Manganese modified CdTe/CdS quantum dots as a highly selective probe to detect trace copper element in beer samples

This paper describes the investigation of manganese modified CdTe/CdS quantum dots as a fluorescence probe for trace copper detection. Manganese modified CdTe/CdS quantum dots were prepared in aqueous solution and were characterized by ultraviolet-visible absorbance, fluorescence spectra, transmission electron microscopy and X-ray diffraction. The as-synthesized manganese modified CdTe/CdS QDs presented a high photoluminescence quantum yield of 84%. The functionalized nanoparticles were used as a fluorescence probe for Cu2+. The interference study demonstrated that the normal foreign ions, such as Na+, Mg2+, Al3+ et al., had very low interference for the detection of Cu2+, and the calibration plot of F-0/F versus concentration of Cu2+ was linear in the range of 5.0 x 10(-9) to 5.0 x 10(-7) mol L-1 with a correlation coefficient of 0.9991. The ultrasensitive fluorescence probe built was directly applied to the detection of trace copper element in beer samples with satisfactory results.