title: Dispersive liquid-liquid microextraction using non-chlorinated, lighter than water solvents for gas chromatography-mass spectrometry determination of fungicides in wine.
abstract: A novel and low solvent consumption method for the sensitive determination of fungicide residues in wine samples is proposed. Analytes were extracted by dispersive liquid-liquid microextraction (DLLME) and further determined by gas chromatography-mass spectrometry (GC-MS). Under optimized conditions, a binary mixture of acetone and 1-undecanol (0.5 and 0.05 mL, respectively) was used to extract target compounds from diluted (1:1) wine samples. After centrifugation, the floating phase of 1-undecanol was solidified and separated from the liquid hydro-alcoholic matrix. Thereafter, it was allowed to melt at room temperature and injected in the GC-MS system. The method showed relative standard deviations (RSDs, %) below 13%, limits of quantification (LOQs) between 0.2 and 3.2 ng mL(-1) and linear responses for concentrations up to 300 ng mL(-1). The efficiency of the liquid-phase microextraction process was scarcely affected by the characteristics of wine samples, consequently pseudo-external standard calibration (using matrix matched standards of red and white wine) sufficed to achieve acceptable accuracy values: relative recoveries from 81 to 120%. The applicability of the method was demonstrated with commercial wine samples.
authors.affiliation: Departamento de Química Analítica, Nutrición y Bromatología, Instituto de Investigación y Análisis Alimentario, Universidad de Santiago de Compostela, Santiago de Compostela 15782, Spain.
authors.forename: T
authors.initials: T
authors.lastname: Rodríguez-Cabo
authors.forename: I
authors.initials: I
authors.lastname: Rodríguez
authors.forename: M
authors.initials: M
authors.lastname: Ramil
authors.forename: R
authors.initials: R
authors.lastname: Cela
mesh_terms: D005591:Chemical Fractionation / Q000295:instrumentation / Q000379:methods*; D004350:Drug Residues / Q000032:analysis / Q000302:isolation & purification*; D005506:Food Contamination / Q000032:analysis; D005659:Fungicides, Industrial / Q000032:analysis / Q000302:isolation & purification*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D012680:Sensitivity and Specificity; D014920:Wine / Q000032:analysis*
chemical_list: D005659:Fungicides, Industrial