Linear and cyclic poly(2-ethyl-2-oxazoline) (PEOXA) adsorbates provide excellent colloidal stability to superparamagnetic iron oxide nanoparticles (Fe_xO_y NPs) within protein-rich media. However, dense shells of linear PEOXA brushes cannot prevent weak but significant attractive interactions with human serum albumin. In contrast, their cyclic PEOXA counterparts quantitatively hinder protein adsorption, as demonstrated by a combination of dynamic light scattering and isothermal titration calorimetry. The cyclic PEOXA brushes generate NP shells that are denser and more compact than their linear counterparts, entirely preventing the formation of a protein corona as well as aggregation, even when the lower critical solution temperature of PEOXA in a physiological buffer is reached.

中文翻译：

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聚合物拓扑结构决定核壳纳米粒子上蛋白质电晕的形成。

线性和环状聚（2-乙基-2-恶唑啉）（PEOXA）吸附物为富含蛋白质的介质中的超顺磁性氧化铁纳米粒子（F _x O _y NP）提供优异的胶体稳定性。然而，线性 PEOXA 刷的致密外壳不能阻止与人血清白蛋白的微弱但显着的吸引力相互作用。相反，动态光散射和等温滴定量热法的结合证明了它们的环状 PEOXA 对应物定量地阻碍了蛋白质吸附。环状 PEOXA 刷生成的 NP 壳比线性刷更致密、更紧凑，完全防止蛋白质电晕的形成和聚集，即使达到生理缓冲液中 PEOXA 的较低临界溶液温度也是如此。