Development and Validation of HPLC Method for Diphenhydramine Hydrochloride

Abstract

Aim: The aim of present method development for Diphenhydramine HCl performed on HPLC is to obtain specific, more accurate and precise results as compare to spectrophotometric method. Methods: HPLC analysis was performed according to USP method with wavelength detection at 220nm and 1.0ml/min flow rate. Wufeng thermo HPLC system UV -100detector was used having column C18(4.6mm*250mm) 5. Methanol and water (4:1) mixture was used as mobile phase and pH was adjusted at 7.4 with the help of triethanolamine. Validation parameters like linearity, accuracy, precision, solution stability, robustness, LOD, LOQ and system suitability were successfully evaluated. Results: The regression co-efficient for calibration curve was 0.991 and % recovery was in range (80-110%), whereas no robustness was observed in this reported method. Conclusion: In summary, the expected linearity, accuracy and % recovery indicating that HPLC is more precise method than spectrophotometry and suggested that present method qualifies the validation criteria.