Construction of Plasmonic Core鈥揝atellite Nanostructures on Substrates Based on DNA-Directed Self-Assembly as a Sensitive and Reproducible Biosensor

详细信息    查看全文

• 作者：Tingting Zhang ; He Li ; Shengwei Hou ; Youqing Dong ; Guangsheng Pang ; Yingwei Zhang
• 刊名：ACS Applied Materials & Interfaces
• 出版年：2015
• 出版时间：December 16, 2015
• 年：2015
• 卷：7
• 期：49
• 页码：27131-27139
• 全文大小：542K
• ISSN：1944-8252

文摘

We report the successful construction of plasmonic core鈥搒atellite nanostructured assemblies on two-dimensional substrates, based on a strategy of combining DNA-functionalized plasmonic nanoparticles (NPs) with the specific recognition ability toward target to enable satellite NPs to self-assemble around the core immobilized on substrates. A strongly coupled plasmonic resonance band was observed because of the close proximity between core and satellite NPs, which presented significant red-shift and enhanced extinction with respect to the local surface plasmon resonance (LSPR) band of individual core NPs on the substrate. The functionality of this core鈥搒atellite nanostructured assembly as a biosensor was further explored, and the changes in extinction intensity and the peak shift of the plasmonic coupling resonance band arising from the probe-target DNA binding event all proved to be useful criteria for target DNA detection. Moreover, high selectivity down to single-base mismatched DNA was achieved using this strongly coupled plasmonic core鈥搒atellite nanostructured assembly on a substrate. Such substrate-based detection was advantageous, and its reusability and high cycle stability were demonstrated after five cycles of disassembly and reassembly. Our work demonstrates the biosensing capacity of this DNA-functionalized plasmonic nanoassembly model system on two-dimensional substrate, which is also applicable to the detection of numerous DNA-recognized biomolecules. Likewise, the presented construction method can be extended to fabricate other compositional core鈥搒atellite nanoassemblies.