Composite elastomeric polyurethane scaffolds incorporating small intestinal submucosa for soft tissue engineering.

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Polymer Chemistry

Background:

• Current soft tissue replacement methods have limitations like poor resilience, mechanical integrity, and donor site morbidity.
• Bio-absorbable scaffolds with high resilience are needed to stimulate natural tissue regeneration.
• Developing elastic composites of synthetic polymers and extracellular matrices in non-toxic aqueous solutions is challenging.

Purpose of the Study:

• To develop a novel approach for soft tissue engineering using chemically crosslinked tridimensional scaffolds.
• To create polyurethane (PU) and small intestinal submucosa (SIS) composite scaffolds.
• To evaluate the bioactivity, resilience, and tissue regeneration potential of these PU/SIS composites.

Main Methods:

• Synthesized water-based polyurethane (PU) from polytetramethylene ether glycol, isophorone diisocyanate, and 2,2-bis(hydroxymethyl) butyric acid.
• Incorporated PU into a bioactive extracellular matrix of small intestinal submucosa (SIS) to form PU/SIS composites.
• Characterized structural and mechanical properties, assessed cell attachment and proliferation using human umbilical vein endothelial cells, and performed subcutaneous implantation in animals.

Main Results:

• The synthesized PU/SIS samples exhibited high resilience and enhanced cell viability without cytotoxicity.
• Subcutaneous implantation showed sound implant integration and vascularization within the PU/SIS composites.
• The presence of SIS promoted cell infiltration, angiogenesis, and ultimately tissue regeneration.

Conclusions:

• The developed PU/SIS composite scaffolds possess high bioactivity and resilience.
• These novel scaffolds effectively support cell growth, vascularization, and tissue regeneration.
• The PU/SIS composites represent a promising biomaterial for soft tissue engineering applications.