中文摘要：

圆二色谱（Circular dichroism，CD）技术是DNA结构研究的有力工具之一。目前，一般的CD光谱仪只可获得190nm波长以上的CD信号，并且在190-220nm波长范围内因受到空气、溶剂、缓冲液及盐离子浓度等的影响而噪音很大，并无太大的实用价值。同步辐射圆二色谱技术（Synchrotron radiation circular dichroism，SRCD）的发展，使得在真空紫外（Vacuum ultraviolet，VUV）区获得DNA结构的CD信号成为可能，目前已成为研究DNA结构的一种新的有力手段。本文首先介绍了SRCD技术的原理和特点，尤其是在DNA结构研究中的优势，然后概述了DNA的结构及影响CD信号的因素，最后以几种典型的DNA结构为例分析了它们的SRCD特征图谱。

英文摘要：

Circular dichroism （CD） spectroscopy is one of the powerful tools for DNA structure research. Currently, the general CD spectrometer can only obtain the CD signal with wavelength above 190 nm, and the noise is very high with the wavelength range of 190-220 nm because of the influences from the air, the solvents, and the salt ion concentration of the buffer, etc., making it have not much practical value. The development of the synchrotron radiation circular dichroism （SRCD） makes it possible to obtain the CD signal of the DNA structure in the region of the vacuum ultraviolet （VUV）. And now it becomes a new powerful tool for studying the DNA structure. This work firstly introduces the principle and features of SRCD technique, especially its advantages in the DNA structure research. Then the DNA structures and the factors affecting the CD signal are also reviewed. Finally, some typical DNA structures are taken as samples to analyze their SRCD spectrum.