Quantitative determination of icotinib in human plasma and urine using liquid chromatography coupled to tandem mass spectrometry

We developed a rapid, specific and sensitive method based on high performance liquid chromatography coupled to tandem mass spectrometry (HPLC–MS/MS) to determine icotinib concentrations in human plasma and urine. Liquid–liquid extraction (LLE) and direct dilution were firstly used to isolate icotinib from plasma and urine followed by injection of the extracts onto a C18 column with gradient elution. Ionization of icotinib and midazolam (internal standard, IS) was performed using an electrospray ionization source in positive mode and detection was carried out in multi-reaction monitoring (MRM) mode. The lower limits of quantitation (LLoQ) of icotinib in human plasma and urine by this method were 0.1 and 1.00 ng/mL, respectively. The accuracy, precision, specificity, recovery, matrix effect, linearity and several of stabilities have been validated for icotinib in human plasma and urine. In conclusion, the validation results showed that this method is robust, specific and sensitive and it can successfully fulfill the requirement of clinical pharmacokinetic study of icotinib hydrochloride in Chinese healthy subjects.