DNA-Based Nanotemplate Directed In Situ Synthesis of Silver Nanoclusters with Specific Fluorescent Emission: Surface-Guided Chemical Reactions

详细信息    查看全文

• 作者：Zhen-Gang Wang ; Qing Liu ; Na Li ; Baoquan Ding
• 刊名：Chemistry of Materials
• 出版年：2016
• 出版时间：December 13, 2016
• 年：2016
• 卷：28
• 期：23
• 页码：8834-8841
• 全文大小：469K
• ISSN：1520-5002

文摘

DNA-hosted silver nanoclusters (AgNCs) are a set of metallic fluorescent nanodots that possess high quantum yields and photostability. Here, we show the in situ hosted synthesis of AgNCs by single-stranded DNA preorganized on the self-assembled DNA nanostructure templates, which results in the site-specific formation of AgNCs with the specific fluorescence wavelengths. The excitation/emission properties of AgNCs were tuned by adjusting the distance between nucleation site and the template, the template configuration, and the location of the nucleation site on the template. Mass spectra analysis of AgNC products was performed to study the cluster sizes. The 5′ and 3′ ends of freely diffusing and template-supported host strands were labeled with a donor and an acceptor, and the FRET efficiency was evaluated to reveal the conformations of the host strands and their complexes with Ag⁺. It is indicated that the rigid template guided the synthetic pathway toward the preferential synthesis of AgNCs with a specific size distribution via a steric effect on the Ag⁺ adsorption to the host strands, which produces the specifically emissive AgNCs.