Selective Colloid Transport across Planar Polymer Brushes
Selective Colloid Transport across Planar Polymer Brushes
复制标题
跨平面聚合物刷的选择性胶体传输
DOI：
10.1002/marc.202200980
复制
发表时间：
2023
影响因子：
4.6
通讯作者：
Laktionov M
中科院分区：
文献类型：
--
作者：
Laktionov M
聚合物刷子作为表面涂层具有广泛的应用前景，从基础研究到日常生活，在生物系统中也扮演着重要的角色。胶体(例如，功能纳米粒子、蛋白质、病毒)如何结合并在聚合物刷子中移动是一个重要但未被研究的问题。提出了一种平均场理论方法来分析胶体在平面聚合物刷中的结合和传输。该理论明确考虑了溶剂强度对刷子构象的影响以及胶体-聚合物亲和力对胶体结合和传输的影响。推导出胶体插入聚合物刷子的位置相关自由能，该自由能控制胶体穿过刷子的传输速度。它展示了如何调整刷子的性能以使刷子具有高度的选择性，有效地充当相对于胶体尺寸和对刷子形成聚合物的亲和力的可调闸门。同时允许高电刷渗透性和选择性的最重要的参数区域对应于当排斥和吸引对胶体插入自由能的贡献几乎抵消时的条件。这一理论应该有助于设计具有更高选择性的传感和净化设备，并更好地理解支持生物聚合物刷子功能的机制。
Polymer brushes are attractive as surface coatings for a wide range of applications, from fundamental research to everyday life, and also play important roles in biological systems. How colloids (e.g., functional nanoparticles, proteins, viruses) bind and move across polymer brushes is an important yet under‐studied problem. A mean‐field theoretical approach is presented to analyze the binding and transport of colloids in planar polymer brushes. The theory explicitly considers the effect of solvent strength on brush conformation and of colloid‐polymer affinity on colloid binding and transport. The position‐dependent free energy of the colloid insertion into the polymer brush which controls the rate of colloid transport across the brush is derived. It is shown how the properties of the brush can be adjusted for brushes to be highly selective, effectively serving as tuneable gates with respect to colloid size and affinity to the brush‐forming polymer. The most important parameter regime simultaneously allowing for high brush permeability and selectivity corresponds to a condition when the repulsive and attractive contributions to the colloid insertion free energy nearly cancel. This theory should be useful to design sensing and purification devices with enhanced selectivity and to better understand mechanisms underpinning the functions of biological polymer brushes.