Super-resolution microscopy enables imaging of structures smaller than the diffraction limit. Single-molecule localization microscopy methods, such as photoactivation localization microscopy and stochastic optical reconstruction microscopy, reconstruct images by plotting the centroids of fluorescent point sources from a series of frames in which only a few molecules are fluorescing at a time. These approaches require simpler instrumentation than methods that depend on structured illumination and thus are becoming widespread. The functionalized rhodamine derivative reported in this paper spontaneously converts between a bright and dark state due to pH-dependent cyclization. At pH 7, less than 0.5% of the dye molecules are fluorescent at any given time. Blinking occurs on time scales of seconds to minutes and can therefore be used for single-molecule localization microscopy without sample treatment or activation. The dye is bright and straightforward to use, and it is easy to synthesize and functionalize. Thus, it has potential to become a new and powerful addition to the toolset for super-resolution imaging.

中文翻译：

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罗丹明衍生的具有固有闪烁行为的荧光染料，用于超高分辨率成像

超分辨率显微镜可以对小于衍射极限的结构进行成像。单分子定位显微镜方法（例如光激活定位显微镜和随机光学重建显微镜）通过绘制一系列帧中每个点仅发出荧光的荧光点源的质心，来重建图像。这些方法比依赖于结构化照明的方法需要更简单的仪器，因此变得越来越普遍。由于pH依赖性环化作用，本文报道的功能化罗丹明衍生物自发地在亮状态和暗状态之间转换。在pH值为7时，在任何给定时间，不到0.5％的染料分子是荧光的。闪烁发生在数秒至数分钟的时间范围内，因此可用于单分子定位显微镜检查，而无需样品处理或活化。该染料光亮且易于使用，并且易于合成和功能化。因此，它有可能成为超分辨率成像工具集的新的强大功能。