State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China. College of Chemistry and Chemical Engineering, College of Biology, State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082, People's Republic of China.
Methods Appl Fluoresc. 2017 Mar 22;5(1):014011. doi: 10.1088/2050-6120/aa625d.
We present a facile one-pot, two-step strategy to prepare water-soluble dual-luminescent gold nanodots (AuNDs) and few-atom gold nanocluster composites simultaneously by using high molecular weight and hyperbranched polyethyleneimine (hPEI) as the protection ligand and stabilization agent. It was found that in the presence of hPEI, Au(III) ion can be reduced to a metastable Au(I) charge state in aqueous solution. Subsequently, adding 11-mercaptoundonioic acid induces parallel pathways of restricted Au(I) assembly, leading to the formation of both red-emitting hPEI stabilized AuNDs and blue-emitting hPEI-protected Au nanoclusters. The intensity ratio between the blue and red species shows a sensitive and reversible response to the solution pH in the range 2-11 and the dual-luminescent gold composites can act as an effective and reversible pH indicator.
我们提出了一种简便的一锅两步法，通过使用高分子量和超支化聚乙烯亚胺（hPEI）作为保护配体和稳定剂，同时制备水溶性双荧光金纳米点（AuNDs）和少原子金纳米簇复合材料。研究发现，在 hPEI 的存在下，Au（III）离子可以在水溶液中被还原为亚稳态的 Au（I）电荷态。随后，添加 11-巯基十一烷酸诱导受限的 Au（I）组装的平行途径，导致形成红色发射的 hPEI 稳定的 AuNDs 和蓝色发射的 hPEI 保护的 Au 纳米簇。蓝色和红色物种之间的强度比对 2-11 范围内的溶液 pH 表现出敏感和可逆的响应，双荧光金复合材料可以作为一种有效且可逆的 pH 指示剂。
