Polyurethane/polyurethane nanoparticle-modified expanded poly(tetrafluoroethylene) vascular patches promote...

Area of Science:

• Biomaterials Science
• Vascular Tissue Engineering
• Nanotechnology in Medicine

Background:

• Expanded polytetrafluoroethylene (ePTFE) is a common vascular graft material but suffers from poor performance in small-diameter applications due to thrombosis and calcification.
• There is a critical need to enhance the biocompatibility and endothelialization of ePTFE grafts to improve surgical outcomes.
• Nanoparticle modification offers a promising strategy to improve the surface properties and biological performance of biomaterials.

Purpose of the Study:

• To develop and evaluate a novel polyurethane/polyurethane nanoparticles/ePTFE composite vascular patch (PPVP) for improved vascular grafting.
• To assess the blood compatibility, cell compatibility, and in vivo performance of the modified ePTFE graft.
• To investigate the potential of PPVP as an alternative to current small-diameter vascular grafts.

Main Methods:

• A polyurethane/polyurethane nanoparticles (PU/PU-NPs) composite film was prepared using a cosedimentation method.
• A PU/PU-NPs/ePTFE vascular patch (PPVP) was constructed by coating the composite onto an ePTFE graft surface.
• In vitro assessments of blood and cell compatibility, platelet adhesion, cell attachment, and proliferation were performed. In vivo implantation in abdominal arteries was conducted to evaluate graft patency and endothelialization.

Main Results:

• The PU/PU-NPs composite film exhibited significantly improved blood and cell compatibility compared to pure PU.
• The PPVP demonstrated a nanopatterned surface, enhanced blood and cell compatibility, inhibited platelet adhesion, and promoted cell attachment and proliferation.
• In vivo implantation showed that the PPVP graft remained patent and achieved endothelialization within 30 days.

Conclusions:

• The PU/PU-NPs modification effectively improved the surface properties and biological performance of ePTFE vascular grafts.
• The PPVP exhibits excellent biocompatibility and promotes rapid endothelialization, addressing key limitations of current ePTFE grafts.
• PPVP represents a promising alternative for small-diameter vascular bypass surgeries, potentially reducing graft failure rates.