An asymmetric wettable chitosan–silk fibroin composite dressing with fixed silver nanoparticles for infected wound repair: in vitro and in vivo evaluation

Abstract

The treatment of large-area infected wounds remains a significant challenge, as there is no effective wound dressing for infected wound healing applicable to clinical applications. In this study, chitosan-silk fibroin composite scaffolds containing silver nanoparticles (AgNP) that underwent asymmetric modification were fabricated for tissue engineering dressings. The scaffolds were prepared from a solution containing a chitosan-silk-fibroin emulsion with added AgNPs using a lyophilization approach and with an asymmetric coating on the surface of one side. Transmission electron microscopy images and laser particle size analysis showed the AgNP distribution, scanning electron microscopy images showed the surface morphology of the dressings, and inductively coupled plasma mass spectrometry showed the silver content. The asymmetric wettability of the dressings was measured using a contact angle meter.High porosity, good moisture retention capability and appropriate tensile strength were observed by measuring the physical and mechanical properties. Good antimicrobial properties towards various bacteria were observed via in vitro antibacterial effect analysis. Controlled AgNP release by the dressings and their resistance to the infiltration of microorganisms were also observed in our experiments. A highly biocompatible dressing was observed by the MTT assay experiment and subcutaneous sensitization test.Moreover, the effects of the dressings on infected wound healing were measured in mice infected wound models. Analysis of the wound healing rate, bacterial cultures of the exudate, blood samples and histological examination all provided satisfactory results. These results demonstrate that the dressings we prepared offer the potential for infected wound tissue repair and regeneration.

Photothermal Responsive Porous Membrane for Treatment of Infected Wound

“…The water retention time of the CS/PVA and CS/PVA/Pd membrane is about 20 h (Figure 6c), which is higher than some previously reported dressing [32,33]. Effective dressing moisture retention helps to reduce clinical infections and scarring [34].…”

Chitosan/Silk Fibroin Materials for Biomedical Applications—A Review

“…Such a composite can be considered as wound dressing and tendon reconstruction material in future. Chitosan-silk fibroin composite scaffolds containing silver nanoparticles (AgNPs) were fabricated for tissue engineering dressings by Liu et al [ 179 ]. The materials fabricated in such a way showed good antimicrobial properties and can thus be considered for application in wound dressing.…”

Multifunctional electrospun asymmetric wettable membrane containing black phosphorus/Rg1 for enhancing infected wound healing

“…Asymmetric membrane was an emerging functional dressing since they can mimic construction of skin and furnish the compatible environment for wound healing 10 . Asymmetric membranes have a compact outer layer which similar to skin epidermis, exhibit hydrophobicity that could inhibit the adhesion of the bacteria and prevent the loss of water 1 . Moreover, the hydrophilic inner layer played the role of skin dermis, which could provide an ideal microenvironment of wound healing, and further promote delivery of nutrition and remove the excess exudates 11 .…”

“…Bacterial infection of a skin wound was the main reason of delayed wound healing, and high bacterial levels will hinder the progression of wound healing. 1 Unfortunately, prior study reported that infection caused by antimicrobial-resistant pathogens may lead to 10 million annual deaths by the year 2050. 2 Bacterial infection was usually accompanied by inflammation.…”

“…10 Asymmetric membranes have a compact outer layer which similar to skin epidermis, exhibit hydrophobicity that could inhibit the adhesion of the bacteria and prevent the loss of water. 1 Moreover, the hydrophilic inner layer played the role of skin dermis, which could provide an ideal microenvironment of wound healing, and further promote delivery of nutrition and remove the excess exudates. 11 Owing to their extraordinary properties containing water retention, high mechanical properties, and biocompatibility, asymmetric membranes have been applied in the biomedical field such as wound healing 12 and sensor.…”