Pesticide analysis in tomatoes by solid-phase microextraction and micellar electrokinetic chromatography.
The analysis of a group of seven pesticides (i.e. six fungicides: pyrimethanil, procymidone, nuarimol, fenarimol, benalaxyl and penconazole and one insecticide: pirimicarb) in tomato samples by micellar electrokinetic chromatography is investigated. For this purpose, reversed electrode polarity stacking mode and solid-phase microextraction (SPME) have been used as on-line and off-line preconcentration procedures, respectively. Tomato samples were first homogenized and extracted with acetone. After suitable evaporation and reconstitution of the extract in water, a SPME procedure using poly(dimethylsiloxane)/divinylbenzene fibers was used. Due to the strong influence of the sample matrix in the extraction, a matrix matched calibration of spiked tomato samples was developed. The method was found to be linear between 0.5 and 2.5 mg/kg. Limits of detection achieved are below the maximum residue limits established by the European Union and Spain legislation as well as by the Codex Alimentarius (except for penconazole). The potential of the method was demonstrated by analyzing 12 tomato samples (of ecological and non-ecological production) taken from regional cultivars. No residues of the selected pesticides were detected in any of the samples.
Ravelo-Pérez
Lidia M
LM
Department of Analytical Chemistry, Nutrition and Food Science, University of La Laguna, Avenida Astrofísico Fco. Sánchez s/n, 38071 La Laguna, Tenerife, Canary Islands, Spain.
Hernández-Borges
Javier
J
Borges-Miquel
Teresa M
TM
Rodríguez-Delgado
Miguel Angel
MA
D020374:Chromatography, Micellar Electrokinetic Capillary / Q000379:methods*; D018551:Solanum lycopersicum / Q000737:chemistry*; D010573:Pesticide Residues / Q000032:analysis*; D011743:Pyrimidines / Q000032:analysis; D052617:Solid Phase Microextraction / Q000379:methods*; D014675:Vegetables / Q000737:chemistry
D010573:Pesticide Residues; D011743:Pyrimidines; C108337:pyrimethanil; C033789:fenarimol; C067672:nuarimol