Synthesis of cysteamine-coated CdTe quantum dots for the detection of bisphenol A

Cadmium telluride quantum dots (QDs) were prepared and coated with cysteamine using ultrasonic irradiation. The QDs were characterized by fluorescence spectroscopy, UV-vis absorption spectra, X-ray diffraction and infrared spectroscopy. The QDs possess a quantum yield as high as 46% and a quite narrow emission band (full width at half maximum of 38 nm). The fluorescence of these QDs is quenched by bisphenol A (BPA), and quenching can be described by a Stern-Volmer equation with correlation coefficient of 0.998. These findings resulted in a simple and rapid technique for determination of BPA that was applied to its determination in feeding bottles.