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Trypsin-Stabilized Fluorescent Gold Nanocluster for Sensitive and Selective Hg2+ Detection

Department of Chemistry and Materials Engineering, Faculty of Chemistry, Materials and Bioengineering, Kansai University, 3-3-35 Yamate, Suita, Osaka 564–8680, Japan.
Analytical Sciences (Impact Factor: 1.4). 01/2011; 27(6):591-6. DOI: 10.2116/analsci.27.591
Source: PubMed

ABSTRACT We report on trypsin-stabilized fluorescent gold nanoclusters (Au NCs) for the sensitive and selective detection of Hg(2+) ions. The Au NCs have an average size of 1 nm and show a red emission at 645 nm. The photostable properties of the trypsin-stabilized Au NCs were examined, and their photochemical stability was found to be similar to that of CdSe quantum dots. The fluorescence was particularly quenched by Hg(2+), and therefore the Au NCs can be used as fluorescent sensors for sensitive and selective Hg(2+) detection to a detection limit of 50 ± 10 nM and the quantitative detection of Hg(2+) in wide and low concentration range of 50-600 nM.

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