Herbicide analysis by micellar electrokinetic capillary chromatography

Abstract

Capillary electrophoresis with ultraviolet detection (CE-UV) and laser-induced fluorescence detection (CE-LIF) was used for analysis of a group of herbicides that have widespread use in the USA. CE-UV was employed for simultaneous determination of atrazine, simazine, alachlor and metolachlor in water. In addition, CE-UV was also suitable for analysis of dicamba, 2,4-D and chlorimuron ethyl. Dicamba, 2,4-D and chlorimuron ethyl were also analyzed using CE-LIF following derivatization with fluorescent reagents. Dicamba and 2,4-D were derivatized with 4-bromomethyl-7-methoxycoumarin and chlorimuron ethyl was derivatized with dansyl chloride following hydrolysis. The detection limit with CE-UV for atrazine, simazine and metolachlor was 0.1 μg/l and for alachlor was 1.0 μg/l. The estimated detection limit with CE-LIF for dicamba, 2,4-D and chlorimuron ethyl was 10 ng/l. Our results demonstrate that CE provides a powerful new analytical tool for herbicide analysis.