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Carbofuran (Carbofuran, 2,3 - dihydro-2 ,2 - dimethyl-7 - benzofuranyl-N-methyl carbamate), scientific name carbofuran, since 1969 by the FMC Corporation and Mobay development and production of chemical company as soon as an efficient, broad-spectrum pesticides, widely used in food, vegetables and fruits such as pest control. Carbofuran vivo cholinesterase with irreversible binding, thereby inhibiting its activity, the accumulation of acetylcholine in the tissue and cause poisoning. Carbofuran residues in soil degradation is not easy, longer half-life, its degradation desired 3 - hydroxy-carbofuran toxic than carbofuran, easy to cause environmental pollution. National standards for pesticide residues in food has been specified and vegetables may not be detected, but the phenomenon of illegal use is still serious, fruit and vegetable exports of agricultural products to cause serious economic losses. Therefore, a rapid and sensitive detection method for strengthening food safety monitoring and protecting the environment is important. In this study, carbofuran, p-nitrophenyl chloroformate and 6 - aminocaproic acid as raw materials, to avoid the traditional chemical synthesis process triphosgene, synthetic hapten carbofuran: 6 - [[(2,3 - dihydro- -2,2 - dimethyl-7 - benzofuranyl) carbonyl] amino] hexanoic acid (BFNH). Hapten carrier protein (BSA, OVA) conjugated carbofuran artificial antigens prepared BSA-BFNH and coating antigen OVA-BFNH. Use BFNH-BSA immunized rabbit polyclonal antibody access to anti-carbofuran, and through indirect ELISA antibody titer. The results showed that rabbit antiserum titer reached 1.28 × 10 6 . According phalanx titration best working concentration of antigen-antibody screening, when OD 450 around 1.0, the coating antigen concentration of 0.25μg · mL -1 , an anti-dilution was 1:1.6 × 10 5 , goat anti-rabbit IgG-HRP diluted 1:10 4 -fold, as the concentration of the experimental work best. Using octanoic acid - ammonium sulfate precipitation purified antibodies, purified antibody titer reached 1.024 × 10 7 , concentrated antibody protein concentration was 40mg · mL -1 , after 10 % SDS-PAGE analysis of heavy and light chain molecular weight of about 55kDa and 22kDa. Measured by indirect competitive ELISA inhibition with different concentrations of the standard rate of carbofuran, carbofuran standard curve produced using the software Origin7.5 linear regression analysis. In 10 -7 ~ 0.01mg · mL -1 range, the inhibition rate with the standard linear relationship between the concentration of pesticides significantly, y = 27.13 3.54X (R = 0.9971), The detection limit was 10 -7 mg · mL -1 , with five structurally similar carbamate cross-reactivity rate of less than 10%. Developed for the rapid detection of carbofuran residues in Zizania head ELISA kit used in the sample for the rapid detection of carbofuran residues, suggesting that large numbers of samples for rapid screening.
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