Center for Biological Physics, Arizona State University, Tempe, AZ, 85287, USA.
Department of Physics, Arizona State University, Tempe, AZ, 85287, USA.
Nat Commun. 2019 Aug 14;10(1):3662. doi: 10.1038/s41467-019-11574-2.
Fluorescence correlation spectroscopy (FCS), is a widely used tool routinely exploited for in vivo and in vitro applications. While FCS provides estimates of dynamical quantities, such as diffusion coefficients, it demands high signal to noise ratios and long time traces, typically in the minute range. In principle, the same information can be extracted from microseconds to seconds long time traces; however, an appropriate analysis method is missing. To overcome these limitations, we adapt novel tools inspired by Bayesian non-parametrics, which starts from the direct analysis of the observed photon counts. With this approach, we are able to analyze time traces, which are too short to be analyzed by existing methods, including FCS. Our new analysis extends the capability of single molecule fluorescence confocal microscopy approaches to probe processes several orders of magnitude faster and permits a reduction of photo-toxic effects on living samples induced by long periods of light exposure.
荧光相关光谱学（FCS）是一种广泛使用的工具，通常用于体内和体外应用。虽然 FCS 提供了对扩散系数等动态量的估计，但它需要高信噪比和长时间迹线，通常在分钟范围内。原则上，同样的信息可以从微秒到秒的长时间迹线中提取；然而，缺少适当的分析方法。为了克服这些限制，我们从直接分析观察到的光子计数开始，采用了受贝叶斯非参数学启发的新工具。通过这种方法，我们能够分析时间迹线，这些时间迹线太短，无法用现有的方法（包括 FCS）进行分析。我们的新分析扩展了单分子荧光共焦显微镜方法的能力，以探测快几个数量级的过程，并减少了长时间光照对活样本产生的光毒性效应。
