Analytical method development and validation for simultaneous estimation of sitagliptin and etruglifloxin in bulk and pharmaceutical dosage form by RP-HPLC

A simple, specific and accurate reverse phase high performance liquid chromatographic method was developed for the simultaneous determination Sitagliptinand Etruglifloxinin pharmaceutical dosage form. The column used was Discovery C18(250mm x 4.6 mm, 5m)in isocratic mode, with mobile phase containing phosphatebufferandacetonitrile (45:55v/v). The buffer is prepared by adding accurately weighed 1.36gm of PotassiumdihyrogenOrtho phosphate in a 1000ml of Volumetric flask add about 900ml of milli-Q water added and degas to sonicate and finally make up the volume with water then pH adjusted to 5.4with dil. Orthophosphoric acid solution.The flow rate was 1.0ml/ min and effluents were monitored at 260nm. The retention times of Sitagliptinand Etruglifloxinwere found to be 2.381min and 3.429min, respectively. The linearity for Sitagliptinand Etruglifloxinwere in the range of 25-150μg/mland 3.75-22.5μg/ml respectively. The recoveries of Sitagliptinand Etruglifloxinwere found to be 99.46to 101.19% and 99.36to 100.99%, respectively. The proposed method was validated and successfully applied to the estimation of Sitagliptinand Etruglifloxinin combined tablet dosage forms.