Injectable tissue adhesive composite hydrogel with fibroblasts for treating skin defects

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Regenerative Medicine

Background:

• Developing advanced wound dressings is crucial for effective tissue repair.
• Injectable hydrogels offer advantages for wound site application and filling defects.
• Glycol chitosan (GC) possesses inherent tissue adhesion properties that can be leveraged for wound healing.

Purpose of the Study:

• To synthesize an injectable composite hydrogel using glycol chitosan (GC) and silica nanoparticles (SiNP).
• To evaluate the hydrogel's properties, including gelation, rheology, and tissue adhesion.
• To assess the hydrogel's efficacy in treating full-thickness skin defects in a mouse model.

Main Methods:

• Hydrogel synthesis via non-chemical crosslinking of GC with SiNPs.
• Rheological analysis to study sol-gel transition and mechanical properties.
• In vitro and in vivo studies using mouse skin adhesion tests and full-thickness skin defect models.

Main Results:

• The GC/SiNP hydrogel exhibited tunable gelation and mechanical properties influenced by component ratios and nanoparticle characteristics.
• The hydrogel demonstrated significant tissue adhesion, with a lap-shear stretching force of approximately 90 kPa.
• In vivo studies showed the hydrogel promoted hair follicle and microvessel growth, reducing scar formation in skin defects.

Conclusions:

• The injectable GC/SiNP composite hydrogel is a promising wound dressing material.
• Its inherent tissue adhesion and injectability facilitate application and wound coverage.
• The hydrogel supports cellular activity and promotes effective skin regeneration, minimizing scarring.