Puangkaew Lakkanatinaporn and Chutima Matayatsuk

pp. 849 - 854

Abstract

A simple HPLC method has been developed for the separation and determination of sodium trimethoprim phenylpropanol disulphonate and sodium sulfaquinoxaline in veterinary preparations. Both
drugs were separated well on a Kromasil C₁₈ column (5 µm, 150 × 4.6 mm) using a mixture of acetonitrile
and 0.5% triethylamine in 1% acetic acid, pH 3 (18:82, v/v) as the mobile phase at the flow rate of 1.5 ml/
min. The presence of both substances was monitored by UV absorption detection at 271 nm. The retention
times of sodium trimethoprim phenylpropanol disulphonate and sodium sulfaquinoxaline were 3.2 and 16.0
min, respectively. The performance of the developed method was tested. Linear responses of both drugs were
achieved between 48-145% of labeled amount over the concentration ranges of 35-101 µg/ml and 102-306 µg/
ml for sodium trimethoprim phenylpropanol disulphonate and sodium sulfaquinoxaline with correlation
coefficients (R²) of 0.9980 and 0.9998, respectively. Accuracy expressed in term of recoveries were 101.4±
1.21% (n=6) for sodium trimethoprim phenylpropanol disulphonate and 99.7±0.92% (n=6) for sodium
sulfaquinoxaline. Precision of the method in terms of the relative standard deviation is not more than 2% in
all cases. These figures of merit indicated the validity of the developed method.