Photolithographic-based stamp technique for improving the biocompatibility of antibacterial titanium implant by dynamic clearance of antibacterial agents

Abstract

• The stamps of antibacterial complex and OGP were prepared onto UCNPs decorated Ti substrates. • The loading, releasing, and clearing of antimicrobial agents can be controlled by NIR light. • The modified Ti substrate possesses dynamic regulation for antibiosis and osteogenesis. • The prepared Ti implants has better antibacterial and bone formation ability in vivo . Antibacterial titanium implants used in orthopedic and oral tooth repair have been widely researched for reducing the occurrence of second replacement operation. Although possessing a good antibiosis effect, the traditional methods have poor biocompatibility and even may cause damage to the body. Especially for loading antibiotic, after killing pathogenic bacteria, the residual antibacterial drugs may hinder the implant-tissue binding. Here, we develop a novel strategy for Ti implant based on photolithography, which can achieve the near-infrared (NIR) light-controlled antimicrobial agents loading, releasing, and clearing. A grid-like stamp of antibacterial complex and osteogenic growth peptide (OGP) were successfully prepared onto lanthanide-doped upconverting nanoparticles (UCNPs) decorated Ti substrate by selectively flicking antimicrobial agents away and replacing them with OGP. In vitro antibacterial evaluation and cell experiments proved that the modified Ti substrate (Ti-LA/OGP) exerts excellent antibacterial ability, as well as outstanding osteoinductive abilities for osteoblasts adhesion and differentiation. When implanted in infection models, Ti-LA/OGP possesses high antibacterial property at the early stage of implantation. After the success of antibiosis, irradiated with NIR light to remove the residual antibacterial agents, the osteogenesis of Ti-LA/OGP implants can be improved obviously. Moreover, this work may provide a promising strategy for the dynamic study of orthopedic application.