Probing the diffusion of molecules has become a routine measurement across the life sciences, chemistry and physics. It provides valuable insights into reaction dynamics, oligomerisation, molecular (re-)organisation or cellular heterogeneities. Fluorescence correlation spectroscopy (FCS) is one of the widely applied techniques to determine diffusion dynamics in two and three dimensions. This technique relies on the temporal autocorrelation of intensity fluctuations but recording these fluctuations has thus far been limited by the detection electronics, which could not efficiently and accurately time-tag photons at high count rates. This has until now restricted the range of measurable dye concentrations, as well as the data quality of the FCS recordings, especially in combination with super-resolution stimulated emission depletion (STED) nanoscopy. Here, we investigate the applicability and reliability of (STED-)FCS at high photon count rates (average intensities of more ...

中文翻译：

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高光子计数率提高了超分辨率荧光涨落光谱的质量


探测分子的扩散已成为生命科学、化学和物理学领域的常规测量。它为反应动力学、寡聚、分子（重新）组织或细胞异质性提供了有价值的见解。荧光相关光谱（FCS）是广泛应用的确定二维和三维扩散动力学的技术之一。该技术依赖于强度波动的时间自相关，但迄今为止记录这些波动受到检测电子设备的限制，检测电子设备无法在高计数率下有效且准确地对光子进行时间标记。迄今为止，这限制了可测量的染料浓度范围以及 FCS 记录的数据质量，特别是与超分辨率受激发射损耗 (STED) 纳米显微镜相结合。在这里，我们研究 (STED-)FCS 在高光子计数率（平均强度更多...