Desenvolvimento e validação de método para determinação de resíduos de agrotóxicos organofosforados em sapoti (manilkara zapota) por CG-EM empregando QuEChERS

• Main Author: Alcântara, Daniel Barbosa
• Publication Date: 2016
• Format: Master thesis
• Language: por
• Source: Repositório Institucional da Universidade Federal do Ceará (UFC)
• dARK ID: ark:/83112/001300000mv4g
• Download full: http://www.repositorio.ufc.br/handle/riufc/35298
• topic: Sapoti; QuEChERS; CG-EM; Organofosforados

The development of analytical methods to monitoring pesticide residues in food is crucial to ensure that the concentration of these are within of the limits considered safe for health.This work describes an analytical methodology based in the QuEChERSsample preparation method and gas chromatography coupled to mass spectrometry for analysis of eight organophosphorus pesticides (dichlorvos, disulfoton, ethoprophos, methyl parathion, fenchlorphos, chlorpyrifos, methyl azinphos and prothiofos). As the sapodilla fruit has won the preference of brazilian consumers, presenting an expanding market, this matrix was used to the studs. The methodology was validated by evaluating the selectivity, linearity, limits of detection (LOD) and quantification (LOQ), precision and accuracy in terms of percentage of recovery.Statistical tests (t-student and F-Hartley) were applied toverify thesignificance of the parameters and the regression of analytical curves in sapodilla matrix. Due to the complexity of the sample, study the effect matrix was performed, where seven of the compounds evaluated had a positive effect matrix.All pesticides studied showed good linearity with correlation coefficient greater than 0.99.LODs and LOQs ranged from 0.01 to 0.07 mg kg-1 and 0.017 to 0.14 mg kg-1, respectively in the sapodilla matrix.Recovery studies with sapodilla samples spiked in six concentration levels (0.08, 0.10, 0.14, 0.17, 0.35 and 1.17 mg kg-1) showed satisfactory results (between 70 – 120% with RSD < 20%) in at least three levels of fortification (low, medium and high) for all pesticides.Analysis of commercial sapodilla samples revealed the presence of chlorpyrifos pesticide in 70.0% of the fruit samples and 33.3% of sapodilla pulps samples, even not permitted for use in sapodilla crops by brazilianagences– ANVISA.