Fabrication of Antibacterial and Flexible Hydrogels Based on Citric Acid Containing Tannic Acid for Wound Dressing

ABSTRACT In this research, a biomonomer based on hydroxyethyl methacrylate, citric acid, and polyethylene glycol (HEMA‐CA‐PEG) was synthesized. After confirming the reaction through 1 H‐NMR and FT‐IR tests and obtaining the intended monomer, a flexible hydrogel was synthesized as a wound dressing, and its mechanical properties were evaluated using tensile strength, DMTA, and rheometry tests. This synthesized hydrogel exhibited sufficient mechanical properties. To enhance the efficiency of this hydrogel wound dressing and its effectiveness in facilitating wound healing, tannic acid (TA), as an antibacterial and antioxidant substance, was incorporated into it. In the second phase, antibacterial activity and animal studies were conducted. The comparison of the CA–based hydrogel with and without TA demonstrated that the TA–containing hydrogel achieved more than 99.9% inhibition and elimination of bacteria. The use of CA–based hydrogel with TA shown in treating burns on the backs of rats caused the wound to close after 17 days, and hair growth was observed by the 21st day. This synthesized flexible hydrogel wound dressing, along with suitable mechanical properties, exceptional antibacterial activity, increased granulation tissue formation, re‐epithelialization, angiogenesis, and collagen deposition, showed good performance in wound healing.