Photo-Switchable Cyanine Dyes for Super-Resolution Microscopy

超分辨率显微镜为研究活体的细胞过程提供了独特的机会。为了确保获得高分辨率的图像，需要可光激活的染料，这种染料可以通过用光照射从暗(关)状态转变为高发射(开)状态。到目前为止，可光切换蛋白经常被使用，但超分辨率显微镜的更广泛使用变得有限，因为它们的光稳定性低，从遗传物质中生产的成本很高。此外，这种策略不能用于标记内源性蛋白质。相比之下，合成分子开关的使用仍未得到充分探索。已经发明了几种有机染料的设计，但大多数都需要紫外线照射来诱导切换过程，这是活细胞成像的一个关键方面。因此，我的研究项目集中在开发新的光开关染料，这种染料具有高度的光稳定性，并且可以在可见光下切换。从之前在柏林自由大学进行的研究中，我可以在菁染料的合成和光学性质的化学调节方面获得更多的知识。进一步的研究证实了它们适合作为活细胞成像的染料标记。我将与英国牛津大学安德森教授的团队一起，进一步将菁染料开发成定制的分子光开关，使其具有优化的光物理性能，用于高分辨率显微镜。这个项目将建立在我现有的菁染料化学调谐专业知识的基础上，并将与安德森实验室(英国牛津)关于可光切换染料的专业知识相结合。综上所述，我将探索可光切换的菁染料用于活细胞的超分辨率显微镜的潜力，从而有助于更好地了解生命系统。

Super-resolution microscopy offers the unique opportunity to investigate cellular processes in living organisms. To ensure the acquisition of high resolution images, photoactivatable dyes are required which can be turned from dark (OFF) to highly emissive (ON) states by irradiation with light. To date, photoswitchable proteins are frequently used, but broader utilisation for super-resolution microscopy becomes limited by their low photostability and costly production from genetic material. Furthermore, this strategy cannot be used to label endogenous proteins. In contrast, the use of synthetic molecular switches remains under-explored. Several designs of organic dyes have been invented, but most of them require ultraviolet irradiation to induce the switching process, which is a critical aspect for live cell imaging. My research project therefore focuses on the development of new photoswitchable dyes which are highly photostable and switchable with visible light. From previous studies that were performed at the Freie Universität Berlin, I could gain extended knowledge on the synthesis of cyanine dyes and chemical tuning of their optical properties. Further investigations confirmed their suitability as dye labels for live cell imaging. Together with the group of Professor Anderson (Oxford, UK) I will further develop cyanine dyes into custom-built molecular photoswitches with optimised photophysical properties for high-resolution microscopy. This project will build on my existing expertise on chemical tuning of cyanine dyes and will be combined with the expertise on photoswitchable dyes of the Anderson Laboratory (Oxford, UK). Taken together, I will explore the potential of photoswitchable cyanine dyes for super-resolution microscopy of living cells, thus contributing towards a better understanding of living systems.