DEVELOPMENT AND VALIDATION OF KINETIC SPECTROPHOTOMETRIC METHOD FOR HERBICIDE BROMFENOXIM DETERMINATION

Abstract

A kinetic spectrophotometric method for determining the residues of herbicide bromofenoxim (BrFX) has been developed and validated. The proposed method is based on the inhibitory effect of BrFX on the oxidation of sulfanilic acid (SA) by hydrogen peroxide in the presence of Cu(II) ion, which was monitored at 370 nm. The variables affecting the rate of the reaction were investigated and the optimum conditions were established. BrFX can be measured in the range of 0.041 – 0.46 μg/ml and 0.46 – 13.86 μg/ml. The detection limit of the method with 3σ criteria is 0.0077 μg/ml. The relative standard deviations for five replicate determinations of 0.041, 0.24 and 0.46 μg/ml BrFX are 3.0, 5.32 and 2.85%, respectively. This method can be successfully used to determine BrFX concentration in baby juice samples. The HPLC method is used to verify the results. The results obtained for the same samples by the two methods are quite comparable.