Le Gratiet Aymeric, Marongiu Riccardo, Diaspro Alberto
Nanoscopy and NIC@IIT, Istituto Italiano di Tecnologia, Via Enrico Melen 83, 16152 Genova, Italy.
Department of Physics, University of Genoa, Via Dodecaneso 33, 16146 Genova, Italy.
Polymers (Basel). 2020 Oct 21;12(10):2428. doi: 10.3390/polym12102428.
Circular Intensity Differential Scattering (CIDS) provides a differential measurement of the circular right and left polarized light and has been proven to be a gold standard label-free technique to study the molecular conformation of complex biopolymers, such as chromatin. In early works, it has been shown that the scattering component of the CIDS signal gives information from the long-range chiral organization on a scale down to 1/10th-1/20th of the excitation wavelength, leading to information related to the structure and orientation of biopolymers in situ at the nanoscale. In this paper, we review the typical methods and technologies employed for measuring this signal coming from complex macro-molecules ordering. Additionally, we include a general description of the experimental architectures employed for spectroscopic CIDS measurements, angular or spectral, and of the most recent advances in the field of optical imaging microscopy, allowing a visualization of the chromatin organization in situ.
圆强度差散射（CIDS）提供了圆偏振光左右分量的差分测量，并且已被证明是研究复杂生物聚合物（如染色质）分子构象的无标记金标准技术。在早期的研究中，已经表明CIDS信号的散射分量能够提供从激发波长的1/10至1/20尺度上的长程手性组织信息，从而获得与纳米尺度下生物聚合物原位结构和取向相关的信息。在本文中，我们回顾了用于测量来自复杂大分子有序排列信号的典型方法和技术。此外，我们还对用于光谱CIDS测量（角度或光谱）的实验架构以及光学成像显微镜领域的最新进展进行了一般性描述，从而能够对染色质原位组织进行可视化。
