title: Development and validation of a multiresidue method for the analysis of 151 pesticide residues in strawberry by gas chromatography coupled to a triple quadrupole mass analyzer.
abstract: A new method was developed and validated for the simultaneous determination of 151 pesticide residues in strawberry by gas chromatography coupled to a triple quadrupole mass analyzer (GC/QqQ-MS/MS), mainly using the selected reaction monitoring (SRM) mode. The list of target compounds included various classes of pesticides such as organochlorine (OCPs), organophosphorus (OPPs), carbamates, pyrethroids, triazoles and dicarboximides. A single extraction of 10 g of sample with acetonitrile followed by liquid-liquid partition formed by the addition of 4 g of MgSO4 and 1 g of NaCl was applied in sample preparation. Cleanup of the extracts was carried out by applying dispersive solid-phase extraction (D-SPE) with primary secondary amine (PSA). The analysis time was 21 min. The method was subjected to a thorough validation procedure. The recovery data were obtained by spiking blank samples at two concentration levels (11.5 and 50 microg/kg), yielding recoveries in the range 70-110%. Precision values expressed as relative standard deviation (RSD) were lower than 18% and 22% for the intraday and interday precision, respectively. Linearity was studied in the range 10-200 microg/kg and determination coefficients (R(2)) were higher than 0.98% for all compounds. Limits of detection (LODs) and limits of quantification (LOQs) were established as 4 and 10 microg/kg, respectively. The overall uncertainty of the method was estimated at two different concentrations (11.5 and 50 microg/kg), being lower than 25% in both cases. According to the validation data and performance characteristics as well as the high sample throughput and low cost, the proposed method is suitable for routine application.
authors.affiliation: Department of Analytical Chemistry, University of Almería, 04071 Almería, Spain.
authors.forename: Patricia Plaza
authors.initials: PP
authors.lastname: Bolaños
authors.forename: José Luis Fernández
authors.initials: JL
authors.lastname: Moreno
authors.forename: Deyana D
authors.initials: DD
authors.lastname: Shtereva
authors.forename: Antonia Garrido
authors.initials: AG
authors.lastname: Frenich
authors.forename: José Luis Martínez
authors.initials: JL
authors.lastname: Vidal
mesh_terms: D000465:Algorithms; D045424:Complex Mixtures / Q000032:analysis; D005504:Food Analysis / Q000379:methods*; D005506:Food Contamination / Q000032:analysis*; D031985:Fragaria / Q000737:chemistry*; D005638:Fruit / Q000737:chemistry*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D010575:Pesticides / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013048:Specimen Handling / Q000379:methods; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D045424:Complex Mixtures; D010575:Pesticides