Enantiomeric separation of organophosphorus pesticidesby capillary electrophoresisApplication to the determination of malathion in water samplesafter preconcentration by off-line solid-phase extraction
The separation of the enantiomers of a group of organophosphorus pesticides (OPs) has been investigated by electrokinetic chromatography (EKC) using different anionic cyclodextrins as chiral selectors. The use of a 25mM Tris buffer (pH 7.0), 20mM in CM--CD together with an applied voltage of 24 kV a...
| Autores: | , , , , , |
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| Formato: | artículo |
| Estado: | Versión aceptada para publicación |
| Fecha de publicación: | 2005 |
| País: | España |
| Recursos: | Consejo Superior de Investigaciones Científicas (CSIC) |
| Repositorio: | DIGITAL.CSIC. Repositorio Institucional del CSIC |
| OAI Identifier: | oai:digital.csic.es:10261/346591 |
| Acesso em linha: | http://hdl.handle.net/10261/346591 |
| Access Level: | acceso abierto |
| Palavra-chave: | Enantiomeric separation organophosphorus pesticides Capillary electrophoresis Malathion Solid-phase extraction |
| Resumo: | The separation of the enantiomers of a group of organophosphorus pesticides (OPs) has been investigated by electrokinetic chromatography (EKC) using different anionic cyclodextrins as chiral selectors. The use of a 25mM Tris buffer (pH 7.0), 20mM in CM--CD together with an applied voltage of 24 kV and a temperature of 25 ¿C enabled the individual enantiomeric separation of malathion and phenthoate each one into its two enantiomers, the partial separation of the enantiomers of phenamiphos and the separation of three of the four enantiomers of isomalathion. Since naled is very reactive in aqueous solutions, its enantiomeric separation achieved in about 8 min in 25mM borate buffer at pH 9 with 10mM CM--CD resulted in the observation of a broad peak due to degradation products. A preconcentration step by disk solid-phase extraction was studied and used together with the chiral EKC method developed for the enantiomeric separation of malathion in order to determine this pesticide in tap water samples spiked at the gmL¿1 level. Finally, the precision and recovery of the method was established. |
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