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

Abstract

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 0.020-4.00 ?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.