Simultaneous Estimation of Saxagliptin and Dapagliflozin in Human Plasma by Validated High Performance Liquid Chromatography - Ultraviolet Method

Objectives: The fixed dose combination of saxagliptin and dapagliflozin is a recently approved antidiabetic medication. It is marketed under the brand name Qtern. The aim of this study was to develop a simple, rapid, sensitive, and validated isocratic reversed phase-high performance liquid chromatography (RP-HPLC) method for the simultaneous estimation of saxagliptin and dapagliflozin in human plasma using linagliptin as internal standard as per US-Food and Drug Administration guidelines. Materials and Methods: The method was performed on a Waters 2695 HPLC equipped with a quaternary pump. The analyte separation was achieved using an Eclipse XDB C18 (150 x 4.6 mm x 5 mu m) column with a mobile phase consisting of 0.1% ortho phosphoric acid and acetonitrile (50: 50) with pH adjusted to 5.0 at 1 mL/min flow rate. Results: The analyte was detected at 254 nm. The retention time of the internal standard, saxagliptin, and dapagliflozin was 2.746, 5.173, and 7.218 min, respectively. The peaks were found to be free of interference. The method was validated over a dynamic linear range of 0.01 to 0.5 mu g/mL and 0.05 to 2 mu g/mL for saxagliptin and dapagliflozin, respectively, with a correlation coefficient of 0.998. The precision and accuracy of samples of six replicate measurements at lower limits of quantification level were within the limits. The analytes were found to be stable in human plasma at -28 degrees C for 37 days. Conclusion: The stability, sensitivity, specificity, and reproducibility of this method make it appropriate for the determination of saxagliptin and dapagliflozin in human plasma.