Lan Jing, Zhang Pu, Wang Ting Ting, Chang Yong, Lie Shao Qing, Wu Zhu Lian, Liu Zhong De, Li Yuan Fang, Huang Cheng Zhi
Key Laboratory of Luminescent and Real-Time Analytical Chemistry (Southwest University), Ministry of Education, College of Pharmaceutical Science, Southwest University, Chongqing 400715, China.
Analyst. 2014 Jul 7;139(13):3441-5. doi: 10.1039/c4an00505h.
Water-soluble fluorescent silver nanoclusters (AgNCs) with almost seven and nine silver atoms and a quantum yield (QY) of 5.38 ± 0.25% were successfully prepared via one-pot hydrothermal synthesis using polymethacrylic acid sodium salt (PMAA-Na) as a template. The as-prepared PMAA-AgNCs displayed a mono-distribution, they were uniform in size and the color of the fluorescence, emitting at 579 nm, was orange when excited at 502 nm. What is more, we found that the as-prepared PMAA-AgNCs could be quenched by sulfides based on the formation of a metal-ligand bond Ag-S, and thus sulfides could be sensitively detected by spectrofluorometry. As proof of concept, thiourea (TU) and other sulfides including cysteine (Cys), glutathione (GSH) and dl-methionine could be detected. For example, the color of the orange fluorescent AgNCs solutions darkened upon the addition of TU and the fluorescence of PMAA-AgNCs was quenched. The detection limit for TU was 6.10 μM in the linear range from 8.57 μM to 2.29 mM.
通过以聚甲基丙烯酸钠盐（PMAA-Na）为模板的一锅水热合成法，成功制备了具有近七个和九个银原子且量子产率（QY）为5.38±0.25%的水溶性荧光银纳米团簇（AgNCs）。所制备的PMAA-AgNCs呈现单分散分布，尺寸均匀，荧光颜色为橙色，在502nm激发时发射波长为579nm。此外，我们发现所制备的PMAA-AgNCs可基于金属-配体键Ag-S的形成被硫化物淬灭，因此可通过荧光光谱法灵敏地检测硫化物。作为概念验证，可检测硫脲（TU）以及包括半胱氨酸（Cys）、谷胱甘肽（GSH）和dl-蛋氨酸在内的其他硫化物。例如，加入TU后橙色荧光AgNCs溶液的颜色变深，且PMAA-AgNCs的荧光被淬灭。TU在8.57μM至2.29mM的线性范围内的检测限为6.10μM。
