PW11 Chiral Chemistry: Catching Pollutants Right-handed!
Exhibit Hall
8:00 AM - Wednesday, 12 November 2003
(PW186) The role of chirality in the degradation of metolachlor and enantiomeric conversion.
Aga, D1, Klein, C1, 1 University at Buffalo, Buffalo, NY, US
ABSTRACT- Metolachlor is an herbicide used in controlling broadleaf weed growth and is applied to agricultural areas across the United States. After application, metolachlor can degrade into highly soluble oxanilic acid (OXA) and ethanesulfonic acid (ESA) metabolites, which are highly soluble in the environment. Metolachlor and its metabolites consist of two pairs of enantiomers, with the S-enantiomer being the herbicidally active isomer. We will present the results of our study to investigate the role of chirality in the rate of degradation of metolachlor and the formation of metabolites under controlled systems. Chiral separation of OXA and ESA was achieved using capillary zone electrophoresis with UV detection and a buffer of 50mM sodium borate at a pH of 9.0, 25mM sodium dodecyl sulfate, 15% methanol (v/v) and 2.6% gamma cyclodextrin (w/w). Metolachlor was separated using an HPLC chiral column. This study will show whether or not there is an enantioselective degradation of metolachlor in soil and if this is affected by corn vegetation.
Key words: chiral, metolachlor, degradation, enantiomer