Kim Seokho, Kim Bo-Hyun, Hong Young Ki, Cui Chunzhi, Choi Jinho, Park Dong Hyuk, Song Sung Ho
Department of Chemical Engineering, Inha University, Incheon 22212, Korea.
Division of Advanced Materials Engineering, Kongju National University, Chungnam 31080, Korea.
Polymers (Basel). 2020 Mar 10;12(3):631. doi: 10.3390/polym12030631.
We experimentally demonstrate the simultaneous enhancement of Raman and photoluminescence (PL) of core-shell hybrid nanoparticles consisting of Ag (core) and polydiacetylene (PDA, shell) through the assistance of localized surface plasmon (LSP) effect for the effective biosensor. Core-shell nanoparticles (NPs) are fabricated in deionized water through a sequential process of reprecipitation and self-assembly. The Raman signal of PDA on core-shell NPs is enhanced more than 100 times. Also, highly enhanced photoluminescence is observed on Ag/PDA hybrid NPs after coupling of the complementary -DNA with -DNA which are immobilized on PDA shell. This indicates that the core Ag affects the Raman and PL of PDA through the LSP resonance, which can be caused by the energy and/or charge transfer caused by the LSP coupling and the strong electromagnetic field near Ag NP surface. Only electrons present on the surface interact with the PDA shell, not involving the electrically neutral part of the electrons inside the Ag NP. Furthermore, this work shows that as prepared Ag/PDA NPs functionalized by probe DNA can sense the target DNA with an attomolar concentration (100 attomole).
我们通过局域表面等离子体（LSP）效应的辅助，实验证明了由银（核）和聚二乙炔（PDA，壳）组成的核壳混合纳米粒子的拉曼和光致发光（PL）同时增强，以用于有效的生物传感器。核壳纳米粒子（NPs）通过再沉淀和自组装的顺序过程在去离子水中制备。核壳NPs上PDA的拉曼信号增强了100倍以上。此外，在固定于PDA壳上的互补DNA与DNA偶联后，在Ag/PDA混合NPs上观察到高度增强的光致发光。这表明核银通过LSP共振影响PDA的拉曼和PL，这可能是由LSP耦合以及Ag NP表面附近的强电磁场引起的能量和/或电荷转移所致。只有表面存在的电子与PDA壳相互作用，不涉及Ag NP内部电子的电中性部分。此外，这项工作表明，由探针DNA功能化的制备好的Ag/PDA NPs能够检测到浓度为阿托摩尔（100阿托摩尔）的目标DNA。
