State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, Jiangsu, China.
School of Materials Science and Engineering, Nanjing Institute of Technology, Nanjing, 211167, China.
Biomolecules. 2020 May 26;10(6):814. doi: 10.3390/biom10060814.
DNA is a very useful molecule for the programmed self-assembly of 3D (three dimension) nanoscale structures. The organised 3D DNA assemblies and crystals enable scientists to conduct studies for many applications such as enzymatic catalysis, biological immune analysis and photoactivity. The first self-assembled 3D DNA single crystal was reported by Seeman and his colleagues, based on a rigid triangle tile with the tile side length of two turns. Till today, successful design of 3D single crystals by means of programmed self-assembly are countable, and still remain as the most challenging task in DNA nanotechnology, due to the highly constrained conditions for rigid tiles and precise packing. We reported here the use of small circular DNA molecules instead of linear ones as the core triangle scaffold to grow 3D single crystals. Several crystallisation parameters were screened, DNA concentration, incubation time, water-vapour exchange speed, and pH of the sampling buffer. Several kinds of DNA single crystals with different morphologies were achieved in macroscale. The crystals can provide internal porosities for hosting guest molecules of Cy3 and Cy5 labelled triplex-forming oligonucleotides (TFOs). Success of small circular DNA molecules in self-assembling 3D single crystals encourages their use in DNA nanotechnology regarding the advantage of rigidity, stability, and flexibility of circular tiles.
DNA 是一种非常有用的分子，可用于程序化自组装三维（3D）纳米结构。有组织的 3D DNA 组装体和晶体使科学家能够进行许多应用的研究，如酶催化、生物免疫分析和光活性。第一个自组装的 3D DNA 单晶是由 Seeman 和他的同事报道的，基于刚性三角形瓦片，瓦片边长为两圈。直到今天，通过程序化自组装成功设计 3D 单晶的例子还屈指可数，这仍然是 DNA 纳米技术中最具挑战性的任务，因为刚性瓦片和精确包装的条件要求非常高。我们在这里报告了使用小圆形 DNA 分子代替线性分子作为核心三角形支架来生长 3D 单晶。筛选了几个结晶参数，包括 DNA 浓度、孵育时间、水蒸汽交换速度和采样缓冲液的 pH 值。在宏观尺度上获得了几种具有不同形态的 DNA 单晶。这些晶体可以为 Cy3 和 Cy5 标记的三链形成寡核苷酸（TFO）的客体分子提供内部孔隙。小圆形 DNA 分子在自组装 3D 单晶中的成功应用鼓励它们在 DNA 纳米技术中使用，因为圆形瓦片具有刚性、稳定性和灵活性的优势。
