A Synergistic Sensitized Fluorescent Determination of 2,4-Dichlorophenoxyacetic Acid in Vegetable Samples Based on the Derivatives of Calix[4]arene

A novel fluorescent determination of 2,4-dichlorophenoxyacetic acid (2,4-D) based on the derivatives of calix[4]arene (SAX) in ?-cyclodextrin(?-CD)/ sodium dodecyl sulfate ( SDS ) synergistic sensitized system was developed. The results were shown that the fluorescence intensity of SAX could be quenched by 2,4-D, and the fluorescence quenching ( ? F=F SAX -F 2,4-D -SAX ) was synergistic sensitized in ?-CD/ SDS medium . Under the conditions of ? ex/em =332/468 nm and pH 7.0, the linear range for 2,4-D were found to be 0.020 - 4.0 0 ?g/mL . The mechanism of determination was discussed with quenching type analysis, inclusion interaction and sensitizing effect. This method has been applied for the determination of 2,4-D in vegetable samples with satisfactory results.