Polymer coatings on magnesium-based implants for orthopedic applications

Nowadays, the need for bio-implants, which can gradually degrade after fulfilling the therapeutic tasks is continuously increasing. Under such situation, magnesium (Mg) and its alloys have been proposed and intensively studied as the new-generation medical implants due to their favorable biodegradability and biocompatibility. However, their swift corrosion in physiological environments can always cause an early fracture and further the surgical failure, greatly hindering their broad applications. Therefore, great efforts have been made to alter the degradation behaviors of Mg-based implants. Biodegradable polymeric surface coatings have been revealed to be a straightforward and effective strategy for retarding the fast degradation and improving the bioactivity of Mg and its alloys. This article reviews the recent progress of polymer-based coatings on Mg substrates, regarding the coating strategies, coating properties, and their performance in corrosive protection and biocompatibility promotion via in vitro as well as some in vivo models. The specific pros and cons of different polymeric coatings are also discussed. Finally, we put forward some perspectives on the future direction of polymeric coatings on biomedical Mg-based implants to better adapt to clinical trials.

Automated summary

This article reviews the recent progress of polymer-based coatings on Mg substrates, focusing on coating strategies, properties, and their performance in corrosion protection and biocompatibility promotion. The specific pros and cons of different polymeric coatings are also discussed. Additionally, some perspectives on the future direction of polymeric coatings on biomedical Mg-based implants are provided.