The advances in zwitterionic materials and their biomedical applications

In recent years, zwitterionic materials have been widely used in biomedical and nanomedical materials due to their unique structure in which the molecule is electrically neutral with equal positive and negative charge. This kind of material could form a thick hydration layer by the electrostatic effect, prevent contamination, and show wide applications in biomedical and life science fields, such as resisting non-specific protein adsorption, biofilm, thrombosis formation, and so on. Most importantly, the diversity of functional groups has made it more convenient for surface modification and further utilization, creating multifunctional materials for various applications. This review summarized the up-to-date zwitterionic materials, including the conventional and novel zwitterionic materials and their structural characteristics, as well as the applications in blood-contacting and implantable devices, antibacterial coatings, wound dressings, drug-targeted carriers, and smart wearable biosensors, especially in the biomedical and clinical uses. New discoveries, existing challenges, and the commercial status of zwitterionic materials are also outlined, and their future opportunities and development perspectives as new novel biomaterials are demonstrated.