Electrospinning Equipment: Polydopamine-coated tussah silk membrane promotes cell adhesion and wound healing in skin tissue repair

Advantages of silk-based materials

Silk-based materials, especially silk fibroin (SF) and another silk protein AF (obtained from wild silkworm Antheraca pernyi), have become ideal materials for wound dressings due to their excellent biocompatibility, biodegradability, mechanical properties, and ability to promote cell attachment, diffusion, and proliferation. AF contains a high proportion of arginine-glycine-aspartic acid (RGD) sequences, which can specifically bind to cell integrins, thereby enhancing cell adhesion. Therefore, AF is expected to become a promising wound dressing due to its enhanced cell adhesion ability.

Research progress of silk-based wound dressings

The research team of Yang Mingying of Zhejiang University used mussel polydopamine (PDA) to coat the surface of AF membrane and developed a new wound dressing (PAF). The PDA coating significantly improved the hydrophilicity and protein adsorption capacity of the AF membrane, further promoting the adhesion and migration of cells required for wound healing.

Material characterization: AFM results showed that PDA nanoparticles aggregated on the PAF membrane, resulting in a rougher surface than the AF membrane. The change in water contact angle showed that the PDA coating improved the hydrophilicity of the AF film. XPS results further confirmed that the coating was actually a layer of PDA nanoparticles, and its N/C molar ratio was close to the theoretical value of pure dopamine. Fluorescently labeled bovine serum albumin (FITC-BSA) detection showed that the PDA nanoparticle coating promoted the adsorption of BSA and enhanced the adhesion ability of cells.

Cell behavior study: Experiments using rat mesenchymal stem cells (rMSCs) showed that PDA nanoparticles promoted the adhesion, spreading and proliferation of rMSCs. The wound healing rate of PAF film was significantly faster than that of AF film, especially PAF2 film showed the highest healing ability.

In vivo healing effect: In the full-thickness wound model constructed on the back of rats, PAF film accelerated wound healing than AF film. Histological observations showed that the new skin tissue treated with PAF film was closer to normal skin in structure, with better biocompatibility and the ability to promote skin regeneration.

Application of electrospinning equipment

Electrospinning equipment plays an important role in the preparation of silk-based materials and can produce high-performance nanofibers. These nanofibers can be used to construct wound dressings, with the following advantages:

Preparation of nanofiber structures: Electrospinning can produce uniform continuous fibers with diameters ranging from nanometers to micrometers. These fibers can be used as tissue engineering scaffolds to simulate the microstructure of natural extracellular matrix and promote cell migration, proliferation and differentiation.

Regulation of fiber morphology and arrangement: By adjusting the parameters in the electrospinning process (such as spinning solution concentration, viscosity, electric field strength, etc.), the diameter and morphology of the fibers can be precisely controlled to optimize the performance of the material.

Loading bioactive substances: Electrospinning equipment can prepare nanofiber scaffolds loaded with bioactive molecules. By controlling the release rate, the continuous action of bioactive substances at the wound site can be achieved, further improving the biocompatibility of the dressing and the effect of promoting wound healing.

Summary and Outlook

The application of silk-based materials in wound dressings shows great potential, especially through functional surface coatings and composites with other materials, the performance of silk-based dressings has been significantly improved. Electrospinning equipment plays an important role in the preparation of silk-based materials, and can prepare nanofibers with excellent structure and performance to promote cell growth and tissue regeneration. Future research can further explore the combination of silk-based materials with other bioactive substances, as well as their application effects in different types of wound healing, to promote the clinical transformation and application of silk-based wound dressings.

Electrospinning Nanofibers Article Source:

https://doi.org/10.1021/acsami.9b12643