Nanogap-engineerable Raman-active nanodumbbells for single-molecule detection
Nanogap-engineerable Raman-active nanodumbbells for single-molecule detection
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DOI：
10.1038/nmat2596
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发表时间：
2010-01-01
期刊：
影响因子：
41.2
通讯作者：
Suh, Yung Doug
中科院分区：
文献类型：
--
作者：
Lim, Dong-Kwon;Jeon, Ki-Seok;Suh, Yung Doug
基于表面增强拉曼散射（Sers）的等离子体纳米结构的信号放大和检测方法已被广泛研究用于成像和传感应用。然而，基于SERS的分子检测策略在实际中并不有用，因为没有直接的方法来合成和表征具有足够高的产率和效率的高度灵敏的SERS活性纳米结构，这导致在拉曼感测中的极低的横截面积。在这里，我们报告了一种高产量的SERS活性的金-银核-壳纳米哑铃的合成方法，其中两个纳米颗粒之间的差距和拉曼染料的位置和环境可以在纳米尺度上进行工程设计。原子力显微镜相关的纳米拉曼测量的个别哑铃结构表明，拉曼信号可以重复检测到单DNA拴系的纳米哑铃。这些程序化的纳米结构制造和单DNA检测策略为高产量合成光学活性智能纳米颗粒和结构可再现的基于纳米结构的单分子检测和生物测定开辟了道路。
Surface-enhanced Raman scattering (SERS)-based signal amplification and detection methods using plasmonic nanostructures have been widely investigated for imaging and sensing applications. However, SERS-based molecule detection strategies have not been practically useful because there is no straightforward method to synthesize and characterize highly sensitive SERS-active nanostructures with sufficiently high yield and efficiency, which results in an extremely low cross-section area in Raman sensing. Here, we report a high-yield synthetic method for SERS-active gold-silver core-shell nanodumbbells, where the gap between two nanoparticles and the Raman-dye position and environment can be engineered on the nanoscale. Atomic-force-microscope-correlated nano-Raman measurements of individual dumbbell structures demonstrate that Raman signals can be repeatedly detected from single-DNA-tethered nanodumbbells. These programmed nanostructure fabrication and single-DNA detection strategies open avenues for the high-yield synthesis of optically active smart nanoparticles and structurally reproducible nanostructure-based single-molecule detection and bioassays.