The visual detection of mitochondrial viscosity is of considerable significance in that it is associated with various cellular functions. Herein, a novel red-emitting viscosity probe YD-Mito constructed by linking phenylamine derivatives and benzo[e]indolium through a C–C double bond has been designed and synthesized. It was found that YD-Mito exhibited a special response to viscosity accompanying with a sharp fluorescence enhancement (20-fold) at 620 nm. Importantly, YD-Mito can precisely localized in mitochondria independent from membrane potential and visualized the mitochondrial viscosity. Therefore, probe YD-Mito could provide a powerful tool for the determination of mitochondrial viscosity.

线粒体粘度的视觉检测具有重要意义，因为它与各种细胞功能有关。在这里，已经设计并合成了一种新型的发红粘度探针YD-Mito，该探针是通过C-C双键连接苯胺衍生物和苯并[e]吲哚而构建的。发现YD-Mito对粘度表现出特殊的响应，同时在620 nm处荧光急剧增强（20倍）。重要的是，YD-Mito可以独立于膜电位而精确定位在线粒体中，并可视化线粒体粘度。因此，探针YD-Mito可以为测定线粒体粘度提供强大的工具。