Silk fibroin/chitosan hydrogel with antibacterial, hemostatic and sustained drug‐release activities

Abstract

Hydrogels are viable wound dressing materials that have gained increasing attention due to their specific physicochemical properties, biocompatibility and environmental responsiveness. In addition to keeping a wound area moist, hydrogels characterized by a porous network structure and regulated drug-release capacity promote the various phases of wound healing by effectively loading a drug and inducing anti-infection activity. In this study, we prepared a multifunctional hydrogel with antibacterial, hemostatic and sustained drug-release activities by chemically crosslinking silk fibroin (SF) and chitosan (CS) biomacromolecules. Results of characterization revealed that the synthesized hydrogel presents higher swelling and in vitro degradation rates under acidic conditions than in a neutral environment. Moreover, the three-dimensional network structure of the material and the transformation of the SF secondary structure resulted in enhanced compressive mechanical properties (maximum compressive stress of 50-130 kPa). In vitro studies of drug loading and release, antibacterial assay, cytotoxicity studies, and coagulation assay were performed. Results showed that the prepared hydrogel exhibits good bacteriostatic and hemostatic properties, and it is not toxic towards human skin fibroblasts. Therefore, the designed SF/CS hydrogel constitutes an excellent candidate material for wound dressings.

Gallium ions incorporated silk fibroin hydrogel with antibacterial efficacy for promoting healing of Pseudomonas aeruginosa-infected wound

“…A high proportion of the SF is bound to increase the viscosity of the hydrogel solution, inducing a short gelation time which can restrict the crosslinking and at the same time affect the porosity ( Xu et al, 2021 ). The SEM evaluation of the influence of Ga (NO 3 ) 3 on the micromorphological structure of the hydrogel after dried freezing revealed a lamellar interconnected pores size for SF hydrogel, Figure 3A , and a smaller but increased pore size for Ga (NO 3 ) 3 crosslinked hydrogel SF/Ga, Figure 3B .…”

“…Some reports indicate that the β-sheet is directly responsible for a silk hydrogel mechanical property as a result of improved crosslinks ( Hu et al, 2010 ; Guziewicz et al, 2011 ; Xu et al, 2021 ). Hence crosslinking coordinates and improves the mechanical performance of a hydrogel further enabling resistance to easy deformation ( Rammensee et al, 2006 ; Zawko et al, 2009 ; Jeon et al, 2014 ).…”

Preparation and Characterization of Natural Silk Fibroin Hydrogel for Protein Drug Delivery

“…The cytotoxicity of the silk fibroin hydrogels was evaluated by measuring the survival rate of human hepatoma cells (HepG2 cells) after co-culture in a silk fibroin hydrogel leaching solution for a period of time by an MTT assay. Under sterile conditions, we retrieved the 96-well plate in which the cells were grown adherently and added 100 μL of silk fibroin hydrogel sample leaching solution and 100 μL of fresh DMEM medium containing 10% fetal bovine serum and 1% double antibody (100 U/mL penicillin and 100 μg/mL streptomycin) to each well and cultured the plate in a cell incubator at 37 °C with 5% CO 2 [ 43 ]. After 48 h of incubation in the incubator, we added 20 μL of MTT solution (1 mg/mL) to each well.…”

Chitosan/Silk Fibroin Materials for Biomedical Applications—A Review

“…Apart from the tests of mixtures of chitosan with silk fibroin in the form of diluted solutions, nanofibers [ 112 , 117 , 118 , 119 ], three-dimensional structures [ 101 , 108 , 109 , 120 , 121 , 122 , 123 , 124 , 125 , 126 , 127 , 128 , 129 ], films [ 103 , 105 , 110 , 114 , 130 , 131 , 132 , 133 ], microparticles [ 134 , 135 , 136 , 137 ], and hydrogels [ 138 , 139 , 140 ] were also obtained and characterized ( Figure 5 ).…”

“…CTS/SF hydrogels cross-linked with EDC/NHS, prepared as a prospective material for sustained drug release, had porous structure, stable mechanical strength, stimuli responsive swelling performance, and drug release behaviors [ 139 ]. However, CTS/SF hydrogel constitutes an excellent candidate for wound dressings because it presents higher swelling and in vitro degradation rates under acidic conditions than in a neutral environment, exhibits good bacteriostatic and hemostatic properties, and is non-toxic towards human skin fibroblasts [ 140 ].…”