A high-performance liquid chromatography-tandem mass spectrometry method for simultaneous determination of imigliptin, its five metabolites and alogliptin in human plasma and urine and its application to a multiple-dose pharmacokinetic study.

Imigliptin is a novel DPP-4 inhibitor, designed to treat type 2 diabetes mellitus (T2DM). A selective and sensitive method was developed using high performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS) to simultaneously quantify imigliptin, its five metabolites, and alogliptin in human plasma and urine. Solid-phase extraction (SPE) and direct dilution were used to extract imigliptin, its five metabolites, alogliptin from plasma and urine, respectively. The extracts were injected onto a SymmetryShield RP8 column with a gradient elution of methanol and water containing 10 mM ammonium formate (pH = 7). Ionization of all analytes was performed using an electrospray ionization (ESI) source in positive mode and detection was carried out with multiple reaction monitoring (MRM) mode. The results revealed that the method had excellent selectivity and linearity. Inter- and intra-batch precisions of all analytes were less than 15% and the accuracies were within 85%-115% for both plasma and urine. The sensitivity, matrix effect, extraction recovery, linearity, and stabilities were validated for all analytes in human plasma and urine. In conclusion, the validation results showed that this method was robust, specific, and sensitive and it can successfully applied to a pharmacokinetic study of Chinese T2DM subjects after oral dose of imigliptin and alogliptin.