Modifying the composition of polyampholytes, which are comprised of charge-positive and charge-negative repeat units, directly contributes to trade-offs between charge and structure, which are externally regulated by solution pH and added salt. Here, the relative ratio of anionic and cationic comonomers is varied to tailor the stimuli-responsiveness of poly(methacrylic acid-co-N,N-diethylaminoethyl methacrylate) (P(MAA-co-DEAEMA)) brushes to changes in solution pH and an added zwitterion. These systems display a strong dependence on excess repeating units of either type and the random incorporation appears to facilitate self-neutralization of charges. Pseudo-living growth with smooth comonomer incorporation is achieved using activators regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP), creating well-defined brushes. In situ ellipsometry measurements of solvated brush thickness indicate that at low and high pH, the brushes display polyelectrolyte behavior with a strong compositional dependence, but at intermediate pH values, the brushes show the characteristic collapse attributed to self-neutralization of polyampholytes. The polyampholyte brushes maintain these patterns of behavior across all compositions and in the presence of an added zwitterion, which contributes additional hydrophobic character as evidenced by decreases in the swollen layer thicknesses. The response of the P(MAA-co-DEAEMA) brushes to the organic osmolyte betaine is consistent with its tendency to stabilize proteins and peptides in a kosmotropic fashion. These studies add perspective to efforts to manipulate sequence in polyampholytic polymers, support broader efforts to tailor interfacial soft films for applications in biotechnology and sensing, and understand aggregation and stability of biological polymers.

中文翻译：

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ARGET-ATRP合成和组成变化的聚（甲基丙烯酸-co- N，N-甲基丙烯酸N-二乙氨基乙酯）聚两性电解质刷的溶胀响应†

改变由电荷正和负电荷重复单元组成的多两性电解质的组成，直接有助于电荷和结构之间的权衡，而这种平衡由溶液的pH值和添加的盐从外部进行调节。在此，改变阴离子和阳离子共聚单体的相对比例，以调整聚（甲基丙烯酸-co -N，N-甲基丙烯酸N-二乙基氨基乙基酯）（P（MAA- co-DEAEMA））刷洗溶液pH值的变化和增加的两性离子。这些系统对任一类型的过量重复单元表现出强烈的依赖性​​，并且随机掺入似乎促进电荷的自中和。使用通过电子转移原子转移自由基聚合（ARGET ATRP）再生的活化剂，可实现清晰定义的刷子，从而实现平滑共聚单体掺入的假活性生长。原位椭圆度法测量的溶剂化刷子厚度表明，在低和高pH值下，刷子显示出具有强烈的成分依赖性的聚电解质行为，但在中等pH值下，刷子显示出归因于多两性电解质的自中和的特性塌陷。在添加的两性离子存在下，多两性离子刷在所有组合物中都保持了这些行为模式，这通过增加溶胀层的厚度证明了其附加的疏水性。P（MAA- co-DEAEMA）刷到有机渗透压甜菜碱中，这与它以趋同性方式稳定蛋白质和肽的趋势一致。这些研究为操纵多两性聚合物中的序列增加了视角，支持为在生物技术和传感中应用定制界面软膜的更广泛的努力，以及了解生物聚合物的聚集和稳定性。