Single drop microextraction: a sensitive multiresidue method for determination of pesticides in water using GC/ECD

• Autor(a) principal: Soares,Carlos E. S.
• Data de Publicação: 2014
• Outros Autores: Neves,Antônio A., Queiroz,Maria E. L. R. de, Oliveira,André F., Costa,Anna I. G., Assis,Roberta C., Andrade,Carlos E. O.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Journal of the Brazilian Chemical Society (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532014001100012
• topic: single drop microextration; pesticides; sensitive method; kinetics

The monitoring of pesticides in environmental samples at low concentrations is needed due to the risks that these compounds can pose to human health and the environment. In this work, a single drop microextraction (SDME) method was optimized and validated for the determination of trace concentrations of eight pesticides in water, using gas chromatography with electron capture detector (GC/ECD). The kinetics of the transfer of material from the aqueous phase to the organic phase during the extraction process was also evaluated. The method showed recoveries between 89.5 and 122.7%, with coefficients of variation smaller than 22.9%, and detection limits between 5.9 and 58.9 ng L-1. The method was applied to spiked samples at different concentration levels, and recoveries between 50.5 and 148% were obtained. The extraction process could be described by the Noyes-Whitney diffusion model, and methyl parathion showed the highest rate of transfer between the two phases.