Analysis of N-methylcarbamates insecticides and some of their main metabolites in urine with liquid chromatography using diode array detection adn electrospray mass spectrtometry

摘要

Commonly used N-methylcarbamates,i.e.,aldicarb and carbofuran and some of their main metabolites as aldicarb sulphoxide and aldicarb sulphone for aldicarb and 3-hydroxycarbofuran for carbofuran were extracted from human urine by off-line solid phase extraction with graphite carbonandsubsequently clean up with NH_2-modified silica.Analyte fractionation and quantification wereperformed by liquid chromatography (LC)with UV detection.The revovery efficiencies of the tested compounds yielded more than 81% at the fortification level of 0.05 #mu#g/ml in urine and their relative standard deviations were between 6 and 16%.The detection limits of each compound ranged between 4 and 10 #mu#g/l.This method involves confirmatory analysis by LC-electrospray mass spectrometry(MS)instrumentation equipped with a single quadrupole mass filter.MS data acquisition was performed by time-scheduled selected ion monitoring (SIM)program.Limits of detection giving values between 0.1 and 0.5#mu#g/l.Urine samples froma pest control operator were analyzed and the analytes were not found.