Determination of tigecycline in human plasma by LC-MS/MS and its application to population pharmacokinetics study in Chinese patients with hospital-acquired pneumonia

A selective, sensitive and rapid liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the determination of tigecycline (TGC) in human plasma, using tigecycline-d(9) as an internal standard (IS). Analytical samples were prepared using a protein precipitation method coupled with a concentration process. The analyte and IS were separated on a reversed-phase Waters Acquity UPLC (R) BEH-C-18 column (2.1x50mm i.d., 1.7m) with a flow rate of 0.25mL/min. The mobile phase consisted of water, containing 0.2% formic acid (v/v) with 10mm ammonium formate (A) and acetonitrile (B). The mass spectrometer was operated in selected reaction monitoring mode through electrospray ionization ion mode using the transitions of m/z 586.2513.1 and m/z 595.1514.0 for TGC and IS, respectively. The linearity of the method was in the range of 10-5000ng/mL. Intra- and inter-batch precision (CV) for TGC was <9.27%, and the accuracy ranged from 90.06 to 107.13%. This method was successfully applied to the analysis of samples from hospital-acquired pneumonia patients treated with TGC, and a validated population pharmacokinetic model was established. This developed method could be useful to predict pharmacokinetics parameters and valuable for further pharmacokinetics/pharmacodynamics studies.