Department of Physics and Sungkyunkwan Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University, Suwon 16419, Korea.
Department of Physics, Inha University, Incheon 22212, Korea.
Colloids Surf B Biointerfaces. 2018 Jul 1;167:197-205. doi: 10.1016/j.colsurfb.2018.04.023. Epub 2018 Apr 6.
DNA is one of the most propitious biomaterials for use in nanoscience and nanotechnology because of its exceptional characteristics, i.e. self-assembly and sequence-programmability. In this study, we fabricate sequence-designed double-crossover (DX) DNA lattices and naturally available salmon DNA (SDNA) thin films modified with the transition metal ion Mn. Phase transition of DX DNA lattices from crystalline to amorphous form controlled by varying the concentration of Mn is discussed and a critical transition concentration ([Mn]) is estimated. In addition, the electrical, optical, and magnetic properties of Mn-modified SDNA thin films including current, absorbance, photoluminescence, the X-ray photoelectron spectrum, and magnetization are studied to understand their conductivity, binding modes, energy transfer characteristics, chemical composition, and magnetism. Interestingly, the physical values such as the maximum current and photoluminescence, and the minimum absorbance, occur at around [Mn] =4 mM, which may be due to the optimal incorporation of Mn into the SDNA. The magnetization and susceptibility of SDNA thin films with Mn, served as magnetic dipoles, are studied under different temperature and magnetic field. The magnetization of SDNA thin films with [Mn] shows an S-shaped curve, indicating ferromagnetism.
DNA 是纳米科学和纳米技术中最有前途的生物材料之一，因为它具有独特的特性，如自组装和序列可编程性。在这项研究中，我们制备了序列设计的双交叉（DX）DNA 晶格和天然存在的鲑鱼 DNA（SDNA）薄膜，并用过渡金属离子 Mn 进行了修饰。通过改变 Mn 的浓度来讨论 DX DNA 晶格从结晶态到非晶态的相变，并估计了一个临界转变浓度([Mn])。此外，我们还研究了 Mn 修饰的 SDNA 薄膜的电学、光学和磁学性质，包括电流、吸收率、光致发光、X 射线光电子能谱和磁化强度，以了解它们的电导率、结合模式、能量转移特性、化学组成和磁性。有趣的是，最大电流和光致发光以及最小吸收率等物理值出现在[Mn]≈4mM 左右，这可能是由于 Mn 被最佳地掺入到 SDNA 中。我们还研究了作为磁偶极子的 Mn 掺杂 SDNA 薄膜在不同温度和磁场下的磁化和磁化率。Mn 含量为[Mn]的 SDNA 薄膜的磁化强度呈现 S 形曲线，表明具有铁磁性。
