Gao He, Wu Pei, Song Pei, Kang Bin, Xu Jing-Juan, Chen Hong-Yuan
State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University Nanjing 210023 China
Chem Sci. 2021 Jan 4;12(8):3017-3024. doi: 10.1039/d0sc04764c.
Plasmonic nanoparticles (, gold, silver) have attracted much attention for biological sensing and imaging as promising nanoprobes. Practical biomedical applications demand small gold nanoparticles (Au NPs) with a comparable size to quantum dots and fluorescent proteins. Very small nanoparticles with a size below the Rayleigh limit (usually <30-40 nm) are hard to see by light scattering using a dark-field microscope, especially within a cellular medium. A photothermal microscope is able to detect very small nanoparticles, down to a few nanometers, but the imaging speed is usually too slow (minutes to hours) to image living cell processes. Here an absorption modulated scattering microscopy (AMSM) method is presented, which allows for the imaging of sub-10 nm Au NPs within a cellular medium. The unique physical mechanism of AMSM offers the remarkable ability to remove the light scattering background of the cellular component. In addition to having a sensitivity comparable to that of photothermal microscopy, AMSM has a much higher imaging speed, close to the video rate (20 fps), which allows for the dynamic tracking of small nanoparticles in living cells. This AMSM method might be a valuable tool for living cell imaging, using sub-10 nm Au NPs as biological probes, and thereby unlocking many new applications, such as single molecule labeling and the dynamic tracking of molecular interactions.
等离子体纳米颗粒（如金、银）作为有前景的纳米探针，在生物传感和成像方面备受关注。实际的生物医学应用需要尺寸与量子点和荧光蛋白相当的小金纳米颗粒（Au NPs）。尺寸低于瑞利极限（通常<30 - 40 nm）的非常小的纳米颗粒，使用暗场显微镜通过光散射很难看到，尤其是在细胞培养基中。光热显微镜能够检测到小至几纳米的非常小的纳米颗粒，但成像速度通常太慢（几分钟到几小时），无法对活细胞过程进行成像。在此提出一种吸收调制散射显微镜（AMSM）方法，它能够对细胞培养基中的亚10 nm Au NPs进行成像。AMSM独特的物理机制具有去除细胞成分光散射背景的显著能力。除了具有与光热显微镜相当的灵敏度外，AMSM具有更高的成像速度，接近视频速率（20 fps），这使得能够对活细胞中的小纳米颗粒进行动态跟踪。这种AMSM方法可能是一种用于活细胞成像的有价值工具，使用亚10 nm Au NPs作为生物探针，从而开启许多新的应用，如单分子标记和分子相互作用的动态跟踪。
Zotero 插件
