Quantitative determination of azithromycin in human plasma by ultra performance liquid chromatography-electrospray ionization mass spectrometry and its application in a pharmacokinetic study
Chen, L.; Qin, F.; Ma, Y.; Li, F.
Journal of Chromatography. B Analytical Technologies in the Biomedical and Life Sciences 855(2): 255-261
ISSN/ISBN: 1570-0232 PMID: 17574935 DOI: 10.1016/j.jchromb.2007.05.016
A selective, rapid and sensitive ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed for the quantitative determination of azithromycin in human plasma and its application in a pharmacokinetic study. With roxithromycin as internal standard, sample pretreatment involved a one-step extraction with diethyl ether of 0.5 mL plasma. The analysis was carried out on an ACQUITY UPLC BEH C(18) column (50 mm x 2.1 mm, i.d., 1.7 microm) with gradient elution at flow rate of 0.35 mL/min. The mobile phase was 50 mM ammonium acetate and acetonitrile. The detection was performed on a triple-quadrupole tandem mass spectrometer by multiple reaction monitoring (MRM) mode via electrospray ionization (ESI). Linear calibration curves were obtained in the concentration range of 1-1000 ng/mL, with a lower limit of quantification of 1 ng/mL. The intra- and inter-day precision (RSD) values were below 15% and accuracy (RE) was -1.3% to 5.7% at all QC levels. The method was applicable to clinical pharmacokinetic study of azithromycin in healthy volunteers following oral administration.