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Abstract: Water-soluble CuInS2 ternary quantum dots (QDs) capped by mercaptopropionic acid were directly synthesized in aqueous solution. Consequently, the CuInS2 QDs were covalently linked to 3-aminophenyl boronic acid molecules to form the 3-aminophenyl boronic acid-functionalized CuInS2 QDs (F-CuInS2 QDs). The F-CuInS2 QDs had a fairly symmetric fluorescence emission centered at 736nm that was in the near-infrared region (NIR). The F-CuInS2 QDs containing boronic acid functional groups were reactive toward vicinal diols to form five- or six-member cyclic esters in an alkaline aqueous solution. The reaction would cause the fluorescence quenching, which could be used as a fluorescence probe for the determination of dopamine (DA). This assay could also probe other vicinal diols such as catechol, pyrogallol, and gallate, based on the fluorescence quenching of the F-CuInS2 QDs, and this assay was nearly unaffected by other phenol compounds such as phenol, resorcinol, and hydroquinone without the vicinal diol structures. The developed F-CuInS2 QDs were applied to the detection of DA in human serum samples with satisfactory results. Therefore, this experment provided a simple and sensitve NIR fluorescence probe for the detection of DA, catechol, pyrogallol, and gallate. [Copyright &y& Elsevier]

Determination of iodide ions has attracted considerable interest due to the importance and urgency. In the current work, we have developed a novel fluorescent and colorimetric platform for simple and selective detection of iodide ions based on the DNA-templated gold/silver nanoclusters (DNA-Au/Ag NCs). The detection system is based on the unique interaction between iodide ions and DNA-Au/Ag NCs, which shows an obvious fluorescence quenching with the addition of iodide ions and a good linear range from 0 to 10 μmol/L for iodide ions. In the mean time, the detection system also exhibits an obvious color change from colorless transparent to purple red with the addition of iodide ions. Furthermore, the proposed system has been successfully applied for determination of iodide ions in real water samples. [ABSTRACT FROM AUTHOR]