Linked Life Data

17955985

Source:http://linkedlifedata.com/resource/pubmed/id/17955985

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PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2007-10-24
pubmed:abstractText
A simple and sensitive method using high-performance liquid chromatography/ mass spectrometry (LC/MS) was developed and validated for simultaneous determination of 5 benzoylurea insecticides-diflubenzuron, triflumuron, teflubenzuron, lufenuron, and flufenoxuron-in tomatoes. Residues were successfully separated on a C18 column by methanol-water isocratic elution. Detection was carried out by an ultraviolet diode array detector (UV-DAD) coupled with a quadrupole mass spectrometer, using atmospheric pressure chemical ionization (APCI) in negative-ion mode. The main ions were the deprotonated molecules [M-H]- for triflumuron, and the anions formed by elimination of hydrofluoric acid [M-H-HF]- for diflubenzuron and flufenoxuron, and [M-2H-HF] for lufenuron and teflubenzuron. The calibration plots were linear for both detectors over the range 0.05 to 10 microg/mL, and the method presented good quality parameters. The limits of detection for standard solutions were 0.008-0.01 mg/L (equivalent to 0.08-0.1 ng injected) for both detectors, and the limits of quantification (LOQs) were approximately 10 times lower than national maximum residue levels (MRLs). Depending on the compound and the detector, the LOQ values ranged from 0.2 to 0.4 ng injected. The optimum LC-UV-DAD/APCI-MS conditions were applied to the analysis of benzoylureas in tomatoes. The obtained recoveries from fortified tomato samples (50 g), extracted with ethyl acetate and purified by solid-phase extraction on silica sorbent, were 88-100 and 92.9-105% for the UV-DAD and MS detectors, respectively, with precision values (relative standard deviations) of 2.9-11 and 3.7-14%, respectively. The method was applied to 12 tomato samples from local markets, and diflubenzuron and lufenuron were detected in only one sample at concentrations lower than the MRLs. The results indicate that the developed LC/MS method is accurate, precise, and sensitive for quantitative and qualitative analysis at low levels of benzoylureas required by legislation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
1060-3271
pubmed:author
pubmed:issnType
Print
pubmed:volume
90
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1395-401
pubmed:dateRevised
2008-3-17
pubmed:meshHeading
pubmed:articleTitle
Determination of benzoylurea insecticide residues in tomatoes by high-performance liquid chromatography with ultraviolet-diode array and atmospheric pressure chemical ionization-mass spectrometry detection.
pubmed:affiliation
Agricultural University of Athens, Laboratory of Pesticide Science, Votanikos, 118 55 Athens, Greece. markan@aua.gr
pubmed:publicationType
Journal Article