Novel Light-Responsive Hydrogels with Antimicrobial and Antifouling Capabilities

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Surface Chemistry

Background:

• Medical device infections are a significant concern.
• Current antimicrobial materials require lengthy activation times.
• Smart materials offer dynamic control over surface properties.

Purpose of the Study:

• To develop a photoresponsive hydrogel with tunable antimicrobial and antifouling properties.
• To investigate the UV-induced surface charge switching mechanism.
• To evaluate the material's efficacy in preventing bacterial adhesion and facilitating cell detachment.

Main Methods:

• Synthesis of poly[2-((4,5-dimethoxy-2-nitrobenzyl)oxy)- N-(2-(methacryloyloxy)ethyl)- N, N-dimethyl-2-oxoethan-1-aminium] (polyCBNA) hydrogel.
• UV irradiation at 365 nm to induce photolysis of 4,5-dimethoxy-2-nitrobenzyl groups.
• Assessment of protein adsorption/desorption dynamics.
• Evaluation of antibacterial activity and bacterial release.
• Testing of endothelial cell adhesion and detachment.

Main Results:

• PolyCBNA hydrogel demonstrated effective bacterial killing in its cationic state.
• UV irradiation rapidly switched the surface from cationic to zwitterionic, reducing protein adsorption and releasing attached bacteria.
• Light-triggered, nonenzymatic detachment of adhered endothelial cells was achieved.
• The material exhibited both antimicrobial and antifouling capabilities.

Conclusions:

• The developed photoresponsive polyCBNA polymer offers a smart solution for combating medical device-associated infections.
• Its rapid, light-induced transition from antimicrobial to antifouling properties is advantageous.
• Potential applications include self-sterilizing coatings, cell harvesting, and cell patterning.