US EPA

1129127 

Journal Article 

Determination of Two Pesticides in Soils by Dispersive Liquid-Liquid Microextraction Combined with LC-Fluorescence Detection 

Fu, LY; Liu, XJ; Hu, J; Zhao, XN; Wang, HL; Huang, CJ; Wang, XD 

2009 

Yes 

Chromatographia
ISSN: 0009-5893
EISSN: 1612-1112 

70 

11-12 

1697-1701 

English 

10.1365/s10337-009-1356-9 

WOS:000272173800026 

In the present work, a simple, rapid and sensitive sample pre-treatment technique, dispersive liquid-liquid microextraction (DLLME) coupled with liquid chromatography-fluorescence detection (LC-FLD), has been developed to determine carbamate (carbaryl) and organophosphorus (triazophos) pesticide residues in soil samples. Methanol was first used as extraction solvent for the extraction of pesticides from the soil samples and then as dispersive solvent in the DLLME procedure. Under the optimum extraction conditions, the linearity was obtained in the concentration range of 0.1-1,000 ng g(-1) for carbaryl and 1-5,000 ng g(-1) for triazophos, respectively. Correlation coefficients varied from 0.9997 to 0.9999. The limits of detection (LODs), based on signal-to-noise ratio (S/N) of 3, ranged from 14 to 110 pg g(-1). The relative standard deviation (RSDs, for 20.0 ng g(-1) of each pesticide) varied from 1.96 to 4.24% (n = 6). The relative recoveries of two pesticides from soil A1, A2 and A3 at spiking levels of 10.0, 20.0 and 50.0 ng g(-1) were in the range of 88.2-108.8%, 80.8-110.7% and 81.0-111.1%, respectively. The results demonstrated that DLLME was a sensitive and accurate method to determine the target pesticides, at trace levels, in soils. 

Dispersive liquid-liquid microextraction; Liquid chromatography-fluorescence detection; Organophosphate and carbamate in soil