Development and validation of an RP-HPLC method for simultaneous determination of sitagliptin and valsartan

Background: Diabetes mellitus and hypertension are commonly coexisting diseases and combination therapies are required to improve therapeutic outcomes and patient compliance. Objectives: Current research aims to develop and validate a precise reverse-phase High-Performance Liquid Chromatography (RP-HPLC) method for the concurrent determination of sitagliptin and valsartan. Methods: For analysis, an Agilent 1260 Infinity II HPLC system provided with a C-18 column was used. The method was validated as per the ICH guidelines. Results: Calibration curves confirmed excellent linearity for sitagliptin and valsartan with R² values exceeding 0.99. The limits of detection (LOD) and quantification (LOQ) were calculated as 8.5 ppm and 25.7 ppm for sitagliptin and 7.8 ppm and 23.5 ppm for valsartan, respectively. Recovery studies and robustness confirmed method accuracy and indicated no significant impact from small variations in chromatographic parameters. Conclusion: In conclusion, this validated RP-HPLC method is consistent and efficient for compliance with pharmaceutical standards.