Antibacterial Effect of Chitosan–Gold Nanoparticles and Computational Modeling of the Interaction between Chitosan and a Lipid Bilayer Model

Abstract

Pathogenic bacteria have the ability to develop antibiotic resistance mechanisms. Their action consists mainly in the production of bacterial enzymes that inactivate antibiotics or the appearance of modifications that prevent the arrival of the drug at the target point or the alteration of the target point itself, becoming a growing problem for health systems. Chitosan–gold nanoparticles (Cs-AuNPs) have been shown as effective bactericidal materials avoiding damage to human cells. In this work, Cs-AuNPs were synthesized using chitosan as the reducing agent, and a systematic analysis of the influence of the synthesis parameters on the size and zeta potential of the Cs-AuNPs and their UV-vis spectra was carried out. We used a simulation model to characterize the interaction of chitosan with bacterial membranes, using a symmetric charged bilayer and two different chitosan models with different degrees of the chitosan amine protonation as a function of pH, with the aim to elucidate the antibacterial mechanism involving the cell wall disruption. The Cs-AuNP antibacterial activity was evaluated to check the simulation model.

Ceftriaxone Mediated Synthesized Gold Nanoparticles: A Nano-Therapeutic Tool to Target Bacterial Resistance

“…Among the different inorganic nanoparticles, gold nanoparticles (GNPs) are of major interest in diverse research fields such as therapeutics, antimicrobials, catalysis, and biomolecular detection [16][17][18]. A two-fold increase in antibiotic activity was observed when ampicillin was conjugated with chitosan-capped GNPs, compared to free ampicillin [9].…”

Synthesis of Chitosan-Based Gold Nanoparticles: Antimicrobial and Wound-Healing Activities

“…Therefore, Chi/AuNPs may inhibit fungal growth by chelating various transitional metal ions, inhibiting enzymes. AuNPs based on chitosan have been widely used for the inhibition of bacterial growth and biofilm [ 80 , 81 , 82 ]. Additionally, a succinyl–chitosan gold nanocomposite was used to inhibit the growth of C. albicans [ 83 ].…”

Roles of chitosan in synthesis, antibacterial and anti-biofilm properties of bionano silver and gold

“…24,25 The shi to 534 nm was due to a local change in the refractive index caused by CS coating. 26 Particle size, PDI and zeta potential…”