Construction and hemocompatibility study of highly bioactive heparin-functionalized surface

Area of Science:

• Biomaterials Science
• Surface Chemistry
• Medical Device Coatings

Background:

• Developing hemocompatible materials is crucial for medical devices.
• Heparin immobilization is a common strategy to impart anticoagulant properties.
• Existing methods for heparin surface functionalization can face challenges with stability and bioactivity retention.

Purpose of the Study:

• To develop a simple and effective method for creating stable anticoagulant surfaces.
• To investigate the heparin-binding affinity and retention of plasma-polymerized allylamine (PPAam) films.
• To evaluate the hemocompatibility of heparin-functionalized PPAam (Hep-PPAam) surfaces.

Main Methods:

• Passive adsorption of heparin onto protonated plasma-polymerized allylamine (PPAam) films.
• Characterization of heparin retention after long-term immersion in phosphate-buffered saline (PBS).
• Assessment of anticoagulant activity using activated partial thromboplastin time (aPTT) assays.
• Evaluation of blood-material interactions, including platelet and fibrinogen adhesion and activation.

Main Results:

• Protonated PPAam surfaces exhibit high affinity for heparin adsorption.
• Hep-PPAam surfaces demonstrate excellent heparin retention upon prolonged PBS immersion.
• Hep-PPAam surfaces significantly prolonged aPTT compared to 316L stainless steel.
• Reduced blood platelet adhesion and activation, along with inhibited fibrinogen adsorption and activation, were observed.

Conclusions:

• A simple, passive adsorption method effectively creates stable, bioactive heparinized surfaces.
• The Hep-PPAam surface modification significantly enhances hemocompatibility.
• This approach offers a promising strategy for improving the performance of blood-contacting medical devices.