Plasma bias homopolar sputtering technology and its application to enhance bioactivity of polyetheretherketone surface

Numerous strategies have been developed to deposit metal-based films on biomedical implants to improve their performances. As a promising strategy, vacuum plasma plating technology can introduce many bioactive metals on the implant surface and achieve strong interfacial bonding. However, there are still limitations in the surface modification of a non-conductive matrix. Here, a simple and universal plasma-based technique termed plasma bias homopolar sputtering (PBHS) was presented to modify the insulating and conductive materials. The technical principles and characteristics of PBHS were comprehensively studied. As a demonstration, the Fe-based film was prepared on the surface of an insulating polyetheretherketone (PEEK) by PBHS to improve its biological performance. The as-prepared Fe-based film exhibited low elasticity modulus and good hydrophilicity, enhancing the adhesion, proliferation, and osteogenic differentiation of rat bone marrow mesenchymal stem cells. This work provides a simple and universal technique for the preparation of metal-based films, holding great potential for the surface modification of biomedical implants.