Department of Chemistry, Northwestern University, Evanston, Illinois 60208, USA.
Langmuir. 2011 Feb 15;27(4):1246-50. doi: 10.1021/la103960q. Epub 2010 Nov 19.
Properties of self-assembled monolayers (SAMs) can be tailored by the curvature of the underlying surface. This is so because on a curved support the density of SAM headgroups is always smaller than that of the surface-attachment sites. This density difference increases with increasing curvature and is most pronounced for SAMs formed on nanoscopic particles. This Perspective describes systems in which nanoscale curvature causes pronounced changes in the pK(a) of acid-presenting SAMs or in the electrochemical potential of redox-active molecules (including supramolecular "switches") attached to nanoparticles. It is suggested that in nanoparticles having regions of different curvature these geometrical differences can translate into site-selective charging; such "patchy" particles could be used as building blocks of pH-sensitive assemblies.
自组装单分子层（SAMs）的性质可以通过基底表面的曲率来调节。这是因为在弯曲的基底上，SAM 头基的密度总是小于表面附着位点的密度。这种密度差随着曲率的增加而增加，对于在纳米粒子上形成的 SAM 最为明显。本文描述了纳米尺度曲率导致呈现酸的 SAM 的 pK(a)或连接到纳米粒子的氧化还原活性分子（包括超分子“开关”）的电化学势发生明显变化的系统。有人提出，在曲率不同的纳米粒子中，这些几何差异可以转化为选择性充电的位点；这种“斑驳”的粒子可以用作 pH 敏感组装体的构建块。
