DETERMINATION OF CARBENDAZIM IN VEGETABLE AND SOIL SAMPLES BASED ON INCLUSION COMPLEX AND FLUORESCENCE SPECTROSCOPY

摘要

Carbendazim is one of the most active pesticide compounds of benzimidazole fungicides which have both protective and curative activities against a wide range of fungal diseases in crops. Widespread use of pesticide in agricultural production leads to excessive pesticide residues. Pesticide residue problems have become increasingly prominent and caused widespread concern around the world. In this work, a kind of β-cyclodextrin/4,4’-diaminobiphenyl (CDBD) fluorescent derivative was prepared with 4,4'-diaminobiphenyl, β-cyclodextrin (β-CD) and 4- toluene sulfonyl chloride as raw materials. The structure of CDBD was characterized by elemental analysis, fourier transform infrared spectra (FT-IR) and 1 H NMR and scanning electron microscope (SEM). An inclusion complex between CDBD and the carbendazim was formed and characterized by transmission electron microscopy (TEM) and X-ray diffraction (XRD); and the binding constant () of the inclusion complex was investigated. The effects of surfactant and pH value on the fluorescence spectra of the system were studied; and the inclusion complex could be applied to determination of carbendazim residues. Based on the enhancement of the fluorescence intensity of carbendazim produced through complex formation, a sensitive method for the determination of carbendazim was established. A linear relationship was obtained between the fluorescence intensity and carbendazim concentration in the range of 0 and 66.92 μg L-1 with a correlation coefficient of 0.9952. The limit of detection (LOD) and the relative standard deviation (RSD) were 1.26 ng L-1 and 0.079, respectively. The proposed method has better anti-interference ability and stability, and has been successfully applied to the determination of carbendazim in vegetable and water samples with satisfactory results; recoveries in the range of 98.2 to 101.1 were obtained. The method is rapid, simple, direct, economical, sensitive and useful for carbendazim analysis.