Ion-Specific Modulation of Interfacial Interaction Potentials between Solid Substrates and Cell-Sized Particles Mediated via Zwitterionic, Super-Hydrophilic Poly(sulfobetaine) Brushes
Ion-Specific Modulation of Interfacial Interaction Potentials between Solid Substrates and Cell-Sized Particles Mediated via Zwitterionic, Super-Hydrophilic Poly(sulfobetaine) Brushes
复制标题
DOI：
10.1021/acs.jpcb.6b11540
复制
发表时间：
2017-02-16
影响因子：
3.3
通讯作者：
Tanaka, Motomu
中科院分区：
文献类型：
--
作者：
Higaki, Yuji;Froehlich, Benjamin;Tanaka, Motomu
两性离子聚合物刷吸引越来越多的关注，不仅因为它们的超亲水性，自清洁能力，而且还由于它们优异的抗静电能力。我们研究了通过密集的，均匀的聚（磺基甜菜碱）刷的界面相互作用电位的离子特定的调制。用显微干涉法对细胞大小的乳胶粒子的垂直布朗运动进行了监测，得到了有效界面相互作用势V（Δ h）和高度波动的自相关函数。电位曲率V”（Δ h）随一价盐浓度的增加而单调增加，表明电位约束的尖锐化。在CaCl2溶液中观察到相反的趋势，表明离子特异性调制无法用经典霍夫迈斯特系列解释。当粒子波动的自由磺基甜菜碱分子的存在下进行监测，在[磺基甜菜碱]的增加导致流体动力学摩擦的明显增加。这在所有其他盐溶液中从未观察到，表明磺基甜菜碱侧链的两性离子配对通过将磺基甜菜碱分子嵌入到刷层中而受到干扰。此外，聚（磺基甜菜碱）刷对人红细胞表现出非常低的V”（Δ h）和流体动力学摩擦，这似乎解释了两性离子聚合物材料的优异的血液排斥性。
Zwitterionic polymer brushes draw increasing attention not only because of their superhydrophilic, self-cleaning capability but also due to their excellent antifouling capacity. We investigated the ion-specific modulation of the interfacial interaction potential via densely packed, uniform poly(sulfobetaine) brushes. The vertical Brownian motion of a cell-sized latex particle was monitored by microinterferometry, yielding the effective interfacial interaction potentials V(Delta h) and the autocorrelation function of height fluctuation. The potential curvature V"(Delta h) exhibited a monotonic increase according to the increase in monovalent salt concentrations, implying the sharpening of the potential confinement. An opposite tendency was observed in CaCl2 solutions, suggesting that the ion specific modulation cannot be explained by the classical Hofmeister series. When the particle fluctuation was monitored in the presence of free sulfobetaine molecules, the increase in [sulfobetaine] resulted in a distinct increase in hydrodynamic friction. This was never observed in all the other salt solutions, suggesting the interference of zwitterionic pairing of sulfobetaine side chains by the intercalation of sulfobetaine molecules into the brush layer. Furthermore, poly(sulfobetaine) brushes exhibited a very low V"(Delta h) and hydrodynamic friction to human erythrocytes, which seems to explain the excellent blood repellency of zwitterionic polymer materials.