Chitosan‐capped silver nanoparticles: A comprehensive study of polymer molecular weight effect on the reaction kinetic, physicochemical properties, and synergetic antibacterial potential

Abstract

The search for novel efficient antibacterial agents is attracting a great attention due to the unregulated use of common antibiotics and development of multidrugresistant bacteria strains. This paper proposes an eco-friendly approach to obtain stable chitosan-capped silver nanoparticles with controlled physicochemical and biological properties using reducing and stabilizing capacity of chitosan. The study of the influence of chitosan characteristics on the kinetic of Ag + reduction showed that an increase in polysaccharide molecular weight led to a decrease in their reducing ability. The synthesized silver nanoparticles were characterized by UV and FTIR spectroscopy, TEM, XRD, DLS. The relationships between physicochemical characteristics of the formed silver nanoparticles and the type of used chitosan, as well as synthesis temperature, were determined. It has been demonstrated that spherically-shaped (13-27 nm) and positively-charged (zeta-potential 26.1-29.5 mV) silver nanoparticles with a single symmetric SPR band at 408-418 nm are stable during 6 months in a colloidal form, and can be produced with the assistance of low-molecular weight chitosan (20-30 kDa) at 95 C. The synthesized silver nanoparticles enhanced the antibacterial activity of kanamycin and ampicillin against both gram-negative and gram-positive bacteria. These results revealed the prospects for the application of chitosan-capped silver nanoparticles to create new effective antibacterial systems (gels, films, etc).

The Use of Capping Agents in the Stabilization and Functionalization of Metallic Nanoparticles for Biomedical Applications

“…[21] These characteristics have motivated its extensive use, being not only a biocompatible coating, but also an adjuvant for therapies with MNPs. [114] Gold nanoparticles capped with CS showed good stability and increased in vitro biological activity, [115] similar results were obtained for silver NPs, [116] while chitosan-stabilized iron and zinc oxides nanoparticles have been also reported. [117,118] Another positively charged amino polymer, poly(ethylenimine) (PEI), is a frequently employed stabilizer.…”

Polyethylene glycol dictates the therapeutic response (anticancer and wound healing) of silver oxide nanomaterials

“…Electrostatic repulsion of the same types of charges over the surface of NPs avoids aggregation and promotes the stability of NPs in the suspension 54 . The increase in size also testifies the successful attachment of polymer on the surface of silver oxide NPs as it can be linked with the availability of a large number of PEG and Chitosan molecules 55 . The stability of NPs in colloidal dispersion is indicated by the value of their ζ‐potential.…”

Green Synthesis and Characterization of Silver Nanoparticles Using a Lythrum salicaria Extract and In Vitro Exploration of Their Biological Activities

“…On the other hand, the DLS analysis measured the dynamic fluctuation and velocity of particles in suspended clusters, meaning the metallic silver core and the molecules that were attached to the surface nanoparticles, which could, depending on the structure, undergo a process of solvation and expansion in solution. Therefore, the hydrodynamic diameter estimated by DLS was larger than the size estimated by TEM [ 33 , 42 , 43 ].…”