报告题目: Ex-STORM: expansion single molecule nanoscopy
报告人: Zhisong Tong, Ph.D., Salk Institute for Biological Studies, USA
Zhisong Tong receives his M. Eng degree from Tianjin University, China, in 2008 and Ph.D. degree in physics from University of Miami, USA, in 2013. During his M. Eng period, he worked mainly on the design of metamaterials. His Ph.D. work involved studies on light scattering, light propagation, light imaging and light model design.Since 2013, he has been a Research Associate at Waitt Advanced Biophotonics Center at the Salk Institute for Biological Studies, where he studies and develops Ex-STORM super resolution technique. He has authored/co-authored more than 20 scientific publications and one book.
Fluorescence microscopy is one of the most widely used optical imaging methods in biomedical research. However, the spatial resolution of light microscopy, classically limited by the diffraction limit of light to several hundred nanometers, prevents its capability to resolve subcellular structures. In 2006, Stochastic Optical Reconstruction Microscopy (STORM), a single-molecule-based super resolution technique was developed by Xiaowei Zhuang (Harvard University) and improves the lateral resolution to about 20 nanometers. However, further enhancement of spatial resolution of single-molecule imaging is limited by the probe size (such as antibodies) and labeling density.In 2015, Expansion Microscopy (ExM), a super-resolution microscopy technique where specimen’s features of interest are imprinted onto a polymer hydrogel network and expanded resulting in physical magnification of the features, was developed by Ed Boyden (MIT). Thus, this process can be used to perform scalable super-resolution microscopy with diffraction-limited microscopes. However, ExM procedure causes severe bleaching (50 to 100%) of the majority of most common fluorophores, thus it is not suited for single-molecule imaging such as STORM. We developed an improved labeling strategy (Ex-STORM) that is free of bleaching, and therefore compatible with single-molecule nanoscopy. This novel imaging strategy has the potential to reach unprecedented resolution with optical microscopes.