Peng Yan, Wang Pei, Luo Liang, Liu Lang, Wang Fu
College of Chemistry and Chemical Engineering, Xinjiang University, Urumqi 830046, Xinjiang, China.
Laboratory of Environmental Sciences and Technology, Xinjiang Technical Institute of Physics & Chemistry, Chinese Academy of Sciences, Urumqi 830011, Xinjiang, China.
Materials (Basel). 2018 Jan 26;11(2):191. doi: 10.3390/ma11020191.
Metal nanoclusters, with dimensions between atomic and nanoparticles, have attracted a great deal of attention due to their significantly unusual properties. Water-soluble palladium nanoclusters (Pd NCs) with blue-green fluorescence were synthesized by a water bath heating method, with methionine as a stabilizer and ascorbic acid as a reducing agent. We investigated the optimal synthesis conditions, stability, and pH response of the obtained products in detail. The synthesized materials were characterized by ultraviolet-absorption spectroscopy, fluorescence spectroscopy, high-resolution transmission electron microscopy, and atomic force microscopy. These experimental results showed that the Pd NCs had a small size of ~1.91 nm, with a uniform size distribution. Additionally, the Pd NCs emitted blue-green fluorescence under ultraviolet light with a quantum yield of 5.47%. Notably, both stabilizers and reducing agents used in this synthesis method are nutrients for humans, non-toxic, and harmless. This method could be viewed as a biologically friendly and green way of preparing fluorescent metal nanoclusters. The as-prepared fluorescent Pd NCs also possessed excellent fluorescence detection ability and were very sensitive to low concentrations of hemoglobin, with a linear response in the range of 0.25-3.5 μM and a detection limit of 50 nM.
尺寸介于原子和纳米颗粒之间的金属纳米团簇因其显著异常的性质而备受关注。以蛋氨酸为稳定剂、抗坏血酸为还原剂，通过水浴加热法合成了具有蓝绿色荧光的水溶性钯纳米团簇（Pd NCs）。我们详细研究了所得产物的最佳合成条件、稳定性和pH响应。通过紫外吸收光谱、荧光光谱、高分辨率透射电子显微镜和原子力显微镜对合成材料进行了表征。这些实验结果表明，Pd NCs尺寸小，约为1.91 nm，尺寸分布均匀。此外，Pd NCs在紫外光下发射蓝绿色荧光，量子产率为5.47%。值得注意的是，该合成方法中使用的稳定剂和还原剂都是人体所需营养物质，无毒无害。该方法可被视为一种生物友好型的绿色制备荧光金属纳米团簇的方法。所制备的荧光Pd NCs还具有出色的荧光检测能力，对低浓度血红蛋白非常敏感，线性响应范围为0.25 - 3.5 μM，检测限为50 nM。
