Hemocompatibility of pseudozwitterionic polymer brushes with a systematic well-defined charge-bias control

Area of Science:

• Biomaterials Science
• Surface Chemistry
• Polymer Science

Background:

• Developing hemocompatible materials is critical for biomedical applications involving blood contact.
• Pseudozwitterionic surfaces offer a promising alternative to traditional zwitterionic materials.
• Controlling surface charge distribution is key to achieving desired hemocompatibility.

Purpose of the Study:

• To develop and characterize a pseudozwitterionic surface with tunable mixed positive and negative charges.
• To investigate the hemocompatibility of this novel surface for biomedical applications.
• To establish the relationship between surface charge bias and blood compatibility.

Main Methods:

• Surface-initiated atom transfer radical polymerization (ATRP) was used to graft poly(TMA-co-SA) copolymers.
• The ratio of [2-(methacryloyloxy)ethyl] trimethylammonium (TMA) and 3-sulfopropyl methacrylate (SA) monomers controlled surface charge composition.
• Hemocompatibility was assessed via protein adsorption assays (ELISA) and blood compatibility tests (platelet adhesion, plasma clotting, hemolysis).

Main Results:

• Hemocompatibility, including protein resistance and anti-blood cell adhesion, was precisely controlled by tuning the TMA/SA monomer ratio.
• Variations in charge bias influenced electrostatic interactions, leading to protein adsorption, blood cell adhesion, plasma clotting, and hemolysis.
• The poly(TMA-co-SA)-grafted surface demonstrated tunable hemocompatibility dependent on its charge bias level.

Conclusions:

• Pseudozwitterionic surfaces with controlled mixed charge distribution show significant potential for hemocompatible biomaterials.
• The charge bias of the poly(TMA-co-SA) surface is a critical factor determining its interaction with blood components.
• This approach offers a versatile strategy for designing advanced biomaterials for blood-contacting applications.