Simultaneous determination of six tyrosine kinase inhibitors in human plasma using HPLC-Q-Orbitrap mass spectrometry

Aim: Gefitinib, erlotinib, icotinib, crizotinib, lapatinib and apatinib are targeted cancer therapy agents acting through inhibition of tyrosine kinase. Method for quantifying these six drugs in human plasma of patients was required. Materials & methods: An HPLC-Q-Orbitrap method (based on HPLC–MS/MS) was developed and validated for the simultaneous detection and quantitation of six tyrosine kinase inhibitors in human plasma. Sample was extracted by liquid–liquid extraction (ethyl acetate: tert-Butyl methyl ether, 1:1 v/v). The method shows a high level of accuracy and reproducibility. The lower limit of quantification was 0.02 ng/ml for apatinib, 0.1 ng/ml for crizotinib, 2.0 ng/ml for lapatinib and 0.05 ng/ml for erlotinib, gefitinib and icotinib. This method was successfully used for apatinib monitoring in plasma of patients with NSCLC. Conclusion: This simple and reproducible method has potential for monitoring of tyrosine kinase inhibitors in patients’ plasma.