超分辨荧光成像是本世纪显微光学成像领域最重要的突破之一，被授予了2014年诺贝尔化学奖。其中，超分辨定位成像是一种代表性的超分辨荧光成像技术。该技术将单分子荧光成像与高精度分子定位算法相结合，在较简单的光学成像系统上，实现了20~30 nm的超高空间分辨率，为生物医学研究提供了前所未有的机会。近年来，人们普遍认为，高密度分子定位方法可以用于提高超分辨定位成像的时间分辨率。但是，目前所报道的高密度分子定位方法，计算速度普遍很慢，只适用于小视场原始图像的离线处理，大大限制了该技术的应用领域。
在武汉光电国家研究中心Britton Chance生物医学光子学研究中心黄振立教授的指导下，2015级博士生李路长等人基于分而治之策略开发了新型快速高密度分子定位方法。该方法获得了与同类方法相近的空间分辨率，并在速度上获得三到四个数量级的提升，实现了100 μm × 100 μm视场和10 ms曝光时间的高密度成像数据实时处理。该研究成果发表在2019年7月22日Optics Express, Vol. 27, Iss. 15, pp. 21029-21049。
图1. 三种高密度分子定位方法的数据处理结果比较
Figure 1. Evaluation of the localization performance among QC-STORM, ThunderSTORM and WindSTORM using experimental 2D images.
New advance in super-resolution fluorescence microscopy- Real-time maximum likelihood fitting of multiple emitters using the divide and conquer strategy
by Britton Chance Center for Biomedical Photonics
Super-resolution fluorescence microscopy is one of the most important breakthroughs in optical microscopy in the 21st century, and is awarded with the Nobel Prize for Chemistry in 2014. Super-resolution localization microscopy (SRLM) is a representative super-resolution imaging technique. With the combination of single-molecule fluorescence microscopy and high-precision molecule localization, SRLM is able to use a simple optical set-up to provide 20~30 nm spatial resolution that enables unprecedented opportunities for biomedical researches. In recent years, researchers have widely agreed that multi-emitter localization has great potential for maximizing the imaging speed of super-resolution localization microscopy. However, the slow image analysis speed of reported multi-emitter localization algorithms limits their usage in mostly off-line image processing with small image size.
Under the guidance of Prof. Zhen-Li Huang from Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Luchang Li (a PhD candidate in Huang’s group) and other group members adopted the well-known divide and conquer strategy in computer science and presented a fitting-based method called QC-STORM for fast multi-emitter localization. QC-STORM achieves 3-4 orders of magnitude in the image processing speed than the popular fitting-based ThunderSTORM and the up-to-date non-iterative WindSTORM, with similar localization precision and detection rate. Therefore, QC-STORM is capable of providing real-time full image processing on raw images with 100 µm × 100 µm field of view and 10 ms exposure time. This study is reported recently in Optics Express, 22nd July, 2019, Vol. 27, Iss. 15, pp. 21029-21049.
