Polyurethane coatings release bioactive antibodies to reduce bacterial adhesion

Area of Science:

• Biomaterials Science
• Immunology
• Polymer Chemistry

Background:

• Biomaterial surface coatings are crucial for preventing device-associated infections.
• Polyurethane hydrogels offer biocompatibility but require enhanced antimicrobial properties.
• Antibody immobilization can provide targeted antimicrobial activity.

Purpose of the Study:

• To formulate a biomedical grade polyurethane hydrogel coating with dispersed bioactive antibodies.
• To evaluate the coating's ability to reduce bacterial adhesion and promote bacterial clearance.
• To assess the bioactivity and controlled release of antibodies from the hydrogel matrix.

Main Methods:

• Formulation of a polyurethane prepolymer dispersion with solid human immunoglobulin G (IgG) in isopropanol.
• Coating of polymer substrates via simple immersion and solvent casting.
• In vitro antimicrobial studies using Escherichia coli.
• Opsonophagocytic assays with human neutrophils to assess antibody bioactivity.

Main Results:

• Antibody release up to approximately 50 microg/cm(2) from a 15% w/w IgG coating.
• Significant reduction in bacterial adhesion (p<0.05) on antibody-coated surfaces compared to bare surfaces.
• Greatest bacterial adhesion reduction observed with the antibody-releasing hydrogel coating.
• Maintained antibody bioactivity, significantly enhancing bacterial killing in vitro.

Conclusions:

• A controlled-release polyurethane hydrogel coating effectively imparts infection resistance to biomaterials.
• The coating combines low surface adhesion properties with the immune-clearing capacity of antibodies.
• This approach reduces bacterial adhesion and promotes clearance via natural immune mechanisms, offering a novel strategy for infection prevention.