Fabrication and Characterization of an Antibacterial Chitosan/Silk Fibroin Electrospun Nanofiber Loaded with a Cationic Peptide for Wound-dressing Application

Abstract

Wound infections are still problematic in many cases and demand new alternatives for current treatment strategies. In recent years, biomaterials-based wound dressings have received much attention due to their potentials and many studies have been performed based on them. Accordingly, in this study, we fabricated and optimized an antibacterial chitosan/silk fibroin (CS/SF) electrospun nanofiber bilayer containing different concentrations of a cationic antimicrobial peptide (AMP) for wound dressing applications. The fabricated CS/SF nanofiber was fully characterized and compared to the electrospun silk fibroin and electrospun chitosan alone in vitro. Then, the release rate of different concentrations of peptide (16, 32, and 64 µg/ml) from peptide-loaded CS/SF nanofiber was investigated. Finally, based on cytotoxic activity, the antibacterial activity of scaffolds containing 16 and 32 µg/ml of peptide was evaluated against standard and multi-drug resistant strains of Staphylococcus aureus and Escherichia coli isolated from burn patients. The peptide-loaded CS/SF nanofiber displayed appropriate mechanical properties, high water uptake, suitable biodegradation rate, a controlled release without cytotoxicity on Hu02 human foreskin fibroblast cells at the 16 and 32 µg/ml concentrations of peptide. The optimized CS/SF containing 32 µg/ml peptide showed strong antibacterial activity against all experimental strains from standard to resistant. The results showed that the fabricated antimicrobial nanofiber has the potential to be applied as a wound dressing for infected wound healing, although further studies are needed in vivo.

Fabrication of an Antimicrobial Peptide-Loaded Silk Fibroin/Gelatin Bilayer Sponge to Apply as a Wound Dressing; An In Vitro Study

“…Our results showed that this scaffold, in addition to having antimicrobial properties, facilitates the proliferation of fibroblasts and increases cell and cell adhesion. It also indicated suitable mechanical attributes, high water uptake, appropriate biodegradation rate, and a controllable release (Khosravimelal et al 2021). In comparison with this study, the current sponge had a stunning antibacterial effect at a concentration of 16 µg/ml, which could be related to the mentioned properties of the sponge Scaffolds.…”

“…CM11, as a short cationic peptide derived from cecropin and melittin peptides, is comprised of 11 amino acid residues (WKLFKKILKVL-NH 2 ) that have been shown to have a broad-spectrum antibacterial activity against gram-negative and positive bacteria. Based on studies, AMPs such as CM11 peptide can be added to biomaterial wound dressings to improve their antiinfective properties (Moghaddam et al 2012, Amani et al 2015, Khosravimelal et al 2021). Accordingly, a potential antibacterial wound dressing of sponge SF/Gel scaffolds comprising various concentrations of CM11 peptide has been investigated.…”