Department of Chemistry, Indian Institute of Technology, Kharagpur 721302, India.
Langmuir. 2013 Feb 12;29(6):2033-43. doi: 10.1021/la304835p. Epub 2013 Jan 29.
Evolution of fluorescence from a giant core-shell particle is new and synergistic, which requires both gold and silver ions in an appropriate ratio in glutathione (GSH) solution. The formation of highly fluorescent Ag(2)/Ag(3) clusters on the surface of Au(I) assembly results in giant Au(I)(core)-Ag(0)(shell) water-soluble microparticles (~500 nm). Here, Au(I) acts as the template for the generation of fluorescent Ag clusters. The presence of gold under the synthetic strategy is selective, and no other metal supports such synergistic evolution. The core-shell particle exhibits stable and static emission (emission maximum, 565 nm; quantum yield, 4.6%; and stroke shift, 179 nm) with an average lifetime of ~25 ns. The drift of electron density by the Au(I) core presumably enhances the fluorescence. The positively charged core offers unprecedented long-term stability to the microparticles in aqueous GSH solution.
荧光从一个巨大的核壳粒子的演变是新的和协同的，这需要在谷胱甘肽（GSH）溶液中以适当的比例同时存在金和银离子。在 Au（I）组装体表面上形成高度荧光 Ag（2）/Ag（3）簇，导致巨大的 Au（I）（核）-Ag（0）（壳）水溶性微粒子（~500nm）。在这里，Au（I）作为生成荧光 Ag 簇的模板。金在合成策略下的存在是选择性的，没有其他金属支持这种协同演变。核壳粒子表现出稳定和静态发射（发射最大值，565nm；量子产率，4.6%；和斯托克位移，179nm），平均寿命约为 25ns。Au（I）核的电子密度漂移可能增强了荧光。带正电荷的核为微粒子在 GSH 水溶液中提供了前所未有的长期稳定性。
