Zhang Yuanyuan, Jiang Hui, Wang Xuemei
State Key Lab of Bioelectronics (Chien-Shiung Wu Laboratory), Southeast University, No. 2 Sipailou, Nanjing 210096, PR China.
State Key Lab of Bioelectronics (Chien-Shiung Wu Laboratory), Southeast University, No. 2 Sipailou, Nanjing 210096, PR China.
Anal Chim Acta. 2015 Apr 22;870:1-7. doi: 10.1016/j.aca.2015.01.016. Epub 2015 Jan 14.
In this study, we have developed a label-free, dual functional detection strategy for highly selective and sensitive determination of aqueous Ag(+) and Hg(2+) by using cytidine stabilized Au NCs and AuAg NCs as fluorescent turn-on and turn off probes, respectively. The Au NCs and AuAg NCs showed a remarkably rapid response and high selectivity for Ag(+) and Hg(2+) over other metal ions, and relevant detection limit of Ag(+) and Hg(2+) is ca. 10 nM and 30 nM, respectively. Importantly, the fluorescence enhanced Au NCs by doping Ag(+) can be conveniently reusable for the detection of Hg(2+) based on the corresponding fluorescence quenching. The sensing mechanism was based on the high-affinity metallophilic Hg(2+)-Ag(+) interaction, which effectively quenched the fluorescence of AuAg NCs. Furthermore, these fluorescent nanoprobes could be readily applied to Ag(+) and Hg(2+) detection in environmental water samples, indicating their possibility to be utilized as a convenient, dual functional, rapid response, and label-free fluorescence sensor for related environmental and health monitoring.
在本研究中，我们开发了一种无标记的双功能检测策略，通过分别使用胞苷稳定的金纳米簇（Au NCs）和金银纳米簇（AuAg NCs）作为荧光开启和关闭探针，用于高选择性和灵敏地测定水溶液中的Ag(+)和Hg(2+)。Au NCs和AuAg NCs对Ag(+)和Hg(2+)表现出显著快速的响应以及相对于其他金属离子的高选择性，Ag(+)和Hg(2+)的相关检测限分别约为10 nM和30 nM。重要的是，通过掺杂Ag(+)使荧光增强的Au NCs基于相应的荧光猝灭可方便地重复用于Hg(2+)的检测。传感机制基于高亲和力的亲金属Hg(2+)-Ag(+)相互作用，其有效地猝灭了AuAg NCs的荧光。此外，这些荧光纳米探针可容易地应用于环境水样中Ag(+)和Hg(2+)的检测，表明它们有可能被用作一种方便、双功能、快速响应且无标记的荧光传感器用于相关的环境和健康监测。
