Development of a Supercritical Fluid Extraction method for simultaneous determination of organophosphorus, organohalogen, organonitrogen and pyretroids pesticides in fruit and vegetables and its comparison with a conventional method by GC-ECD and GC-MS

Abstract

O presente trabalho tem como objetivo aplicar uma metodologia multiresíduo visando a determinação de pesticidas em frutas e vegetais, utilizando extração com fluido supercrítico e análise por cromatografia gasosa e detector por captura de elétrons e espectrometria de massas. Um método convencional por extração sólido-líquido baseado na literatura e um método com fluido supercrítico desenvolvido, foram aplicados na determinação simultânea de 32 pesticidas de 4 classes diferentes (organoclorados, organonitrogenados, organofosforados e piretróides) em amostras de alface, batata, maçã e tomate. As recuperações obtidas para a maioria dos pesticidas foram de 74% a 96% para ambos os métodos em níveis entre 0,04 -0,10 mg kg -1 , os limites de quantificação (dependendo da matriz e do pesticida) foram menores que 0,01 mg kg -1. SFE mostrou-se vantajosa quando comparada à extração sólido-líquido como economia de solventes, tempo e custos, podendo ser aplicada no monitoramento de pesticidas em alimentos.The aim of this paper was to apply a multiresidue method using Supercritical Fluid Extraction (SFE) and capillary gas chromatography with electron capture and mass spectrometry detections in the analysis of the levels of pesticide residues in fruits and vegetables. Single laboratory validation of both solid-liquid and supercritical fluid extraction methods was carried out for 32 compounds selected from four pesticide classes (organochlorine, organonitrogen, organophosphorus and pyretroid) in blank and fortified samples of fresh lettuce, potato, apple and tomato. Recoveries for the majority of pesticides from fortified samples at fortification level of 0.04-0.10 mg kg -1 ranged 74-96% for both methods and confirmation of pesticide identity was performed by gas-chromatographymass spectrometry in a selected-ion monitoring mode. Both methods showed good limits of detection (less 0.01 mg kg -1 , depending on the pesticide and matrix) and the SFE method minimized environmental concerns, time, and laboratory work.

Evaluation of the performance of a castor-oil based formulation in limiting pesticide residues in strawberry crops

“…22,23 A 50 g portion of the homogenate strawberry sample was extracted with 80 mL of acetone in an ultrasonic bath for 20 min and then vacuum-filtered through a Buchner funnel. A volume of 25 mL of saturated NaCl solution and 250 mL of distilled water were added to the filtrate, followed by liquid-liquid partitioning with 2 x 50 mL of dichloromethane.…”

Decontamination of hazardous substances from solid matrices and liquids using supercritical fluids extraction: A review

“…To date, SFE has also been regarded as an efficient and rapid method for the isolation of hazardous compounds from various kinds of plant matrices. Studies on the removal or analysis of hazardous compounds (pesticides and herbicides) from various kinds of plants matrices have been conducted by many authors [131][132][133][134][135][136][137][138][139][140][141][142][143][144] and a brief description of their studies is outlined in Table 4.…”

Determination of pesticide residues in tomato using dispersive solid-phase extraction and gas chromatography/ion trap mass spectrometry

“…2,[7][8][9] Besides, a relatively low number of samples above the MRL were found in studies of real samples collected in local markets. 10,11 In 2003, Anastassiades, Lehotay, Štajnbaher, & Schenck introduced a sample preparation method named QuEChERS (quick, easy, cheap, effective, rugged and safe) involving pesticide dispersive solid phase extraction (dSPE), with primary secondary amine (PSA) sorbent. Compared to other procedures, the QuEChERS method is very fast and cheap.…”