A highly efficient and sensitive LC-MS/MS method for the determination of afatinib in human plasma: application to a metabolic stability study

Afatinib (AFT) is a new tyrosine kinase inhibitor approved for the treatment of nonsmall cell lung cancer. In the present study, a simple, specific, rapid and sensitive liquid chromatography tandem mass-spectrometric method for the quantification of AFT in human plasma, was developed and validated. Chromatographic separation of the analytes was accomplished on a reversed-phase Luna((R))-PFP 100 angstrom column (50x2.0mm; 3.0m) maintained at ambient temperature. Isocratic elution was carried out using acetonitrile-water (40:60, v/v) containing 10mm ammonium formate buffer (pH4.5) adjusted with formic acid at a flow rate of 0.4mLmin(-1). The analytes were monitored by electrospray ionization in positive ion multiple reaction monitoring mode. The method yields a linear calibration plot (r(2)=0.9997) from a quantification range of 0.5-500ngmL(-1) with the lower limit of quantification and lower limit of detection of 1.29 and 0.42ngmL(-1), respectively. The intra- and inter-day precision and accuracy were estimated and found to be in the ranges of 1.53-4.11% for precision and -2.80-0.38% for accuracy. Finally, quantification of afatinib in a metabolic stability study in rat liver microsomes was achieved through the proposed method. Copyright (c) 2016 John Wiley & Sons, Ltd.