Active delivery of antimicrobial nanoparticles into microbial cells through surface functionalization strategies

Background: Recently, the structural and behavioral changes of microorganisms have been rapidly increased. The appearance of resistant bacteria by enhancing antibiotic adaptation potentially is a significant concern for public health; thus, many efforts are needed to promote efficiency of antimicrobial substances. Surface functionalization of antimicrobial nanoparticles can improve their efficiency and diverse studies have shown their high potentials against resistant bacteria. Scope and approach: The main objective of this study was to present an overview of the effect of surface functionalization of nanoparticles on their antimicrobial activities against resistant bacteria and discuss different types of functionalization methods for improving nanoparticle functions. The common functional compounds which can be applied on the surface of antimicrobial nanoparticle are described and the current application of functionalized nanoparticles in controlling high resistant bacteria are summarized and tabulated. Key findings and conclusions: The surface functionalization of nanoparticles is an effective method in inhibition of the growth of various bacteria. Cationic polymers, small ligands, and biomolecules are the most popular functional compounds which have been successfully applied for improving the antimicrobial activities of nanoparticles through bonding with their surfaces. The changes in the surface characteristics of nanoparticles such as charge, shape, release behavior, and synergistic effects of functional agents on the nanoparticles can greatly enhance their antimicrobial efficiencies.