11-Mercaptoundecanoic acid functionalized gold nanoclusters as fluorescent probes for the sensitive detection of Cu2+ and Fe3+ ions

Metal ions are physiologically essential, but excessive metal ions may cause severe risk to plants and animals. Here, we prepared gold nanoclusters (Au NCs) protected by 11-mercaptoundecanoic acid (11-MUA), which have excellent fluorescence properties for the detection of metal ions. The results showed that the copper ions (Cu2+) and iron ions (Fe3+) in the solution have obvious quenching effect on the fluorescence intensity of Au NCs. The detection range of Fe3+ was 0.8-4.5 mu mol/l, (R-2 = 0.992) and 4.5-11.0 (R-2 = 0.997). And Cu2+ has a lower linear range (0.1-1.0 mu mol/L, R-2 = 0.993). When EDTA was added into the reaction system, it was observed that the quenching effect of Cu2+ and Fe3+. on Au NCs showed different phenomenon. Then, the effect of metal ions on the fluorescence of Au NCs was investigated. The selective detection of Cu2+ was achieved by EDTA masking of Fe3+. In addition, we realized the metal ions detection application of Au NCs in the serum (C) 2017 Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. Published by Elsevier B.V. All rights reserved.