and 78.51%, respectively. The relative recovery rates were 98.50%, 96.61%, and 101.79%, respectively. Coefficient of variation and error at both of the intraday and interday assessments were less than 4.7%. Conclusions. The results indicated that this method is a simple, rapid, precise and accurate assay for the determination of moxifloxacin concentrations in human plasma. This validated method is sensitive and reproducible enough to be used in pharmacokinetic studies.
authors.affiliation: Pharmacy Department, The Third Central Hospital, No. 83 Jintang Road, Hedong District, Tianjin 300170, China ; Basic Medical Department, Tianjin Medical University, No. 22 Qixiangtai Road, Heping District, Tianjin 300070, China.
authors.forename: Nan
authors.initials: N
authors.lastname: Wang
authors.forename: Liqin
authors.initials: L
authors.lastname: Zhu
authors.forename: Xuequn
authors.initials: X
authors.lastname: Zhao
authors.forename: Wenjie
authors.initials: W
authors.lastname: Yang
authors.forename: He
authors.initials: H
authors.lastname: Sun