METHOD DEVELOPMENT AND VALIDATION FOR THE SIMULTANEOUS ESTIMATION OF SULFAMETHOXAZOLE AND TRIMETHOPRIM BY RP-HPLC

Objective: A simple, Accurate, precise method was developed for the simultaneous estimation of the Sulfamethoxazole and Trimethoprim in pharmaceutical dosage form.

Methods: Chromatogram was run through Symmetry C18 (4.6 x 150mm, 5mm). Mobile phase containing 70% MeOH: 30% phosphate buffer pH 4.6 was pumped through column at a flow rate of 1 ml/min. Buffer used at pH 4.6. Temperature was maintained at Ambient. Optimized wavelength for Sulfamethoxazole and Trimethoprim was 273 nm.

Results:  Retention time of Sulfamethoxazole and Trimethoprim were found to be 2.003 min and 5.067 min. The % purity of Sulfamethoxazole and Trimethoprim was found to be 100.84 % and 100.29 % respectively. The system suitability parameters for Sulfamethoxazole and Trimethoprim such as theoretical plates and tailing factor were found to be 2711,1.6 and 3428, 1.3. the resolution was found to be 10.0. The linearity study for Sulfamethoxazole and Trimethoprim was found in concentration range of 25μg-125 μg and 25 μg-125 μg and correlation coefficient (r2) was found to be 0.999 and 0.999, % mean recovery was found to be 100.17 % and 100.24 %, %RSD for repeatability was 0.54 and 0.27 %. The precision study was precise, robust and repeatable. LOD value was 3.14 and 2.75, and LOQ value was 10.05 and 9.96 respectively.

Conclusion: The results of study showed that the proposed RP‐HPLC method is a simple, accurate, precise, rugged, robust, fast and reproducible, which may be useful for the routine estimation of Sulfamethoxazole and Trimethoprim in pharmaceutical dosage form.

Keywords: Sulfamethoxazole, Trimethoprim, RP‐HPLC, Simultaneous estimation