State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China.
Optical Microscopy Facility, Max Planck Institute for Medical Research, Heidelberg, 69120, Germany.
Nat Commun. 2022 Apr 27;13(1):2264. doi: 10.1038/s41467-022-29547-3.
The quality and application of super-resolution fluorescence imaging greatly lie in the dyes' properties, including photostability, brightness, and Stokes shift. Here we report a synergistic strategy to simultaneously improve such properties of regular fluorophores. Introduction of quinoxaline motif with fine-tuned electron density to conventional rhodamines generates new dyes with vibration structure and inhibited twisted-intramolecular-charge-transfer (TICT) formation synchronously, thus increasing the brightness and photostability while enlarging Stokes shift. The new fluorophore YL578 exhibits around twofold greater brightness and Stokes shift than its parental fluorophore, Rhodamine B. Importantly, in Stimulated Emission Depletion (STED) microscopy, YL578 derived probe possesses a superior photostability and thus renders threefold more frames than carbopyronine based probes (CPY-Halo and 580CP-Halo), known as photostable fluorophores for STED imaging. Furthermore, the strategy is well generalized to offer a new class of bright and photostable fluorescent probes with long Stokes shift (up to 136 nm) for bioimaging and biosensing.
超分辨率荧光成像的质量和应用主要取决于染料的特性，包括光稳定性、亮度和斯托克斯位移。在这里，我们报告了一种协同策略，可同时改善常规荧光染料的这些特性。在传统的罗丹明中引入具有精细电子密度的喹喔啉结构，可同时产生具有振动结构和抑制扭曲分子内电荷转移（TICT）形成的新型染料，从而提高亮度和光稳定性，同时增大斯托克斯位移。新型荧光染料 YL578 的亮度和斯托克斯位移比其母体荧光染料罗丹明 B 大两倍左右。重要的是，在受激发射损耗（STED）显微镜中，YL578 衍生的探针具有更高的光稳定性，因此可以比基于碳卟啉的探针（CPY-Halo 和 580CP-Halo）多采集三倍的图像，CPY-Halo 和 580CP-Halo 被称为用于 STED 成像的光稳定荧光染料。此外，该策略很好地推广到了用于生物成像和生物传感的具有长斯托克斯位移（高达 136nm）的新型明亮和光稳定的荧光探针。
