Antibacterial thyme oil-loaded zwitterionic emulsion hydrogels

Area of Science:

• Materials Science
• Biomaterials Engineering
• Polymer Chemistry

Background:

• Emulsion hydrogels combine properties of emulsions and hydrogels, enabling co-delivery of hydrophobic and hydrophilic substances.
• Cellulose acetoacetate (CAA) acts as both an emulsifier and polymerization mediator.
• Zwitterionic polymers offer hydration and anti-fouling properties.

Purpose of the Study:

• To construct thyme oil-loaded zwitterionic emulsion hydrogels.
• To investigate the potential of enzyme-mediated polymerization for encapsulating hydrophobic bioactive ingredients.
• To evaluate the properties and bioactivity of the developed emulsion hydrogels.

Main Methods:

• Ternary enzyme-mediated polymerization initiated by cellulose acetoacetate-horseradish peroxidase-hydrogen peroxide (CAA-HRP-H2O2).
• Formation of thyme oil-in-water (O/W) emulsions stabilized by CAA.
• Polymerization of zwitterionic monomers (poly(sulfobetaine methacrylate) - PSBMA) within the emulsion template.

Main Results:

• Successfully constructed thyme oil-loaded zwitterionic emulsion hydrogels with interconnected, uniform, and adjustable porous structures.
• Achieved tunable mechanical properties and good hydration capacity.
• Demonstrated excellent antifouling performance, good biocompatibility, and significant antibacterial activity against S. aureus and E. coli.

Conclusions:

• Ternary enzyme-mediated polymerization in O/W emulsion templates is an efficient strategy for encapsulating hydrophobic bioactive ingredients.
• The developed emulsion hydrogels show promise for drug delivery and biomedical applications.
• CAA plays a crucial dual role as emulsifier and polymerization mediator.