H H Wills Physics Laboratory, University of Bristol, Bristol, United Kingdom.
Nano Lett. 2011 Feb 9;11(2):541-7. doi: 10.1021/nl1034489. Epub 2011 Jan 4.
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 ∼7 using interferometric cross-polarization microscopy at ultralow excitation powers (∼1 μW) 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.
金属纳米粒子在传感和成像中起着关键作用。在这里，我们展示了使用干涉交叉偏振显微镜在超低激发功率（约 1 μW）下检测尺寸低至 5nm 的金属颗粒的方法，其信噪比约为 7，可与单分子检测兼容。该方法无背景且不会产生热，因为它远在等离子体共振之外运行。无限的观察时间和蛋白大小的金属纳米粒子的结合在生物物理应用中具有巨大的潜力。
