Shi Wenying, Jia Yankun, Xu Simin, Li Zhixiong, Fu Yi, Wei Min, Shi Shuxian
State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology , Beijing 100029, P. R. China.
Langmuir. 2014 Nov 4;30(43):12916-22. doi: 10.1021/la502968z. Epub 2014 Oct 20.
A highly oriented film was fabricated by layer-by-layer self-assembly of DNA and MgAl-layered double hydroxide nanosheets, and its application in chiroptical switch was demonstrated via intercalation and deintercalation of an achiral molecule into the DNA cavity. DNA molecules are prone to forming an ordered and dispersive state in the interlayer region of rigid layered double hydroxide (LDH) nanosheets as confirmed by scanning electron microscopy and atomic force microscopy. The induced chiroptical ultrathin film (UTF) is achieved via the intercalation of an achiral chromophore [5,10,15,20-tetrakis(4-N-methylpyridyl)porphine tetra(p-toluenesulfonate) (TMPyP)] into the spiral cavity of DNA stabilized in the LDH matrix [denoted as TMPyP-(DNA/LDH)20]. Fluorescence and circular dichroism spectroscopy are utilized to testify the intercalation of TMPyP into (DNA/LDH)20 UTF that involves two steps: the electrostatic binding of TMPyP onto the surface of (DNA/LDH)20 followed by intercalation into base pairs of DNA. In addition, the TMPyP-(DNA/LDH)20 UTF exhibits good reversibility and repeatability in induced optical chirality, based on the intercalation and deintercalation of TMPyP by alternate exposure to HCl and NH3/H2O vapor, which can be potentially used as a chiroptical switch in data storage.
通过DNA与MgAl层状双氢氧化物纳米片的逐层自组装制备了一种高度取向的薄膜，并通过将一种非手性分子插入和脱插入DNA腔来证明其在手性光学开关中的应用。扫描电子显微镜和原子力显微镜证实，DNA分子易于在刚性层状双氢氧化物（LDH）纳米片的层间区域形成有序且分散的状态。通过将一种非手性发色团[5,10,15,20-四（4-N-甲基吡啶基）卟啉四（对甲苯磺酸盐）（TMPyP）]插入稳定在LDH基质中的DNA螺旋腔中，获得了诱导手性超薄膜（UTF）[表示为TMPyP-(DNA/LDH)20]。利用荧光光谱和圆二色光谱来证实TMPyP插入(DNA/LDH)20 UTF，这涉及两个步骤：TMPyP与(DNA/LDH)20表面的静电结合，随后插入DNA的碱基对中。此外，基于通过交替暴露于HCl和NH3/H2O蒸汽实现TMPyP的插入和脱插入，TMPyP-(DNA/LDH)20 UTF在诱导光学手性方面表现出良好的可逆性和可重复性，其有可能用作数据存储中的手性光学开关。
