Validação de método analítico empregando QuEChERS e CG-EM para determinação multirresíduo de agrotóxico em goiaba

• Ano de defesa: 2014
• Autor(a) principal: Guedes, Jhonyson Arruda Carvalho
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Palavras-chave em Português: Agrotóxicos; Química analítica
• Link de acesso: http://www.repositorio.ufc.br/handle/riufc/15605

Guava is one of the most popular and widely accepted in Brazil and worldwide tropical fruits. The fruit can be targeted by various pests, reducing considerably the yield thus causing a slowdown or even a shortage of fruit on the market. Aiming the increase in productivity and ultimately the population's demand high amounts of pesticides are used in order to counter potential pests that may lead to a deterioration of the fruit. Thus, the development of analytical methods for multiresidue determination of pesticides in food is essential for the efficient monitoring of these compounds in the products consumed by the population, enabling regulators to obtain faster and more reliable results. In this work a method for the determination of pesticides in guava was developed and validated, running the sample preparation by modified QuEChERS method, replacing the acetonitrile solvent after cleaning step by cyclohexane / ethyl acetate solvent acetate 1:1 and addition of activated charcoal to extract greater cleanliness. The limits of detection (LOD) ranged between 0.002 and 0.010 mg kg -1 and the limits of quantification (LOQ) ranged from 0.005 to 0.030 mg kg-1 . All calibration curves constructed in solvent and in matrix showed statistical significance when compared to the analytical curves and a strong matrix effect for chlorobenzilate, unlike hexachlorobenzene and ametrina where the matrix effect was negligible. In the analyzes of samples of guava sold in the city of Fortaleza, pesticides were found in 7 samples. Pesticides detected, trifloxystrobin is only allowed for the cultivation of guava, however the concentration of this compound is below the maximum residue limit allowed for guava (MRL = 0.050 mg kg-1 ) according to ANVISA