LC-MS/MS Determination of Empagliflozin and Metformin.

A new LC-MS/MS method was developed for determination of empagliflozin and metformin. Bridged Ethylene Hybrid C18 column (50 mm × 2.1 mm, 1.7 μm), isocratic elution based on 0.1% aqueous formic acid:acetonitrile (75:25, v/v) as a mobile phase, column temperature at 55°C and flow rate at 0.2 mL min-1 were used. The mass spectrometer was operated under multiple reaction monitoring mode using electrospray ionization by monitoring the transition pairs (precursor to product ion) of m/z 451.04-71.07 for empagliflozin and m/z 130.11-71.14 for metformin in the positive mode. The validation parameters were acceptable over concentration ranges of 5-1,000 ng mL-1 and 50-25,000 ng mL-1 for empagliflozin and metformin, respectively. The optimized method was validated according to International Conference on Harmonization guidelines. Regression parameters, limit of detection, limit of quantification, accuracy, precision and pharmaceutical formulation analysis were investigated. The developed method was proved to be accurate for the quality control of recently approved Synjardy® tablets.