Avaliação de biocarvões na miniaturização da MSPD para determinação de resíduos de pesticidas em alimentos para bebês

Abstract

Commercially available foods based on fruits, vegetables, meat and cereals are offered to babies from the age of six months chemical such as pesticides are used in crop cultivation to boost production meeting market demand and controlling pests that hinder plant and fruit growth. Residues of these compounds can remain in the final product and potentially affect a baby’s health; consequently, analytical methods are developed to detect contaminants in various samples. The use of miniaturized methods emerged as a way to reduce solvent volume and the amounts of adsorbents, as well as to eliminate steps compared to conventional method. Thus, this study aimed to develop a miniaturized MSPD method using pipette tips to extract the pesticides abamectin, acephate, acetamiprid, azoxystrobin, bifenthrin, clothianidin, difenoconazole, dimethoate, epoxiconazole, flutriafol, imidacloprid, lufenuron, malathion, methomyl, permethrin, pyraclostrobin, teflubenzuron, thiacloprid, thiamethoxam and thiophanate – methyl from pasty baby foods, in conjunction with liquid chromatography and DAD/UV-Vis detection. Commercial adsorbents C18, sílica gel, PSA, florisil, neutral alumina and the synthetic adsorbent TEOS were tested, as were solventes including methanol, acetonitrile, and mixtures with dichloromethane and ethyl acetate, evaluated at various volumes and ratios. The optimal extraction conditions involved using 40 mg of sample (fortified at 1 µg mL 1 ), 60 mg of sílica gel and 1000 µL of MeOH:ethyl acetate (50:50 v,v), yielding recoveries between 70 – 108 %. Subsequently, the parameters of the sample preparation method using corn cob biochar the adsorbent material that proved most efficient for analyte extraction under the same conditions previously established for sílica, but employing MeOH for analyte elution recovery rates ranged from 62 % to 112 %. Finally, the two methods developed in this study were validated by evaluating the parameters of linearity, sensitivity, selectivity, limit of detection, limit of quantification, accuracy, and precision. Subsequently, the methods were applied to samples of different brands and compositions marketed in Sergipe, but the pesticides under study were not found.