A silver nanocomposite biomaterial for blood-contacting implants

Area of Science:

• Biomaterials Science
• Nanotechnology
• Cardiovascular Engineering

Background:

• Cardiovascular implants require materials resistant to infection and thrombosis.
• Polyhedral-oligomeric-silsesquioxane-poly(carbonate-urea)urethane (POSS-PCU) is a promising nanocomposite polymer.
• Silver nanoparticles (nanosilver, NS) possess antibacterial properties.

Purpose of the Study:

• To investigate the impact of nanosilver (NS) incorporation into POSS-PCU on its thrombogenicity.
• To evaluate the blood compatibility and antithrombogenic potential of POSS-PCU-NS nanocomposites.

Main Methods:

• POSS-PCU was combined with varying concentrations of NS (0.20% to 1.50%).
• Surface wettability, platelet adhesion (Alamar Blue assay), platelet activation (PF4 ELISA), whole blood coagulation kinetics (TEG), and hemolysis were assessed.
• Different POSS-PCU-NS concentrations were tested: POSS-PCU-NS16, POSS-PCU-NS32, POSS-PCU-NS64, and POSS-PCU-NS128.

Main Results:

• Increased NS levels enhanced surface hydrophilicity.
• Platelet adhesion and activation decreased in a concentration-dependent manner with increasing NS content.
• POSS-PCU-NS16 and POSS-PCU-NS32 showed retained or enhanced antithrombogenic properties and no hemolysis.
• Higher concentrations (POSS-PCU-NS64, POSS-PCU-NS128) reduced antithrombogenic effects and induced hemolysis.

Conclusions:

• POSS-PCU-NS32 exhibits potent antithrombogenic properties and excellent blood compatibility.
• This nanocomposite shows significant potential for developing safer cardiovascular implants.
• Optimized NS incorporation is crucial for balancing antibacterial and antithrombogenic functions.