title: Multiresidue method for the fast determination of pesticides in nutraceutical products (Camellia sinensis) by GC coupled to triple quadrupole MS.
abstract: A method based on QuEChERS (quick, easy, cheap, effective, rugged, and safe) has been developed and validated for the determination and quantification of more than 140 pesticides in nutraceutical products obtained from green tea (Camellia sinensis). Extraction was performed with acidified acetonitrile (acetic acid 1%, v/v) and a clean-up step using primary secondary amine (50 mg), graphitized black carbon (100 mg) and magnesium sulfate (200 mg) was needed. Pesticide determination was achieved utilizing GC coupled to triple quadrupole MS/MS using the selective-reaction monitoring mode. The total run time was 23 min. Pesticides were quantified using matrix-matched calibration. Recoveries ranged from 70 to 120% and relative SD was lower than 25% at 10, 50, and 100 μg/kg. LOQs were lower than 10 μg/kg. 148 pesticides were validated. The validated method was applied to commercial nutraceutical products, detecting 4,4-dichlorobenzophenone (28 μg/kg), o,p'-dicofol (38 μg/kg) and p,p-dicofol (44 μg/kg) in a few samples.
authors.affiliation: Research Group "Analytical Chemistry of Contaminants," Department of Chemistry and Physics, Research Centre for Agricultural and Food Biotechnology (BITAL), University of Almería, Agrifood Campus of International Excellence, ceiA3, Almería, Spain.
authors.forename: Gerardo
authors.initials: G
authors.lastname: Martínez-Domínguez
authors.forename: Patricia
authors.initials: P
authors.lastname: Plaza-Bolaños
authors.forename: Roberto
authors.initials: R
authors.lastname: Romero-González
authors.forename: Antonia Garrido
authors.initials: AG
authors.lastname: Frenich
mesh_terms: D028241:Camellia sinensis / Q000737:chemistry*; D019587:Dietary Supplements / Q000032:analysis*; D005506:Food Contamination / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry; D010575:Pesticides / Q000032:analysis*
chemical_list: D010575:Pesticides
keywords: GC-tandem MS; Green tea; Nutraceuticals; Pesticide residues; QuEChERS