非共振分子的单分子表面增强拉曼光谱
Evan J Blackie1, Eric C Le Ru, Pablo G Etchegoin
1The MacDiarmid Institute for Advanced Materials and Nanotechnology, School of Chemical and Physical Sciences, Victoria University of Wellington, P.O. Box 600, Wellington, New Zealand.
Journal of the American Chemical Society
|October 8, 2009
概括
单分子表面增强拉曼散射 (SERS) 检测非共振分子现在可以使用双分析SERS方法. 这种技术量化了增强因子,揭示了单分子SERS分析的检测极限.
科学领域:
- 分析化学 分析化学
- 频谱学是一种光谱学.
- 纳米技术 纳米技术
背景情况:
- 单分子检测对于理解化学和生物过程至关重要.
- 表面增强拉曼散射 (SERS) 提供高灵敏度,但面临着与非共振分子的挑战.
- 双分析SERS方法使用合作分子来增强检测.
研究的目的:
- 通过使用双分析SERS方法来证明和量化非共振分子的单分子SERS检测.
- 确定单分子SERS所需的最小增强因子.
- 将这种方法扩展到挑战小非共振分子,如腺因.
主要方法:
- 在633nm激发下实验证明白酸SERS.
- 使用1,2-di-(4-pyridyl) -乙烯 (BPE) 和二衍生物作为分析剂.
- 应用同位素替代的腺素作为白分析SERS合作伙伴用于腺素检测.
- 量化单分子事件的SERS截面.
主要成果:
- 成功检测非共振BPE的单分子SERS检测得到了大约5 x 10^9.9的增强因子.
- 对于BPE,最大观察到的增强因子达到大约5 x 10^10 .
- 检测单个分子的腺因需要更高的增强因子,大约10^11.
- 量化了单分子事件的SERS截面.
结论:
- 双分析SERS方法能够在单个分子水平上对非共振分子进行敏感检测.
- 这项研究提供了对单分子SERS的最低检测极限的定量见解.
- 这些发现建立了对SERS应用程序增强因子要求的基本理解.
相关概念视频
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The underlying principle of Raman spectroscopy is based on the interaction between light and matter, specifically molecules' inelastic scattering of photons. When a monochromatic beam of light, typically from a laser source, interacts with a sample, most scattered light has the same frequency as the incident light. This is known as Rayleigh scattering.
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