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Determination of carbaryl, carbofuran and methiocarb in cucumbers and strawberries by monoclonal enzyme immunoassays and high-performance liquid chromatography with fluorescence detection: An analytical comparison

Laboratorio Integrado de Bioingenierı́a, Universidad Politécnica de Valencia, Camino de Vera s/n, 46022 Valencia, Spain
Journal of Chromatography A (Impact Factor: 4.26). 03/1999; DOI: 10.1016/S0021-9673(98)00856-5

ABSTRACT Carbaryl, carbofuran and methiocarb are three of the most important N-methylcarbamate pesticides. In the present work, the application of laboratory-developed monoclonal antibody-based enzyme-linked immunosorbent assays (ELISAs) to the determination of these compounds in fruits and vegetables is described. Cucumbers and strawberries were spiked with the three carbamates at 10, 50 and 200 ppb. After extraction and clean-up, samples were analyzed by immunoassay and by HPLC with post-column derivatization and fluorescence detection (US Environmental Protection Agency Method 531.1). Results obtained by ELISA correlated well with those obtained by HPLC, both in terms of accuracy and precision. Recoveries were in the 60–90% range by ELISA and in the 50–90% range by HPLC, depending on the particular combination of commodity, pesticide, and fortification level under consideration. ELISAs were also applied to the analysis of non-purified sample extracts with excellent results: recoveries close to 100% were obtained, while maintaining similar precision values. This approach avoids the use of solid-phase extraction columns, saves time, and considerably increases the sample throughput. Results clearly indicate that the developed immunoassays may be suitable for the quantitative and reliable determination of carbaryl, carbofuran and methiocarb in fruits and vegetables even without including clean-up steps. These considerations make these ELISAs very useful analytical tools for monitoring and regulatory programs, without the need of complex and expensive instrumentation.

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    • "Many countries have developed programmes for pesticides monitoring, including the U.S. Environmental Protection Agency (EPA) that established the use of HPLC with a postcolumn derivatization and fluorescence for detection of carbaryl. Although this method is sensitive and well established, its regular use remains complex and expensive instrumentation is required [3] [4]. Electrochemical methods, including the use of amperometric biosensors, on the other hand, are simple, inexpensive and highly sensitive methods [5] [6]. "
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    • "Immunoassays, especially the enzyme-linked immunosorbent assay (ELISA), have been emerging as an attractive alternative to the traditional chromatographic methods. [1] [2] Due to their simplicity and cost-effectiveness, immunoassays can be used for the high sample throughput and on-site screening of pesticide residue. [3] [4] A successful immunoassay for detection of pesticide residue requires the production of antibodies against the targeted pesticide molecule. "
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