Center for Supramolecular Optoelectronic Materials, Research Institute of Advanced Materials (RIAM), Department of Materials Science and Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Korea.
Center for Theragnosis, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul, 02792, Korea.
Nat Commun. 2019 Jul 12;10(1):3089. doi: 10.1038/s41467-019-10986-4.
Dual-emissive systems showing color-specific photoswitching are promising in bioimaging and super-resolution microscopy. However, their switching efficiency has been limited because a delicate manipulation of all the energy transfer crosstalks in the systems is unfeasible. Here, we report a perfect color-specific photoswitching, which is rationally designed by combining the complete off-to-on fluorescence switching capability of a fluorescent photochromic diarylethene and the frustrated energy transfer to the other fluorescent dye based on the excited-state intramolecular proton transfer (ESIPT) process. Upon alternation of UV and visible light irradiations, the system achieves 100% switching on/off of blue emission from the diarylethene while orange emission from the ESIPT dye is unchanged in the polymer film. By fabricating this system into biocompatible polymer nanoparticles, we demonstrate microscopic imaging of RAW264.7 macrophage cells with reversible blue-color specific fluorescence switching that enables super-resolution imaging with a resolution of 70 nm.
双发射系统显示特定颜色的光致开关在生物成像和超分辨率显微镜中很有前景。然而，由于系统中所有能量转移串扰的精细操作是不可行的，因此它们的开关效率受到限制。在这里，我们报告了一种完美的特定颜色的光致开关，它通过将荧光光致变色二芳基乙烯的完全关闭到开启荧光转换能力与基于激发态分子内质子转移（ESIPT）过程的另一种荧光染料的受阻能量转移相结合来合理设计。在交替进行紫外光和可见光照射时，该系统在聚合物薄膜中实现了二芳基乙烯的蓝色发射的 100%开/关切换，而 ESIPT 染料的橙色发射保持不变。通过将该系统制成生物相容性聚合物纳米粒子，我们证明了 RAW264.7 巨噬细胞的微观成像具有可逆的蓝色特定荧光切换功能，可实现分辨率为 70nm 的超分辨率成像。
