Application of dispersive liquid-liquid microextraction for the analysis of organophosphorus pesticides in watermelon and cucumber.
In this article, a new method for the determination of organophosphorus pesticides (OPPs) in cucumber and watermelon was developed by using dispersive liquid-liquid microextraction (DLLME) and gas chromatography-flame photometric detection (GC-FPD). Acetonitrile (MeCN) was used as extraction solvent for the extraction of OPPs from plant samples. When the extraction process was finished, the target analytes in the extraction solvent were rapidly transferred from the MeCN extract to another small volume of organic solvent, chlorobenzene, using DLLME. Recovery tests were performed for concentrations between 0.5 and 20 microg/kg; recoveries for each target analyte were in the range between 67 and 111%. The repeatability of the proposed method, expressed as relative standard deviation, varied between 2 and 9% (n=3). Limits of detection of the method for watermelon and cucumber were found ranging from 0.010 to 0.190 microg/kg for all the target pesticides. Compared with the conventional sample preparation method, the proposed method has the advantage of being quick and easy to operate, and having high-enrichment factors and low consumption of organic solvent.
Zhao
Ercheng
E
Department of Applied Chemistry, China Agricultural University, 100094 Beijing, China.
Zhao
Wenting
W
Han
Lijun
L
Jiang
Shuren
S
Zhou
Zhiqiang
Z
D002623:Chemistry Techniques, Analytical / Q000379:methods*; D002722:Chlorobenzenes; D029773:Citrullus / Q000737:chemistry*; D018553:Cucumis sativus / Q000737:chemistry*; D009943:Organophosphorus Compounds / Q000032:analysis* / Q000302:isolation & purification; D010575:Pesticides / Q000032:analysis* / Q000302:isolation & purification; D012997:Solvents; D014867:Water
D002722:Chlorobenzenes; D009943:Organophosphorus Compounds; D010575:Pesticides; D012997:Solvents; D014867:Water; C031294:chlorobenzene