Revisiting quick, easy, cheap, effective, rugged, and safe parameters for sample preparation in pesticide residue analysis of lettuce by liquid chromatography-tandem mass spectrometry

Autor(es)

Begnini Konatu, Fernanda Ribeiro ^[1] ; Breitkreitz, Marcia Cristina ^[1] ; Sales Fontes Jardim, Isabel Cristina ^[1]

Afiliação do(s) autor(es)

^[1] Univ Estadual Campinas, Inst Quim, Caixa Postal 6154, BR-13084971 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Chromatography A; v. 1482, p. 11-22, JAN 27 2017.
• Citações Web of Science: 14

Resumo

A new analytical method using a quick, easy, cheap, effective, rugged, and safe (QuEChERS) procedure for multi-residue determination of 16 multiclass pesticides in five different types of lettuce was developed using high-performance liquid chromatography coupled to electrospray ionization tandem mass spectrometry. The QuEChERS procedure was optimized in terms of extractor solvent, partitioning salts and clean-up salts, through recovery, gravimetric analysis and matrix-effect studies. Microwave extraction and the use of disposable pipette extraction in the clean-up step were also tested, providing interesting alternatives to the traditional QuEChERS method, depending on the pesticides properties. The use of a laboratory-made phenyl-type sorbent, based on silica and poly(2-phenylpropyl)methylsiloxane, was studied in the clean-up step, presenting promising results as a substitute for primary secondary amine (PSA). The optimized QuEChERS method was defined employing acetonitrile, citrate buffer and cleanup with PSA, MgSO4 and graphitized carbon black. The method developed was validated according to Document SANTE/11945/2015 and proved to be selective, accurate and precise, obtaining limits of quantification from 5 mu g kg(-1) and recoveries in the range of 70-120% with relative standard deviation <= 20%. The method was applied on 14 real samples from commercial markets in Brazil and 21% of the samples analyzed presented irregularities, according to local pesticides regulations. (C) 2016 Elsevier B.V. All rights reserved. (AU)

• Processo FAPESP: 11/23127-0 - Desenvolvimento e validação de métodos analíticos para determinação de multirresíduos de agrotóxicos em cultura de alface, por cromatografia líquida de ultra eficiência e cromatografia líquida acopladas à espectrometria de massas sequencial.
• Beneficiário: Fernanda Ribeiro Begnini Konatu
• Modalidade de apoio: Bolsas no Brasil - Doutorado