N. Font et al., MICROWAVE-ASSISTED SOLVENT-EXTRACTION AND REVERSED-PHASE LIQUID-CHROMATOGRAPHY UV DETECTION FOR SCREENING SOILS FOR SULFONYLUREA HERBICIDES, Journal of chromatography, 798(1-2), 1998, pp. 179-186
Citations number
26
Categorie Soggetti
Chemistry Analytical","Biochemical Research Methods
A multi-residue method for the rapid assay of cinosulfuron, thifensulf
uron-methyl, metsulfuron-methyl, sulfometuron-methyl and chlorsulfuron
in soil samples has been developed. The method involves microwave-ass
isted solvent extraction (MASE) prior to analysis by reversed-phase li
quid chromatography (RPLC) and UV detection at 226 nm. MASE conditions
were established providing efficient extraction without degradation o
f the analytes, furthermore selectivity can be enhanced by limiting th
e coextraction of interferences. Selected MASE conditions, including d
ichloromethane-methanol (90:10,v/v) as the extraction solvent, provide
d, in 10 min, a complete extraction of the analytes from soil samples.
The extracts obtained with the developed MASE procedure are analysed
by RPLC-UV in less than 15 min without additional cleanup; the overall
procedure allows the determination of the analytes in soils to a leve
l of at least 5 mu g/kg. Method validation was performed by analysing
freshly spiked sail samples and samples with aged residues at levels b
etween 20 and 1000 mu g/kg. Depending on the spiked level and the type
of spiked sample recoveries were obtained between 70-100% with R.S.D.
s between 1-10%. (C) 1998 Elsevier Science B.V.