Unique Role of Arginine in Positively‐Charged Surface for Promotion of Antibacterial and Osteogenetic Capabilities

Abstract Orthopedic implants made of titanium and titanium alloys are vulnerable to invasion of pathogenic bacteria and hence, it is desirable to endow implants with the antibacterial capability to mitigate postsurgical infection and other undesirable side‐effects. In this study, arginine is combined with polyhexamethylene biguaidine hydrochloride (PHMB) to fabricate an antibacterial coating on titanium samples. As arginine with the guanidinium form is similar to PHMB, the coating is positively‐charged and delivers excellent antibacterial performance due to the high surface potential. Furthermore, arginine is a natural α‐amino acid being friendlier to tissues than PHMB and the coating delivers good osteogenetic performance in vitro and in vivo in addition to a low level of inflammatory response. The combination of cationic arginine and PHMB enhances the antibacterial and osteogenetic functions simultaneously and suggests clinical potential.