Development of Noncytotoxic Chitosan–Gold Nanocomposites as Efficient Antibacterial Materials

Abstract

This work describes the synthesis and characterization of noncytotoxic nanocomposites either colloidal or as films exhibiting high antibacterial activity. The biocompatible and biodegradable polymer chitosan was used as reducing and stabilizing agent for the synthesis of gold nanoparticles embedded in it. Herein, for the first time, three different chitosan grades varying in the average molecular weight and deacetylation degree (DD) were used with an optimized gold precursor concentration. Several factors were analyzed in order to obtain antimicrobial but not cytotoxic nanocomposite materials. Films based on chitosan with medium molecular weight and the highest DD exhibited the highest antibacterial activity against biofilm forming strains of Staphylococcus aureus and Pseudomonas aeruginosa. The resulting nanocomposites did not show any cytotoxicity against mammalian somatic and tumoral cells. They produced a disruptive effect on the bacteria wall while their internalization was hindered on the eukaryotic cells. This selectivity and safety make them potentially applicable as antimicrobial coatings in the biomedical field.

Water-stable cellulose fiber foam with antimicrobial properties for bio based low-density materials

“…Chitosan has primary amine groups on a polysaccharide chain that provide the polymer with its positive charge and antimicrobial properties (Tegl et al 2015). A great advantage of chitosan compared to other antimicrobial polymers is that chitosan is biocompatible and nontoxic for mammalian cells (Regiel-Futyra et al 2015). …”

Chitosan biopolymer functionalized gold nanoparticles with controlled cytotoxicity and improved antifilarial efficacy

“…In this circumstance, surface functionalization of GNPs may be planned and executed in a more effective way for betterment of bioactivity. One such functionalization can be with chitosan, which enables its efficient interaction and permeation of cellular membranes, providing an effective adjuvant [15][16][17][18][19][20]. As both GNPs and chitosan have been shown to have low toxicity and high biocompatibility, their composite material should also be less cytotoxic and biocompatible.…”

N-Heterocyclic molecule-capped gold nanoparticles as effective antibiotics against multi-drug resistant bacteria

“…1,2,27 Antibiotics-modified Au NPs showed enhancement of antibacterial activity compared to the constituent antibiotics alone. [30][31][32][33] But they are often ineffective when encountering drug-resistant bacteria. To control drugresistant bacteria efficaciously, our group has explored a series of Au NP based antimicrobial agents without using traditional, small organic-molecule based antibiotics.…”