Antimicrobial nanoparticle coatings for medical implants: Design challenges and prospects

Microbial colonization, infection, and biofilm formation are major complications in the use of implants and are the predominant risk factors in implant failure. Although aseptic surgery and the administration of antimicrobial drugs may reduce the risk of infection, the systemic use of antibiotics can lead to a lack of efficacy, an increase in the risk of tissue toxicity, and the development of drug-resistant infections. To reduce implant-related infections, antimicrobial materials are increasingly being investigated and applied to implant surfaces using various methods depending on the agents and their microbicidal mechanisms. Through the development of biomaterials and nanotechnology, antimicrobial nanoparticles are becoming promising candidates for implant coatings, as their multifactorial antimicrobial mechanisms combat microbial adherence, viability, and biofilm formation. Despite their antimicrobial promise, the application of nanoparticles onto implant surfaces while retaining their antimicrobial potency faces many challenges. Herein, we review the potential and challenges associated with the design and implementation of antimicrobial nanoparticle coatings for the medical implant industry, particularly focusing on manufacturing considerations, sterilization, long-term stability, protein fouling, regulation, and safety, with a view to providing researchers the necessary tools to aid the translation of materials from the bench to the clinic.