Recent advances in zwitterionic polymers-based non-fouling coating strategies for biomedical applications

Biological contamination seriously restricts the development and application of medical devices, causing severe health threats and economic losses. Non-specific protein adhesion is generally considered to be the first step in biological contamination, and it is well acknowledged that hydrophilic surfaces can effectively reduce protein adsorption. Based on this principle, many anti-biofouling materials have been developed. In recent years, zwitterionic polymers with ultra-low protein adsorption and excellent biocompatibility have made them a research hotspot for the new generation of antifouling materials and attracted great attention in biomedical applications. The repeating unit carries a pair of opposite charges, and the whole molecule is electrically neutral, showing super-hydrophilic properties. Coating strategies are considered to be a promising solution to the biofouling of medical devices due to their low impact on substrates and their ability to adapt to a variety of complex surfaces. Therefore, the zwitterionic-based coating layer is the most effective way and promising candidate to solve biological contamination. In this review, we summarized the formation process of biological contamination, antifouling surface properties, up-to-date zwitterionic monomers, the strategies for non-fouling coating preparation, and their applications in biomedical fields.