Metamaterial-Assisted Photobleaching Microscopy with Nanometer Scale Axial Resolution

• DOI: 10.1021/acs.nanolett.0c02056
• Publication Date: 2020-06-29T15:19:10Z
• Authors: Yeon Ui Lee; Junxiang Zhao; Gary C. H. Mo; Shilong Li; Guangru Li; Qian Ma; Qingqing Yang; Ratnesh Lal; Jin Zhang; Zhaowei Liu
• Keywords: 0301 basic medicine; 03 medical and health sciences

The past two decades have witnessed a dramatic progress in the development of novel super-resolution fluorescence microscopy technologies. Here, we report a new fluorescence imaging method, called metamaterial-assisted photobleaching microscopy (MAPM), which possesses a nanometer-scale axial resolution and is suitable for broadband operation across the entire visible spectrum. The photobleaching kinetics of fluorophores can be greatly modified via a separation-dependent energy transfer process to a nearby metamaterial. The corresponding photobleaching rate is thus linked to the distance between the fluorophores and the metamaterial layer, leading to a reconstructed image with exceptionally high axial resolution. We apply the MAPM technology to image the HeLa cell membranes tagged with fluorescent proteins and demonstrate an axial resolution of ∼2.4 nm with multiple colors. MAPM utilizes a metamaterial-coated substrate to achieve super-resolution without altering anything else in a conventional microscope, representing a simple solution for fluorescence imaging at nanometer axial resolution.