Background: The development of sound bioanalytical LC-MS (liquid chromatography-mass
spectroscopy) method(s) is of paramount importance during the process of drug discovery, development
and culminating in a marketing approval. The use of oral antidiabetic agents has been increased
significantly from the last decades and till now no bioanalytical method is available for quantitation of
sitagliptin (SG) and ertugliflozin (EG) in biological matrix which can be applied to pharmacokinetic
studies using LC-MS/MS.
Objective: To develop a new, rapid and sensitive LC-MS/MS method for the simultaneous estimation
of sitagliptin (SG) and ertugliflozin (EG) in rat plasma by Liquid-Liquid Extraction method (LLE) using
deutereated sitagliptin (SGd6) and ertugliflozin (EGd6).
Methods: Chromatographic separation was carried out on a reverse phase Waters, Xetrra C18 (150mm x
4.6mm, 2μm) column using a mixture of acetonitrile and OPA buffer (50:50v/v) at a flow rate of
1ml/min in isocratic mode. Quantification was achieved using an electrospray ion interface operating in
positive mode, under Multiple Reaction Monitoring (MRM) conditions.
Results: The method showed excellent linearity over the concentration range of 5.00- 75.00pg/mL for
sitagliptin and 0.75- 11.35pg/mL ertugliflozin. The intra-batch and inter batch precision (%CV) was ≤
4.3% and matrix effect (%CV) was 0.02% and 0.12% for sitagliptin at HQC and LQC, respectively.
Matrix effect (%CV) was 0.08% and 0.33% for ertugliflozin at HQC and LQC, respectively.
Conclusion: The simplicity of the method allows for application in laboratories, presents a valuable
tool for pharmacokinetic studies. The particular assay has been proficiently put on pharmacokinetic
study in rats subjects.