Zwitterionic Biomaterials
Qingsi Li, Chiyu Wen, Jing Yang, Xianchi Zhou, Yingnan Zhu, Jie Zheng, Gang Cheng, Jie Bai, Tong Xu, Jian Ji, Shaoyi Jiang, Lei Zhang, Peng Zhang
Abstract
The term "zwitterionic polymers" refers to polymers that bear a pair of oppositely charged groups in their repeating units. When these oppositely charged groups are equally distributed at the molecular level, the molecules exhibit an overall neutral charge with a strong hydration effect via ionic solvation. The strong hydration effect constitutes the foundation of a series of exceptional properties of zwitterionic materials, including resistance to protein adsorption, lubrication at interfaces, promotion of protein stabilities, antifreezing in solutions, etc. As a result, zwitterionic materials have drawn great attention in biomedical and engineering applications in recent years. In this review, we give a comprehensive and panoramic overview of zwitterionic materials, covering the fundamentals of hydration and nonfouling behaviors, different types of zwitterionic surfaces and polymers, and their biomedical applications.