Nanomaterials: The New Antimicrobial Magic Bullet

Abstract

Bacterial infections are a significant cause of mortality and morbidity worldwide, despite decades of use of numerous existing antibiotics and constant efforts by researchers to discover new antibiotics. The emergence of infections associated with antibiotic-resistant bacterial strains, has amplified the pressure to develop additional bactericidal therapies or new unorthodox approaches that can deal with antimicrobial resistance. Nanomaterial-based strategies, particularly those that do not rely on conventional small-molecule antibiotics, offer promise in part due to their ability to dodge existing mechanisms used by drugresistant bacteria. Therefore, the use of nanomaterial-based formulations has attracted attention in the field of antibiotic therapy. In this Review, we highlight novel and emerging nanomaterial-based formulations along with details about the mechanisms by which nanoparticles can target bacterial infections and antimicrobial resistance. A detailed discussion about types and the activities of nanoparticles is presented, along with how they can be used as either delivery systems or as inherent antimicrobials, or a combination of both. Lastly, we highlight some toxicological concerns for the use of nanoparticles in antibiotic therapies.

Metals to combat antimicrobial resistance

“…The use of metal complexes as adjuvants or potentiators, in combination with antibiotics or other biologically active compounds, is another fertile field of research, but beyond the scope of this Review. A significant body of research has been published on the use of nanoparticles as antimicrobial agents and has been reviewed elsewhere 19 , 20 . Finally, for metal-based antifungal compounds, we refer to the recent review by Lin et al 21 .…”

Nanobiotics against antimicrobial resistance: harnessing the power of nanoscale materials and technologies

“…Length and breadth of nanotubes can extend the release of given antimicrobial. Large specific surface area of NPs increases the prospect of closeness, contact, and interaction with microbial membrane [56,57] Shapes of nanomaterials are the basis of wavering degrees of damage to pathogens through periplasmic enzymes. For example, ZnONPs of various shapes (sphere, pyramid, and plate) exhibit varied photocatalytic activities with β-galactosidase leading to functional and conformational change in the enzyme [58].…”

Strategies to Mitigate and Treat Orthopaedic Device-Associated Infections

“…In the context of infection control, antimicrobial nanomaterials, nanosized drug carriers and nanostructured surfaces are of particular focus because they offer the prospect to increase targeting and eliciting multiple mechanisms simultaneously to combat microbes, thereby decreasing the likelihood of resistance developing [ 200 , 201 ]. However, the toxicity profile associated with long-term exposure to many nanosized materials and drug carriers needs to be demonstrated, particularly if intended for repeated use [ 202 ]. Bactericidal nanostructuring of materials has emerged as a trend in nanoscale approaches to infection control on the surface of implants and is discussed in Section 7 .…”

“…However, many of these novel technologies and approaches are at an earlier stage in their development and require further investigation. Further studies are required to address challenges including toxicological concerns associated with the use of nanotechnology [ 202 ], and further exploration of the potential microbial resistance to nanomaterials and nano-engineered surfaces is warranted over timeframes that approximate their usage [ 268 ]. Studies have been predominantly conducted in vitro, with fewer in vivo studies [ 201 ].…”