New Perspectives of Using Chitosan, Silver, and Chitosan–Silver Nanoparticles against Multidrug‐Resistant Bacteria

Nanomaterials with antimicrobial activity are promising alternatives to overcome microbial resistance in medical devices. Catheters, probes, and wound dressings are among the medical devices mostly affected by microbial contamination and the formation of polymicrobial biofilms. Nanoparticles (NPs) derived from natural sources, such as chitosan nanoparticles (CsNPs), and metal‐based nanoparticles, including silver nanoparticles (AgNPs), are receiving increased interest in nanomedicine. CsNPs have been widely explored as a coating material and antimicrobial agent. AgNPs have a strong antimicrobial effect against bacteria and fungi. The nanocomposite chitosan–silver nanoparticles (Cs‐AgNPs) can be more effective against several microorganisms, including multidrug‐resistant bacteria, due to the synergistic effect between chitosan and silver. This review addresses the most used synthesis methods, including green routes, to produce CsNPs, AgNPs, and Cs–AgNPs. It also discusses physicochemical characteristics and antimicrobial properties of these NPs in medical, pharmaceutical, and biotechnological areas. Given the new challenges arising from the resistance of pathogens to commonly used antibiotics and innovations in medicine regarding the use of nanomaterials, this review examines the perspectives of using chitosan, silver, and the composite chitosan–silver nanoparticles to prevent biofilm formation. It also covers the physicochemical and antimicrobial properties of these alternative nanomaterials in medical, pharmaceutical, and biotechnological applications.