Dynamic surface coatings through the hierarchical self-assembly of responsive colloidal building blocks

通过响应性胶体构建块的分层自组装实现动态表面涂层

• 批准号: 426950009
• 负责人: Professor Dr. Andreas Fery
• 金额: --
• 依托单位: Leibniz-Institut für Polymerforschung Dresden (IPF)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/426950009?language=en
• 关键词: Dynamic; surface; coatings; through; hierarchical

The project aims at exploring a novel strategy for the assembly of polymeric coatings which show pronounced responsiveness towards changes in pH or irradiation with light while simultaneously providing a compartmentalized structure with nm feature sizes and full reversibility of structural changes. The assembly strategy uses different colloidal building blocks: either pH-responsive micelles formed from ampholytic triblock terpolymers are used or, as an alternative, spherical polyelectrolyte brushes with an ampholytic diblock copolymer corona are prepared. These building blocks allow multilayer formation via layer-by-layer electrostatic self-assembly. In both cases, the interactions between adjacent colloidal building blocks as well as with potential adsorbents on the surface can be controlled via external stimuli, i.e. switching from attractive to repulsive interactions can be realized. In that way, we aim at light- and pH-responsive materials which are capable of interacting with different systems upon adhesion or film formation. Whereas the incorporation of pH-sensitive segments in block copolymer-based multi-compartment micelles (MCMs) leads to charge-invertible nanostructures, light as external trigger is implemented by exploiting the photo-acidity of TiO2 upon irradiation. TiO2 can act as a light sensitizer, as illumination of TiO2 with light of suitable wavelength results in local pH changes, triggering changes in the charge and conformation of attached polyelectrolytes. The immobilization of colloidal building blocks on surfaces can be directly achieved from aqueous solutions using non-covalent interactions. Thus, coatings can be formed under environmentally friendly conditions on a large variety of surfaces including metals, metal-oxides or polymeric materials and with varying thickness. While our study is of fundamental nature, we envision potential applications of these coatings as switchable cell culture surfaces or switchable elements in 3D cell cultures in the future.

该项目旨在探索一种新的聚合物涂层组装策略，该聚合物涂层对pH值变化或光照射表现出明显的响应性，同时提供具有nm特征尺寸和结构变化完全可逆性的分隔结构。组装策略使用不同的胶体构建块：使用由两性三嵌段三元共聚物形成的pH响应性胶束，或者作为替代方案，制备具有两性二嵌段共聚物电晕的球形刷。这些结构单元允许通过逐层静电自组装形成多层。在这两种情况下，相邻的胶体结构单元之间的相互作用以及与表面上的潜在吸附剂的相互作用可以通过外部刺激来控制，即可以实现从吸引相互作用到排斥相互作用的切换。通过这种方式，我们的目标是能够在粘附或成膜时与不同系统相互作用的光响应和pH响应材料。而在嵌段共聚物为基础的多室胶束（MCMs）的pH敏感段的掺入导致电荷可逆的纳米结构，光作为外部触发器是通过利用光照时的光酸度的二氧化钛。TiO2可以作为光敏剂，因为用合适波长的光照射TiO2会导致局部pH值变化，从而引发附着的聚电解质的电荷和构象变化。胶体结构单元在表面上的固定可以使用非共价相互作用从水溶液直接实现。因此，涂层可以在环境友好的条件下在包括金属、金属氧化物或聚合物材料的各种表面上形成，并且具有不同的厚度。虽然我们的研究是基础性质的，但我们设想这些涂层在未来作为可切换细胞培养表面或3D细胞培养中的可切换元件的潜在应用。