Determination of carbaryl and its metabolite 1-naphthol in water samples by fluorescence spectrophotometer after anionic surfactant micelle-mediated extraction with sodium dodecylsulfate.

Anionic surfactant micelle-mediated extraction with sodium dodecylsulfate (SDS) was applied as preconcentration step prior to fluorescence spectrophotometer without further cleanup step. The obtained surfactant-rich phase was diluted to a fixed volume with water-miscible solvents. Carbaryl and its metabolite 1-naphthol were used as test compounds. The detection limits (LODs) of the method were in the microgram per liter area. Recoveries obtained from four real water samples ranged from 90.7 to 98.6%. Under the optimum experimental conditions, the method described showed a good precision, with relative standard deviations (R.S.D.) of less than 6%. According to the results, this approach reduced the viscidity of the surfactant-rich phase and made the combination of fluorescence spectrophotometer with anionic surfactant micelle-mediated extraction much easier.