Division of Physical Biology and Bioimaging Center, Shanghai Synchrotron Radiation Facility, CAS Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, University of the Chinese Academy of Sciences, Shanghai, 201800, China.
Jiading District Central Hospital, Shanghai, 201800, China.
Chembiochem. 2019 Jun 14;20(12):1508-1513. doi: 10.1002/cbic.201800727. Epub 2019 Apr 15.
One-dimensional nanotubes are of considerable interest in materials and biochemical sciences. A particular desire is to create DNA nanotubes with user-defined structural features and biological relevance, which will facilitate the application of these nanotubes in the controlled release of drugs, templating of other materials into linear arrays and the construction of artificial membrane channels. However, little is known about the structures of assembled DNA nanotubes in solution. Here we report an in situ exploration of segmented DNA nanotubes, composed of multiple units with set length distributions, by using synchrotron small-angle X-ray scattering (SAXS). Through joint experimental and theoretical studies, we show that the SAXS data are highly informative in the context of heterogeneous mixtures of DNA nanotubes. The structural parameters obtained by SAXS are in good agreement with those determined by atomic force microscopy (AFM), transmission electron microscopy (TEM), and dynamic light scattering (DLS). In particular, the SAXS data revealed important structural information on these DNA nanotubes, such as the in-solution diameters (≈25 nm), which could be obtained only with difficulty by use of other methods. Our results establish SAXS as a reliable structural analysis method for long DNA nanotubes and could assist in the rational design of these structures.
一维纳米管在材料和生物化学科学中具有相当大的兴趣。人们特别希望能够创建具有用户定义的结构特征和生物学相关性的 DNA 纳米管，这将有助于这些纳米管在药物的控制释放、其他材料的线性阵列模板化和人工膜通道的构建等方面的应用。然而，对于溶液中组装的 DNA 纳米管的结构，人们知之甚少。在这里，我们通过同步辐射小角 X 射线散射（SAXS）报告了由多个具有设定长度分布的单元组成的分段 DNA 纳米管的原位研究。通过实验和理论研究，我们表明 SAXS 数据在 DNA 纳米管的不均匀混合物的背景下具有高度的信息量。通过 SAXS 获得的结构参数与原子力显微镜（AFM）、透射电子显微镜（TEM）和动态光散射（DLS）确定的参数非常吻合。特别是，SAXS 数据揭示了这些 DNA 纳米管的重要结构信息，例如溶液中的直径（≈25nm），这只能通过其他方法很难获得。我们的结果确立了 SAXS 作为长 DNA 纳米管的可靠结构分析方法，并有助于这些结构的合理设计。
