Spatial and mechanical properties of dilute DNA monolayers on gold imaged by AFM
Spatial and mechanical properties of dilute DNA monolayers on gold imaged by AFM
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DOI：
10.1021/jp0261657
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发表时间：
2003-04-17
影响因子：
3.3
通讯作者：
Tuite, E
中科院分区：
文献类型：
--
作者：
Erts, D;Polyakov, B;Tuite, E
通过一步共组装链烷硫醇-共轭DNA和巯基己醇（MCH）的混合单分子膜，在Au（111）表面形成了空间分布的DNA寡聚体阵列。轻敲模式的原子力显微镜被用来可视化的DNA分子在表面上的分布，并研究单个分子的机械性能。DNA包被密度随包被液中DNA寡聚体与MCH摩尔分数的增加而非线性增加。对于在空气中成像，其中表面被涂上一层薄薄的水，AFM针尖和单层上的不同结构之间的相互作用根据轻敲幅度、设定点比率和针尖形状在吸引力和排斥力之间变化。发现双链体和单链DNA分子都从表面近似垂直向上延伸。
Spatially distributed DNA oligomer arrays on Au(111) surfaces were created by one-step co-assembly of mixed monolayers of alkanethiol-conjugated DNA and mercaptohexanol (MCH). Tapping-mode AFM was used to visualize the distribution of DNA molecules on the surface and to study the mechanical properties of individual molecules. The DNA coating density increased nonlinearly with increasing mole fraction of DNA oligomer to MCH in the coating solution. For imaging in air, where surfaces are coated with a thin layer of water, the interaction between the AFM tip and the different structures on the monolayer varies between attractive and repulsive depending on the tapping amplitude, set-point ratio, and tip shape. It was found that both duplex and single-stranded DNA molecules extend approximately vertically upward from the surface.