title: Sensitive liquid chromatography/mass spectrometry assay for the quantification of azithromycin in human plasma.
abstract: A simple, rapid, sensitive and specific liquid chromatography/electrospray ionization mass spectrometry method was developed and validated to quantify azithromycin in human plasma, using erythromycin as the internal standard (IS). A simple sample preparation method of protein precipitation with methanol was employed. Methanol, acetonitrile and water (12:30:58, v/v/v) were used as the isocratic mobile phase, with 0.1% formic acid and 0.1% ammonium acetate in water. Selected ion monitoring was specific for azithromycin and erythromycin. The assay was linear over the concentration range 4.69-600 ng/mL. The correlation coefficients for the calibration curves ranged from 0.9994 to 0.9998. The intra- and inter-day precisions, calculated from quality control samples, were less than 8.24%. The method was employed in a pharmacokinetic study after oral administration of 500 mg azithromycin dispersible tablet to 20 healthy volunteers.
authors.affiliation: Department of Chemistry, University of Science and Technology of China, Hefei, PR China.
authors.forename: Fei
authors.initials: F
authors.lastname: Liu
authors.forename: Yu
authors.initials: Y
authors.lastname: Xu
authors.forename: Jinchang
authors.initials: J
authors.lastname: Huang
authors.forename: Shu
authors.initials: S
authors.lastname: Gao
authors.forename: Qingxiang
authors.initials: Q
authors.lastname: Guo
mesh_terms: D000097:Acetonitriles / Q000737:chemistry; D000900:Anti-Bacterial Agents / Q000097:blood* / Q000493:pharmacokinetics; D017963:Azithromycin / Q000097:blood* / Q000493:pharmacokinetics; D001681:Biological Assay; D011232:Chemical Precipitation; D002853:Chromatography, Liquid / Q000379:methods*; D004917:Erythromycin / Q000592:standards; D006801:Humans; D000432:Methanol / Q000737:chemistry; D012015:Reference Standards; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012997:Solvents / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D013997:Time Factors; D014867:Water / Q000737:chemistry
chemical_list: D000097:Acetonitriles; D000900:Anti-Bacterial Agents; D012997:Solvents; D014867:Water; D004917:Erythromycin; D017963:Azithromycin; D000432:Methanol; C032159:acetonitrile