Background-Free Detection of Single 5 nm Nanoparticles through Interferometric Cross-Polarization Microscopy
Background-Free Detection of Single 5 nm Nanoparticles through Interferometric Cross-Polarization Microscopy
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DOI：
10.1021/nl1034489
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发表时间：
2011-02-01
期刊：
影响因子：
10.8
通讯作者：
Gersen, Henkjan
中科院分区：
文献类型：
--
作者：
Hong, Xin;van Dijk, Erik M. P. H.;Gersen, Henkjan
金属纳米颗粒在传感和成像中起着关键作用。在这里，我们展示了在与单分子检测兼容的超低激发功率（类似于1 μ W）下，使用干涉交叉偏振显微镜以类似于7的信噪比检测小至5 nm的金属颗粒。该方法是无背景的，并且不会产生加热，因为它远离等离子共振。无限的观察时间和蛋白质大小的金属纳米颗粒的结合在生物物理应用方面具有巨大的潜力。
Metal nanoparticles play a key role in sensing and imaging. Here we demonstrate the detection of metal particles down to 5 nm in size with a signal-to-noise ratio of similar to 7 using interferometric cross-polarization microscopy at ultralow excitation powers (similar to 1 mu W) compatible with single molecule detection. The method is background-free and induces no heating as it operates far from plasmonic resonance. The combination of unlimited observation time and protein-sized metal nanoparticles has great potential for biophysical applications.