Selenium-containing polyurethane with elevated catalytic stability for sustained nitric oxide release.

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Medical Device Engineering

Background:

• Achieving stable, physiological nitric oxide (NO) release from biomedical materials is crucial for NO-based therapies but remains challenging.
• Existing NO-generating polymers often lose catalytic activity over time due to unstable catalytic sites, limiting long-term applications.
• The development of robust NO-releasing materials with sustained catalytic function is essential for advancing medical device technology.

Purpose of the Study:

• To design and synthesize a novel NO-generating polymer with enhanced catalytic stability for long-term NO release.
• To investigate the impact of incorporating catalytic sites into the polymer backbone on NO release kinetics and material properties.
• To evaluate the biocompatibility and hemocompatibility of the developed materials for potential use in blood-contacting medical devices.

Main Methods:

• Synthesis of selenium-containing polyurethane (PU-Se) using 2,2'-diselenodiethanol (SeDO) as a chain extender.
• Preparation of PU/PU-Se blend films with varying PU-Se content to study catalytic performance.
• Assessment of NO release rates, catalytic stability (up to 30 days in PBS), platelet adhesion, hemolysis, and mechanical properties.

Main Results:

• The PU/PU-Se blend films demonstrated excellent catalytic activity and superior catalytic stability compared to surface-coated materials.
• PU-Se-10 blend film achieved a stable nitric oxide release rate of 5.05 × 10^-10 mol cm^-2 min^-1 after 30 days of PBS exposure.
• The developed PU/PU-Se films showed reduced platelet activation and adhesion, a low hemolysis ratio, excellent biocompatibility, and comparable mechanical properties to pure PU.

Conclusions:

• Incorporating catalytic sites into the polymer backbone via PU-Se synthesis offers a promising strategy for achieving stable, long-term nitric oxide release.
• The novel PU/PU-Se materials exhibit excellent hemocompatibility and biocompatibility, making them suitable for blood-contacting medical devices.
• These findings highlight the potential of the newly designed PU-Se for advanced NO-based therapies requiring sustained physiological NO levels.