MICELLAR FLUORESCENCE ENHANCEMENT OF CARBAMATE PESTICIDES

Different studies have been carried out on the interaction of carbamate pesticides, such as carbofuran and carbaryl, with nonionic and anionic surfactants. Micellar fluorescence enhancements (MEF) of 15-20 for carbofuran in the presence of fatty alcohol ethylene oxide condensates, and of 3.7-8.6 in the presence of anionic surfactants at neutral pH have been obtained. Carbaryl does not interact with surfactants, but when it is hydrolysed to 1-naphthol, MEF values of the order of 2 are obtained in the presence of nonylphenol ethylene oxide condensates. The experimental parameters have been optimized in order to obtain maximum fluorescence. The mechanisms involved in the fluorescence enhancement supposes an increase in the fluorescence quantum yield and no increase in the extinction coefficient was observed at the excitation wavelength. © 1990.