RESUMO
The development of a direct competitive enzyme-linked immunosorbent assay based on polyclonal antibodies for N-methylcarbamate insecticide metolcarb is described. Two new haptens for the metolcarb were designed and synthesized. Both haptens were conjugated with keyhole limpet hemocyanin to form the immunogens. Four rabbits were immunized with the immunogens for production of polyclonal antibodies against metolcarb. Antisera titers were tested on the homologous coating antigens using a noncompetitive indirect enzyme-linked immunosorbent assay. The high titer antisera were used to develop the direct competitive enzyme-linked immunosorbent assay for the detection of metolcarb. The antibody-antigen combination with the highest selectivity for metolcarb was further optimized and its tolerance to changes in chemical conditions (ionic strength, pH value, and organic solvent) was studied. Under optimum conditions, the sensitivity and the limit of detection were determined to be 22 microg L(-1) and 1.2 microg L(-1) respectively. Determination of metolcarb in fruit juices and vegetables was accomplished by simple, rapid, and efficient extraction methods. Recoveries of metolcarb from spiked samples ranged from 80.5% to 109.5%. Validation of the developed immunosorbent assay was conducted by comparison of results from high-performance liquid chromatography. The correlation between the data obtained using developed immunosorbent assay and high-performance liquid chromatography was high (R2 = 0.9884). Therefore, the developed immunosorbent assay in this study was suitable for the rapid quantitative determination of metolcarb in agricultural products.
Assuntos
Bebidas/análise , Ensaio de Imunoadsorção Enzimática/métodos , Contaminação de Alimentos/análise , Resíduos de Praguicidas/análise , Fenilcarbamatos/análise , Verduras/química , Animais , Anticorpos/imunologia , Ensaio de Imunoadsorção Enzimática/economia , Haptenos/química , Haptenos/imunologia , Soros Imunes/imunologia , Resíduos de Praguicidas/imunologia , Fenilcarbamatos/imunologia , Sensibilidade e Especificidade , Fatores de TempoAssuntos
Inibidores da Colinesterase/efeitos adversos , Dessensibilização Imunológica , Hipersensibilidade a Drogas/prevenção & controle , Exantema/induzido quimicamente , Hipersensibilidade Tardia/induzido quimicamente , Fenilcarbamatos/efeitos adversos , Administração Cutânea , Idoso de 80 Anos ou mais , Doença de Alzheimer/tratamento farmacológico , Inibidores da Colinesterase/administração & dosagem , Inibidores da Colinesterase/imunologia , Hipersensibilidade a Drogas/etiologia , Exantema/prevenção & controle , Feminino , Humanos , Fenilcarbamatos/administração & dosagem , Fenilcarbamatos/imunologia , Rivastigmina , Testes CutâneosRESUMO
A direct competitive enzyme linked immunosorbent assay in multi-enzyme tracers format for the simultaneous analysis of carbaryl and metolcarb in agricultural products is described in this study. The concentrations of coating antibodies and enzyme tracer were studied. Under the optimum conditions, the limits of detection of carbaryl and metolcarb were 0.15 microg L(-1) and 1.2 microg L(-1), respectively. Determination of carbaryl and metolcarb in fruit juices and vegetables was accomplished by simple, rapid and efficient extraction methods. Recoveries of spiked samples were great than 70%. Validation of the immunosorbent assay was conducted by comparison of results from high performance liquid chromatography (HPLC). The correlations between the data obtained using multi-enzyme tracers enzyme linked immunosorbent assay and high performance liquid chromatography were good. Results indicated that the new strategy for developing immunoassay for simultaneous quantitative determination of carbaryl and metolcarb residues was suitable in this study.