Advances in antimicrobial and osteoinductive biomaterials

Abstract

The enormous growing problem with antibiotic resistance in pathogenic microbes is one of the greatest threats we are facing today. In the context of orthopedic applications, infections also lead to the limited healing ability of infected and defected bone. Generally, these problems are treated with a load of antibiotics or surgical intervention. Therefore, having antibacterial properties integrated with a biomaterial would reduce the time of healing and treatment, amount of antibiotic needed, and total cost. Currently, there exists several strategies and materials with the potential of tackling these challenges. Some materials with antibacterial properties currently employed are silver nanoparticles (AgNPs), cerium oxide nanoparticles (CeO2NPs), selenium nanoparticles (SeNPs), copper nanoparticles (CuNPs), antimicrobial peptides (AMPs), biopolymers (such as chitosan), and carbon nanostructures. On the other hand, osteoinductive and osteoconductive materials are important to promote bone healing and regeneration. Within this framework, materials which have been employed widely are bioactive glasses (BG), calcium phosphates (CaPs) (e.g., hydroxyapatite (HA), tricalcium Β-phosphate (Β-TCP), and biphasic calcium phosphate (BCP)), peptides, growth factors, and other elements (e.g., magnesium (Mg), zinc (Zn), strontium (Sr), silicon (Si), selenium (Se), and Cu, to name a few). Some of the current technological solutions that have been employed are, for instance, the use of a co-delivery system, where both the antibacterial and the osteoinducing agents are delivered from the same delivery system. However, this approach requires overcoming challenges with local delivery in a sustained and prolonged way, thus avoiding tissue toxicity. To address these challenges and promote novel biomaterials with dual action, sophisticated thinking and approaches have to be employed. For this, it is of the utmost importance to have a solid fundamental understanding of current technologies, bacteria behavior and response to treatments, and also a correlation between the material of use, the host tissue and bacteria. We hope by highlighting these aspects, we will promote the invention of the next generation of smart biomaterials with dual action ability to both inhibit infection and promote tissue growth.