RP-HPLC Method Development for Estimation of Diclofenac Diethylamine Topical Solution

Objective: A simple, rapid, precise, and reproducible RP-HPLC method development and validation for estimation of Diclofenac Diethylamine in Topical Solution. Experimental condition: The method was developed using Kromasil C8 (150 mm × 4.6 mm, 5 µm) column. Mobile phase composition was Buffer: Methanol (25:75 %V/V) (Buffer-1.37 g of NaH2PO4 in 1000 ml adjust pH 2.5 ± 0.05 with OPA.), flow rate 1 ml/min and detection carried out at 254 nm at column temperature 40ºC. The injection volume was 10µl with run time of 10 minutes. Diluent used was Methanol: Water (50:50 % V/V). Results: The retention time for Diclofenac Diethylamine was found 5.26 minute. Method found linear in the range of 50-150 µg/ml (r2 = 0.9998). Percentage Recovery was 100.5-100.9 %. The RSD for Diclofenac Diethylamine are less than 2 for precision, specificity, robustness respectively. Conclusion: A simple and rapid RP-HPLC method was developed for the estimation of Diclofenac Diethylamine in pure API and Topical formulation. The method was validated as per ICH guideline and statistical data confirmed Specificity, Linearity, Accuracy, Precision and Robustness of proposed method.