Silver nanoparticles synthesized and coated with pectin: An ideal compromise for anti-bacterial and anti-biofilm action combined with wound-healing properties

Abstract

The synthesis of Ag nanoparticles from Ag has been investigated, with pectin acting both as reductant and coating.∼100% Ag to Ag(0) one-pot conversion was obtained, yielding p-AgNP, i.e. an aqueous solution of pectin-coated spherical Ag nanoparticles (d=8.0±2.6nm), with a<1ppm concentration of free Ag cation. Despite the low free Ag concentration and low Ag release with time, the nature of the coating allows p-AgNP to exert excellent antibacterial and antibiofilm actions, comparable to those of ionic silver, tested on E. coli (Gram-) and S. epidermidis (Gram+) both on planctonic cells and on pre- and post-biofilm formation conditions. Moreover, p-AgNP were tested on fibroblasts: not only p-AgNP were found to be cytocompatible but also revealed capable of promoting fibroblasts proliferation and to be effective for wound healing on model cultures. The antibacterial activity and the wound healing ability of silver nanoparticles are two apparently irreconcilable properties, as the former usually requires a high sustained Ag release while the latter requires low Ag concentration. p-AgNP represents an excellent compromise between opposite requirements, candidating as an efficient medication for repairing wounds and/or to treat vulnerable surgical site tissues, including the pre-treatment of implants as an effective prophylaxis in implant surgery.

Self‐Assembled Monolayers of Silver Nanoparticles: From Intrinsic to Switchable Inorganic Antibacterial Surfaces

“…Such AgNP revealed a fair antimicrobial effect as colloidal solutions, despite their low Ag + release, with a MICs for the GSH‐capped AgNP of 180 and 15 µg/mL for S. aureus and E. coli , respectively (MIC = minimum inhibitory concentration). This is mostly due to the disrupting and penetrating ability of such GSH‐coated AgNP towards E. coli and S. aureus , an effect observed also for pectin‐embedded AgNP and for biosynthesized AgNP (bearing the cell free protein of Rhizopus oryzae as coating), in the latter case displaying antibacterial action against E. coli (Gram‐) and Pseudomonas aeruginosa . The same citrate‐coated AgNP were grafted on glass|MPTS and further overcoated with GSH on their available surface, in a typical LbL approach .…”

Evaluation of keratin biomaterial containing silver nanoparticles as a potential wound dressing in full‐thickness skin wound model in diabetic mice

“…In the last few years, application of nanosilver has increased in healthcare, especially in wound management. Materials containing silver ions or nanoparticles have been applied as wound dressings to promote healing, infection prevention, and treatment (Konop, Damps, Misicka, & Rudnicka, 2016;Pallavicini et al, 2017).…”

Green synthesis of polysaccharide-based inorganic nanoparticles and biomedical aspects

“…8.5). Findings showed a significant wound healing process in contact with pectin-based AgNPs (8 nm), a decreasing trend was observed in width of the wound; 503 ± 5.98 μm at time zero, 424 ± 28.8 μm after 24 h, 239 ± 17.5 μm after 48 h, and completely closed wound gap after 72 h [108]. A study on excision and incision wound models in vivo also exhibited that mannan sulfate polysaccharide-based AgNPs (MS-AgNPs) (spherical shape, 20 nm) can be effectively used in wound healing process.…”