Determination of the insecticide diflubenzuron in mushrooms by kinetic method and high-performance liquid chromatographic method

Abstract

In the present study, a new sensitive and simple kinetic-spectrophotometric method for the determination of the insecticide diflubenzuron [1-(4-chlorophenyl)-3-(2,6-diflubenzoil)urea] is proposed. The method is based on the inhibited effect of diflubenzuron on the oxidation of sulphanilic acid (SA) by hydrogen peroxide in phosphate buffer in presence Cu(II) ion. Diflubenzuron was determined with linear calibration graph in the interval from 0.31 to 3.1 μg mL⁻¹ and from 3.1 to 31.0 μg mL⁻¹. The optimized conditions yielded a theoretical detection limit of 0.18 μg mL⁻¹corresponding to 0.036 mg Kg⁻¹mushroom sample based on the 3S_b criterion. The RSD is 5.03–1.83 % and 2.81–0.71 % for the concentration interval of diflubenzuron 0.31–3.1 μg mL⁻¹and 3.1–31.0 μg mL⁻¹, respectively. The reaction was followed spectrophotometrically at 370 nm. The kinetic parameters of the reaction are reported, and the rate equations are suggested. The developed procedure was successfully applied to the rapid determination of diflubenzuron in spiked mushroom samples of different mushroom species. The HPLC method was used like a comparative method to verify results.

Keywords:

• Diflubenzuron
• kinetic method
• HPLC method
• liquid-liquid extraction
• mushrooms

Acknowledgment

This research was supported by grant number 142015 from the Serbian Ministry of Science. The authors are grateful for the financial support provided by this Ministry.