According to results of the Program of Analysis of Pesticide Residues in Foods of the National Agency of Sanitary in Brazil (2013 to 2015) the zucchini, Cucurbita pepo L is one of the non-hardy vegetables, that presented higher contamination index by pesticides residues. One of these agrochemicals is carbofuran, which although not authorized for this crop, is commonly and illegally used for whitefly control. The objective of this study was to optimize the solid-liquid extraction method with low temperature partitioning (SLE/LTP) for the determination of carbofuran residues in zucchini by high performance liquid chromatography with ultraviolet detector (HPLC-UV). The optimization was performed with a complete factorial design, 2³ to evaluate the simultaneous performance of three factors in two levels, in triplicate. The optimized SLE/LTP-HPLC/UV method showed to be selective, simple and efficient, consuming a small amount of sample and solvent extractor. The average recovery percentage was 75.88%. Samples of zucchini purchased in the Itumbiara-GO trade, Brazil, and submitted to the optimized method did not present carbofuran residues.

Carbamatos são os pesticidas mais frequentemente encontrados em alimentos e bebidas de coloração escura em casos de intoxicação acidental ou intencional. Neste trabalho, extração líquido-líquido com partição em baixa temperatura (LLE-LTP) foi otimizada e validada para determinação dos carbamatos aldicarb, carbofuran e carbaril em bebidas de sucos de uva e leite achocolatado. Este método envolve a extração com acetonitrila, partição líquido-líquido em baixa temperatura e análise por cromatografia líquida de alta eficiência com detecção ultravioleta (HPLC-UV). O método é rápido, eficiente e de baixo custo, emprega pequenos volumes de solvente por amostra e não necessita de limpeza dos extratos. O método de extração foi seletivo e apresentou porcentagens de extração acima de 90%. As premissas relacionadas com os testes estatísticos de linearidade foram verificadas e confirmadas. O método de extração e análise foi validado com resultados satisfatórios e pode ser aplicado em análises de rotina e forenses.

Carbamates are the pesticides most commonly found in dark colored foods and beverages in cases of accidental or intentional poisoning. In this work, the liquid-liquid extraction with low temperature partitioning (LLE-LTP) was optimized and validated for determination of the carbamates aldicarb, carbofuran and carbaryl in grape juice and chocolate milk beverages. This method involved extraction with acetonitrile, liquid-liquid partition at low temperature and the analysis by high performance liquid chromatography with ultraviolet detection (HPLC-UV). The method is rapid, efficient and of low-cost, employing small volumes of solvent per sample and requiring no cleanup of the extracts. The extraction methodology was selective and presented recovery percentages above 90%. The premises related to the statistical linearity tests were checked and confirmed. The method of extraction and analysis was validated with satisfactory results, and may be applied in forensic and routine analysis.