The versatile applications of polydopamine in regenerative medicine: Progress and challenges

In recent decades, great progress has been made in regenerative medicine with the development of various functional scaffolds, many of which have been put into practical clinical applications. In this process, biomaterials with excellent properties have played an important role, such as medical metal materials, bioceramics, polymers, etc. Among them, melanin-like polymer polydopamine (PDA) attracts increasing scientific interest and shows good clinical application potential: i) PDA can be used as coating material to facilitate the loading of various bioactive molecules; ii) PDA can be applied as the main constituent material of scaffolds to optimize the performances. In this review, the preparation method and polymerization mechanism of PDA are first outlined, and then the advantages of PDA, including good biocompatibility, strong adhesion, antioxidant property, and excellent photothermal properties, are introduced. Next, this review highlights the significant applications of PDA in regenerative medicine, mainly focusing on wound healing, bone repair and regeneration, as well as different forms of tissue engineering. Finally, challenges and prospects on future clinical applications of PDA in regenerative medicine are discussed.