Comparison of Liquid Chromatography–Atmospheric Pressure Chemical Ionization/Mass Spectrometry and Liquid Chromatography–Postcolumn Fluorometry for Determination of Carbamates in Food

Abstract

Abstract Two detection methods, postcolumn derivatization with fluorescent detection and atmospheric pressure chemical ionization/mass spectrometry (MS) were compared for determination of N-methyl carbamates in food by liquid chromatography. Five commodities were spiked with 11 carbamates at levels from 10 to 100 ppb, extracted, and cleaned up by using a method based on the AOAC official method. With each detection method, sample blanks showed false-positive responses, indicating that neither method alone provides definitive identification. Except for aldicarb sulfoxide determined by MS, recoveries were linear between 10 and 100 ppb. Agreement between the 2 methods was good for determination of recoveries at 25 ppb. Coefficients of variation were 11–33% for fluorescence detection and 9–26% for MS.