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.

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A cheap and easily obtainable wheat gluten (WG) was used to fabricate bio-foams via a simple method of stirring, heating, and lyophilization. The foam possesses a 3D layered porous structure with interconnected channels, and the biofoam has excellent mechanical properties through glycerol plasticization and glutaraldehyde (GA) cross-linking. The water absorption and volume expansion rate can reach 793.67 ∼ 918.45% and 201.47 ∼ 239.53% respectively. In dry state, the foams had good compression resilience, and can basically recover its original shape after withstanding 60% compression strain for about 7 h. In wet state, they can withstand 10 cycles of compression test, and had good compressive resilience and durability; they also had fast liquid-triggered shape recovery performance, of which the foams can reabsorb liquid, expand, and recover its original shape within 40 seconds after withstanding 80% compression strain. In addition, The hemolysis rates of red blood cells treated with 1, 3, and 5 mg/mL of 14WG-20g-5GA foam suspension were 0.53 ± 0.12%, 2.12 ± 0.34%, and 3.97 ± 0.21%, respectively, all of which were below the permissible range for biological materials (<5%). The above-mentioned advantages made the sustainable foams be potentially useful for medical dressings, especially for the treatment of non-compressible haemorrhaging, which offered a new field of application for WG protein and its added value was also increased obviously.