Photo-Switchable Cyanine Dyes for Super-Resolution Microscopy

超分辨率显微镜提供了独特的机会来研究活生物体中的细胞过程。为了确保获得高分辨率图像，需要可光活化的染料，其可以通过用光照射从暗（OFF）转变为高发射（ON）状态。到目前为止，光开关蛋白经常使用，但超分辨率显微镜的更广泛利用受到其低光稳定性和从遗传物质生产成本的限制。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然未得到充分探索。已经发明了几种有机染料的设计，但它们中的大多数需要紫外线照射来诱导转换过程，这是活细胞成像的关键方面。因此，我的研究项目集中在开发新的光开关染料，这些染料具有高度的光稳定性和可见光开关。从以前在自由大学柏林进行的研究中，我可以获得有关花青染料合成及其光学性质的化学调谐的扩展知识。进一步的研究证实了它们作为活细胞成像的染料标记的适用性。我将与安德森教授（英国牛津）的团队一起，进一步开发花青染料，使其成为定制的分子光开关，具有优化的物理特性，可用于高分辨率显微镜。这个项目将建立在我现有的花青染料的化学调谐的专业知识，并将结合光开关染料的安德森实验室（牛津，英国）的专业知识。综上所述，我将探索光开关花青染料的潜力，用于活细胞的超分辨率显微镜，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.