Digman Michelle A, Gratton Enrico
Laboratory for Fluorescence Dynamics, Department of Biomedical Engineering, University of California, Irvine, California 92697, USA.
Annu Rev Phys Chem. 2011;62:645-68. doi: 10.1146/annurev-physchem-032210-103424.
Molecular diffusion and transport processes are fundamental in physical, chemical, and biological systems. Current approaches to measuring molecular transport in cells and tissues based on perturbation methods, e.g., fluorescence recovery after photobleaching, are invasive; single-point fluctuation correlation methods are local; and single-particle tracking requires the observation of isolated particles for relatively long periods of time. We discuss here the detection of molecular transport by exploiting spatiotemporal correlations measured among points at large distances (>1 μm). We illustrate the evolution of the conceptual framework that started with single-point fluorescence fluctuation analysis based on the transit of fluorescent molecules through a small volume of illumination. This idea has evolved to include the measurement of fluctuations at many locations in the sample using microscopy imaging methods. Image fluctuation analysis has become a rich and powerful technique that can be used to extract information about the spatial distribution of molecular concentration and transport in cells and tissues.
分子扩散和传输过程在物理、化学和生物系统中是基础性的。当前基于微扰方法（例如光漂白后的荧光恢复）测量细胞和组织中分子传输的方法具有侵入性；单点涨落相关方法是局部性的；而单粒子追踪需要在相对较长的时间内观察孤立的粒子。我们在此讨论通过利用在远距离（>1μm）各点之间测量到的时空相关性来检测分子传输。我们阐述了概念框架的演变，该框架始于基于荧光分子通过小体积照明区域的通过情况进行的单点荧光涨落分析。这个想法已经发展到包括使用显微镜成像方法测量样品中多个位置的涨落情况。图像涨落分析已成为一种丰富且强大的技术，可用于提取有关细胞和组织中分子浓度和传输的空间分布信息。
