Changes in fibrinogen adsorbed to segmented polyurethanes and hydroxyethylmethacrylate-ethylmethacrylate copolymers

Area of Science:

• Biomaterials Science
• Surface Chemistry
• Hematology

Background:

• Fibrinogen adsorption influences platelet adhesion and thrombus formation.
• The Vroman effect describes a time- and concentration-dependent maximum in fibrinogen adsorption.
• Understanding fibrinogen-surface interactions is crucial for biomaterial development.

Purpose of the Study:

• To investigate the impact of surface chemistry on the Vroman effect for fibrinogen adsorption.
• To examine the influence of polymer properties on fibrinogen adsorption kinetics and binding strength.
• To assess the transition of adsorbed fibrinogen states on different material surfaces.

Main Methods:

• Studied fibrinogen adsorption to HEMA/EMA copolymers, Biomer, and segmented polyurethanes (PEUs).
• Varied plasma concentration and adsorption time to observe the Vroman effect.
• Assessed the displacement of adsorbed fibrinogen by blood plasma over time.

Main Results:

• All materials showed maximal fibrinogen adsorption at intermediate plasma concentrations.
• Hydrophobic polymers demonstrated greater retention of adsorbed fibrinogen.
• Fibrinogen adsorbed for shorter durations (1 min) was more readily displaced than that adsorbed for longer durations (1 h).

Conclusions:

• Surface chemistry significantly influences fibrinogen adsorption dynamics and the Vroman effect.
• Adsorbed fibrinogen undergoes a transition to a more tightly bound state over time.
• Hydrophobicity of the polymer surface correlates with increased fibrinogen retention.