Key Laboratory of Polymer Ecomaterials , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Renmin Street 5625 , Changchun 130022 , People's Republic of China.
University of Chinese Academy of Sciences , Beijing 100039 , People's Republic of China.
Biomacromolecules. 2019 Apr 8;20(4):1655-1666. doi: 10.1021/acs.biomac.9b00026. Epub 2019 Mar 6.
OEGylation is an attractive approach to modifying poly(amino acid)s. OEG conjugation improves water-solubility of poly(amino acid)s, and confers possible thermal-responsive functionality for the conjugated poly(amino acid)s. Nevertheless, the impact of OEG architecture and the manner in which the OEG moiety interferes with the performances of poly(amino acid)s remain a work in progress. In this study, a series of new linear and Y-shaped OEG-substituted poly(glutamic acid)s were designed and synthesized. It is found that the thermoresponsive behavior of OEGylated poly(glutamic acid)s experiences steric repulsion effect, the strengths of which are architecture and length-dependent, and grows pronounced only when the number of the OEG units is ≥6. Notably, the Y-shaped architecture is able to stabilize the helicity of poly(glutamic acid) backbones, while maintaining higher α-helical conformation than its linear counterparts. In sum, our result indicate that Y-shaped architecture is more appropriate toward OEGylating poly(amino acid)s for biomedical applications.
OEG 化是一种有吸引力的方法来修饰聚（氨基酸）。OEG 缀合提高了聚（氨基酸）的水溶性，并赋予缀合的聚（氨基酸）可能的热响应功能。然而，OEG 结构的影响以及 OEG 部分干扰聚（氨基酸）性能的方式仍在研究中。在这项研究中，设计并合成了一系列新型的线性和 Y 型 OEG 取代的聚（谷氨酸）。研究发现，OEG 化聚（谷氨酸）的热响应行为经历空间排斥效应，其强度取决于结构和长度，并仅在 OEG 单元的数量≥6 时才变得明显。值得注意的是，Y 型结构能够稳定聚（谷氨酸）主链的螺旋性，同时保持比其线性对应物更高的α-螺旋构象。总之，我们的结果表明，Y 型结构更适合用于生物医学应用的 OEG 化聚（氨基酸）。
