Department of Biomedical Science, University of Sheffield, Sheffield, UK.
ACS Nano. 2011 Mar 22;5(3):1775-84. doi: 10.1021/nn102455z. Epub 2011 Feb 23.
Nature has the exquisite ability to design specific surface patterns and topologies on both the macro- and nanolength scales that relate to precise functions. Following a biomimetic approach, we have engineered fully synthetic nanoparticles that are able to self-organize their surface into controlled domains. We focused on polymeric vesicles or "polymersomes"; enclosed membranes formed via self-assembly of amphiphilic block copolymers in water. Exploiting the intrinsic thermodynamic tendency of dissimilar polymers to undergo phase separation, we mixed different vesicle-forming block copolymers in various proportions in order to obtain a wide range of polymersomes with differing surface domains. Using a combination of confocal laser scanning microscopy studies of micrometer-sized polymersomes, and electron microscopy, atomic force microscopy, and fluorescence spectroscopy on nanometer-sized polymersomes, we find that the domains exhibit similar shapes on both the micro- and nanolength scales, with dimensions that are linearly proportional to the vesicle diameter. Finally, we demonstrate that such control over the surface "patchiness" of these polymersomes determines their cell internalization kinetics for live cells.
大自然具有在宏观和纳米尺度上设计与精确功能相关的特定表面图案和拓扑结构的精湛能力。我们采用仿生方法，设计出能够将其表面自组装成可控区域的全合成纳米粒子。我们专注于聚合物囊泡或“聚合物囊泡”；通过两亲性嵌段共聚物在水中自组装形成的封闭膜。利用不同聚合物发生相分离的固有热力学趋势，我们以不同比例混合不同的囊泡形成嵌段共聚物，以获得具有不同表面区域的广泛聚合物囊泡。通过对微米级聚合物囊泡的共焦激光扫描显微镜研究以及对纳米级聚合物囊泡的电子显微镜、原子力显微镜和荧光光谱学的组合使用，我们发现这些区域在微观和纳米尺度上具有相似的形状，其尺寸与囊泡直径呈线性比例关系。最后，我们证明了对这些聚合物囊泡表面“斑驳”的这种控制决定了它们对活细胞的细胞内化动力学。
