Water-Soluble InP/ZnS QDs as Dibutyl Phthalate Markers. The Influence of Alcohol on the Solubility of Phthalates

摘要

The interaction of water-soluble semiconductor InP/ZnS-PEG-COOH quantum dots (QDs) with dibutyl phthalate (DBP) in samples of fresh and sea water is studied. It is found that an increase in the DBP concentration in fresh water with InP/ZnS QDs leads to an increase in the QD luminescence amplitude. This increase is caused by localization of DBP molecules in the Onsager cavity of the QD and passivation of its surface. An increase in the ethanol concentration improves the DBP solubility and can be used for increasing the sensitivity of detection of phthalates in aqueous media. The investigations of samples with waters of the Black, Mediterranean, and White seas showed an individual character of interaction of InP/ZnS QDs with DBP and different luminescence dynamics with increasing ethanol concentrations. It is found that plastic packaging of products containing alcohol is potentially hazardous to human health.