Jiang Liwen, Sun Xuqing, Liu Hongyao, Wei Ruxue, Wang Xue, Wang Chang, Lu Xinchao, Huang Chengjun
Institute of Microelectronics of Chinese Academy of Sciences, Beijing 100029, China.
Currently with Center for Terahertz Waves, College of Precision Instrument and Optoelectronics Engineering, and the Key laboratory of Opto-electronics Information and Technology (Ministry of Education), Tianjin University, Tianjin 300072, China.
Nanomaterials (Basel). 2020 Mar 27;10(4):615. doi: 10.3390/nano10040615.
Label-free, fast, and single nanoparticle detection is demanded for the in situ monitoring of nano-pollutants in the environment, which have potential toxic effects on human health. We present the label-free imaging of single nanoparticles by using total internal reflection (TIR)-based leakage radiation microscopy. We illustrate the imaging of both single polystyrene (PS) and Au nanospheres with diameters as low as 100 and 30 nm, respectively. As both far-field imaging and simulated near-field electric field intensity distribution at the interface showed the same characteristics, i.e., the localized enhancement and interference of TIR evanescent waves, we confirmed the leakage radiation, transforming the near-field distribution to far-field for fast imaging. The localized enhancement of single PS and Au nanospheres were compared. We also illustrate the TIR-based leakage radiation imaging of single polystyrene nanospheres with different incident polarizations. The TIR-based leakage radiation microscopy method is a competitive alternative for the fast, in situ, label-free imaging of nano-pollutants.
环境中的纳米污染物对人类健康具有潜在毒性影响，因此需要对其进行原位监测，这就要求实现无标记、快速且能对单个纳米颗粒进行检测。我们利用基于全内反射（TIR）的泄漏辐射显微镜对单个纳米颗粒进行无标记成像。我们展示了分别对直径低至100 nm和30 nm的单个聚苯乙烯（PS）纳米球和金纳米球的成像。由于远场成像和界面处模拟的近场电场强度分布都显示出相同的特征，即TIR倏逝波的局部增强和干涉，我们证实了泄漏辐射，即将近场分布转换为远场以实现快速成像。比较了单个PS和金纳米球的局部增强情况。我们还展示了不同入射偏振下单个聚苯乙烯纳米球基于TIR的泄漏辐射成像。基于TIR的泄漏辐射显微镜方法是对纳米污染物进行快速、原位、无标记成像的一种有竞争力的替代方法。
