Antimicrobial PVA Hydrogels with Tunable Mechanical Properties and Antimicrobial Release Profiles

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Wound Healing Research

Background:

• Hydrogels are widely used in wound healing due to their biocompatibility and mechanical properties.
• Infections, particularly from drug-resistant bacteria, significantly impede wound healing, necessitating novel antimicrobial strategies.
• Crohn's disease-related fistulas present complex wound healing challenges requiring advanced therapeutic approaches.

Purpose of the Study:

• To design and develop a water-responsive shape memory polymer (SMP) hydrogel.
• To incorporate natural antimicrobials, specifically phenolic acids (PAs), for localized infection control.
• To evaluate the impact of PA incorporation on hydrogel properties for wound filling and healing applications.

Main Methods:

• Synthesized urethane-crosslinked poly(vinyl alcohol) hydrogels with chemically or physically incorporated cinnamic acid, p-coumaric acid, and caffeic acid.
• Assessed antimicrobial activity, biofilm formation, mechanical properties (modulus, elongation at break), shape memory behavior, and cell viability.
• Investigated the influence of PA type, concentration, and incorporation method on material performance.

Main Results:

• Physically incorporated PAs significantly enhanced antibacterial properties and reduced biofilm formation on hydrogel surfaces.
• Both modulus and elongation at break were simultaneously improved by PA incorporation.
• Cellular viability and growth were dependent on PA structure and concentration, with shape memory properties remaining unaffected.
• PA incorporation offered a method to tune material properties independently of the hydrogel's core chemistry.

Conclusions:

• Phenolic acid-containing hydrogels demonstrate potent antimicrobial properties and improved mechanical characteristics.
• These novel hydrogels show promise for wound filling, infection management, and promoting healing, especially in challenging cases like Crohn's fistulas.
• The ability to tune material properties via PA content and structure opens new avenues for advanced biomedical material design.