Electrospinning Device: The double-layer silk fibroin/sodium alginate scaffold promotes full-thickness wound vascularization and promotes the inflammatory phase

Background

The double-layer scaffold developed in this study simulates the layered structure of human skin. The upper membrane is prepared by casting and has epidermal function, while the lower membrane is prepared by freeze-drying and simulates the extracellular matrix (ECM) structure. This design enhances the tension of fibrin and sodium alginate, provides good mechanical properties and moderate hydrophilicity.

Mechanical properties and barrier function

The non-porous, flat and waterproof surface of the upper membrane ensures protection ability, reduces the risk of sepsis, and allows cleaning and disinfection around the wound. The uniform porous structure of the lower scaffold is suitable for effective nutrient supply and fluid diffusion, and allows cell attachment and ingrowth, while having a non-porous structure, good mechanical properties, moderate hydrophilicity and suitable water vapor permeability.

Biocompatibility and degradability

The double-layer scaffold shows good biocompatibility, fibroblast proliferation and stimulation of collagen deposition. SF protein stimulates cell migration and proliferation by activating multiple signaling pathways, indicating that its biological properties are mainly attributed to SF protein. In addition, the double-layer scaffold lost about 60% of its weight in collagenase IA solution while maintaining its intact structure both in vitro and in vivo, indicating that it has a suitable degradation rate.

Evaluation of in vitro and in vivo biological properties

In vitro experiments showed that the wound surface covered by the double-layer scaffold created a suitable moist wound healing environment and significantly promoted wound healing. In particular, on the 14th day, the granulation tissue of the wound surface treated with the double-layer scaffold became thicker and re-epithelialization was more complete. In vivo experiments further confirmed that the double-layer scaffold promoted wound healing, granulation tissue formation, re-epithelialization and transition of skin components to normal skin by providing a moist wound environment, advancing the inflammatory stage and stimulating angiogenesis.

Wound healing effect

The full-thickness wound healing test in rabbits in vivo showed that the double-layer scaffold promoted full-thickness wound healing and regeneration through a single local administration, mainly by providing a moist wound environment, promoting vascularization and advancing the inflammatory stage.

Connection with electrospinning

Electrospinning technology was used to prepare electrospun medical sutures for wound healing, indicating its potential for application in wound care and healing. The bilayer scaffold was also designed to provide a moist wound environment, promote vascularization and advance the inflammatory stage, thereby accelerating wound healing and regeneration.

Conclusion

As a ready-made, cell-free wound dressing, the bilayer scaffold (PM@SASFm) exhibited enhanced mechanical properties, potential to prevent wound dehydration and microbial contamination, suitable biodegradation, good biocompatibility, and stimulated cell proliferation and collagen deposition. Therefore, the bilayer scaffold is a promising full-thickness wound regeneration dressing, and its optimization method may be an inspiration for other viable wound dressings.

Electrospinning Nanofibers Article Source:

http://10.1088/1758-5090/ac73b7