Gold Nanoclusters Templated by Poly-cytosine DNA as Fluorescent Probes for Selective and Sensitive Detection of Thiocyanate

Abstract Gold nanoclusters(AuNCs) were prepared in the presence of the nucleobases of poly-cytosine DNAs in this paper. We have demonstrated that the fluorescence of the AuNCs is quenched by thiocyanate($ SCN^{−} $) through the interaction between $ SCN^{−} $ and gold atoms. AuNCs can receive energy...
Ausführliche Beschreibung

Abstract Gold nanoclusters(AuNCs) were prepared in the presence of the nucleobases of poly-cytosine DNAs in this paper. We have demonstrated that the fluorescence of the AuNCs is quenched by thiocyanate($ SCN^{−} $) through the interaction between $ SCN^{−} $ and gold atoms. AuNCs can receive energy from nucleobases to boost their emission intensity, while in the presence of $ SCN^{−} $, they coordinate with Au atoms and influence the energy transfer between the nucleobases and AuNCs, leading to the fluorescence quenching. The decreased fluorescence intensity was in proportion to the concentration of $ SCN^{−} $ in the range of 8.0×$ 10^{−7} $–1.5×$ 10^{−5} $ mol/L with a limit of detection of 4.2×$ 10^{−7} $ mol/L(3σ). We further validated the practice of this probe through the detection of $ SCN^{−} $ in natural water samples. Ausführliche Beschreibung