Heparinized Polyurethane Surface Via a One-Step Photografting Method

Area of Science:

• Biomaterials Science
• Surface Chemistry
• Polymer Science

Background:

• Traditional heparin grafting methods onto polyurethane (PU) suffer from low efficiency.
• Coupling chemistry methods present limitations for effective surface modification.

Purpose of the Study:

• To develop a rapid, one-step photografting technique for immobilizing heparin derivatives onto PU surfaces.
• To investigate the impact of varying anchor point densities on heparinized PU properties.

Main Methods:

• Synthesis of three heparin derivatives with different aryl azide group percentages.
• Immobilization of heparin derivatives onto PU surfaces via photografting.
• Characterization of surface properties, including charge, antithrombin III binding, and blood coagulation times.

Main Results:

• Heparinized PU with the lowest anchor point density exhibited the highest negative surface charge and antithrombin III binding.
• Reduced anchor point density significantly inhibited platelet adhesion and prolonged various blood coagulation times.
• Immobilized heparin bioactivity increased from 22.9% to 36.9% with decreased anchor density.

Conclusions:

• The one-step photografting method offers an efficient alternative for heparin immobilization.
• Lowering anchor point density enhances heparin's anticoagulant properties and bioactivity through increased molecular mobility and surface charge.
• This approach holds promise for developing improved blood-contacting medical devices.