State Key Laboratory of Modern Optical Instrumentation, Centre for Optical and Electromagnetic Research, Zhejiang Provincial Key Laboratory for Sensing Technologies, Zhejiang University, Hangzhou, 310058, China.
Department of Chemistry, Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, Division of Life Science, State Key Laboratory of Molecular Neuroscience, Institute for Advanced Study, Institute of Molecular Functional Materials, Division of Biomedical Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China.
Adv Mater. 2017 Nov;29(43). doi: 10.1002/adma.201703643. Epub 2017 Oct 4.
Stimulated emission depletion (STED) nanoscopy is a typical super-resolution imaging technique that has become a powerful tool for visualizing intracellular structures on the nanometer scale. Aggregation-induced emission (AIE) luminogens are ideal fluorescent agents for bioimaging. Herein, long-term super-resolution fluorescence imaging of cancer cells, based on STED nanoscopy assisted by AIE nanoparticles (NPs) is realized. 2,3-Bis(4-(phenyl(4-(1,2,2-triphenylvinyl)phenyl)amino)phenyl) fumaronitrile (TTF), a typical AIE luminogen, is doped into colloidal mesoporous silica to form fluorescent NPs. TTF@SiO NPs bear three significant features, which are all essential for STED nanoscopy. First, their STED efficiency can reach more than 60%. Second, they are highly resistant to photobleaching, even under long-term and high-power STED light irradiation. Third, they have a large Stokes' shift of ≈150 nm, which is beneficial for restraining the fluorescence background induced by the STED light irradiation. STED nanoscopy imaging of TTF@SiO -NPs-stained HeLa cells is performed, exhibiting a high lateral spatial resolution of 30 nm. More importantly, long-term (more than half an hour) super-resolution cell imaging is achieved with low fluorescence loss. Considering that AIE luminogens are widely used for organelle targeting, cellular mapping, and tracing, AIE-NPs-based STED nanoscopy holds great potential for many basic biomedical studies that require super-resolution and long-term imaging.
受激发射耗散(STED)纳米显微镜是一种典型的超分辨率成像技术,已成为在纳米尺度上可视化细胞内结构的有力工具。聚集诱导发射(AIE)发光体是生物成像的理想荧光剂。在此,基于 STED 纳米显微镜辅助的 AIE 纳米粒子(NPs)实现了癌细胞的长时超分辨率荧光成像。2,3-双(4-(苯基(4-(1,2,2-三苯基乙烯基)苯基)氨基)苯基)丁二腈(TTF),一种典型的 AIE 发光体,掺杂到胶体介孔硅中形成荧光 NPs。TTF@SiO NPs 具有三个重要特征,这对于 STED 纳米显微镜都是必不可少的。首先,它们的 STED 效率可以达到 60%以上。其次,它们具有很强的抗光漂白性,即使在长时间和高功率 STED 光照射下也是如此。第三,它们具有约 150nm 的大斯托克斯位移,有利于抑制 STED 光照射引起的荧光背景。对 TTF@SiO-NPs 染色的 HeLa 细胞进行 STED 纳米显微镜成像,显示出 30nm 的高横向空间分辨率。更重要的是,实现了具有低荧光损耗的长时间(超过半小时)超分辨率细胞成像。鉴于 AIE 发光体广泛用于细胞器靶向、细胞映射和示踪,基于 AIE-NPs 的 STED 纳米显微镜在需要超分辨率和长时成像的许多基础生物医学研究中具有很大的潜力。