A LC-MS/MS method for simultaneous estimation of a novel anti-diabetic combination of saxagliptin and dapagliflozin using a polarity switch approach: application to in vivo rat pharmacokinetic study

Diabetes and its associated concerns constitute a major growing health issue in modern society. In the current work we report a highly sensitive, selective and specific LC-MS/MS method for the estimation of a novel anti-diabetic combination of saxagliptin (SAX) and dapagliflozin (DAP) in rat plasma. An Agilent Eclipse Plus C18 column (150 mm x 4.6 mm, 3.6 m) with gradient elution using 0.01% ammonia solution and acetonitrile as the mobile phase was used for the chromatographic separation. The ion transitions were quantified in positive and negative polarity using a polarity switching approach. A solid phase extraction process was used as the sample preparation approach. The method provided good linearity over the range of 0.2-80 ng mL(-1) for SAX and 5-2000 ng mL(-1) for DAP. The method was validated according to US FDA bioanalytical guidelines and successfully applied in a preclinical study for simultaneous quantification of SAX and DAP in SD rats. The developed analytical method can also be utilized for the future clinical applications of both the drugs in combined dosage form.