Antimicrobial activity of catechol functionalized-chitosan versus Staphylococcus epidermidis

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Wound Healing

Background:

• Mussel-inspired adhesive polymers with catechol groups offer potential for wound healing due to muco-adhesive properties.
• Effective wound dressings require a combination of muco-adhesiveness and antimicrobial activity.
• Chitosan is a biocompatible polymer with inherent antimicrobial properties.

Purpose of the Study:

• To synthesize catechol-functionalized chitosan (CS-HCAF) by reacting chitosan with hydrocaffeic acid (HCAF).
• To investigate the impact of varying catechol content on the intrinsic antimicrobial activity of chitosan.
• To evaluate the muco-adhesive and antioxidant properties of the synthesized CS-HCAF derivatives for wound dressing applications.

Main Methods:

• Catechol functionalization of chitosan using hydrocaffeic acid.
• Antimicrobial activity assessment using minimum inhibitory concentration (MIC) against Staphylococcus epidermidis.
• Evaluation of bacterial adhesion reduction on coated wound dressings.
• Antioxidant property determination using EC50 values.

Main Results:

• Catechol functionalization unexpectedly enhanced chitosan's antimicrobial activity, reducing MIC against Staphylococcus epidermidis fourfold.
• A wound dressing coated with CS-HCAF demonstrated a significant 3-log reduction in Staphylococcus epidermidis adhesion.
• CS-HCAF derivatives exhibited notable antioxidant properties, with EC50 values ranging from 20 to 60 μg/mL.

Conclusions:

• Catechol-functionalized chitosan (CS-HCAF) exhibits enhanced antimicrobial and muco-adhesive properties, making it a promising candidate for wound dressings.
• The combined antimicrobial, muco-adhesive, and antioxidant characteristics of CS-HCAF derivatives support their potential in advanced wound care.
• This study highlights the successful modification of chitosan to improve its efficacy as a wound healing material.