Analysis of the Carbamate Insecticides Aldicarb and Carbaryl in Formulations Utilizing a High-Performance Liquid Chromatographic System with an On-Line Infrared Detector

Abstract

An aldicarb (2-methyl-2-(methylthio)propanal, o-[(methylamino)-carbonyl]oxime) granular formulation with and without added carbofuran (2, 3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate) as an internal standard and a carbaryl (1-naphthalenyl methylcarbamate) wettable powder and liquid suspension formulations both with and without added methiocarb (3,5-dimethyl-4-(methylthio)phenyl methylcarbamate) as an internal standard were analyzed by utilizing a high-performance liquid chromatographic system operating in the normal phase with a Partisil column and mixtures of acetonitrile:dichloromethane:heptane as the mobile phase. An on-line infrared detector equipped with a flowcell was used. Analyses were conducted at ambient temperature. The commonly used calibration and quantitation techniques were also compared.