Photocurable antibacterial bioadhesives derived from itaconated polyhydroxyurethane prepolymer and partially methacrylated tannic acid

Abstract

In response to the growing need for effective and safe biomedical adhesives, this study focuses on developing a photocurable antibacterial bioadhesive derived from innovative and sustainable materials. A soybean oil-based polyhydroxyurethane was synthesized and functionalized via reaction with itaconic anhydride. Tannic acid, a biobased polyphenolic compound selected for its adhesion-promoting and antibacterial properties, underwent a partial methacrylation reaction to yield tannic acid methacrylate. Combining these compounds, in the appropriate composition with a photoinitiator, multifunctional thiol and a reactive diluent, led to the development of a thiol–ene photopolymerizable system. Fourier transform infrared and 1H NMR spectroscopic methods were used to characterize these materials. The potential of this light-curable system as an antibacterial bioadhesive was assessed through various assays. The bioadhesives exhibited a high gel content of 98% in water and 85% in tetrahydrofuran, and a sharp, uniform tan δ peak, confirming the successful formation of a homogeneous network structure. Suitable adhesion strength (331 kPa) to gelatin sheets, a tissue-mimicking substrate, and surface free energy values of 52–58 mN m−1 demonstrated effective thermodynamic adhesion to skin tissue. Furthermore, the viability of approximately 88% for L-929 fibroblast cells cultured with these bioadhesives confirmed their nontoxicity. Additionally, the bioadhesives showed moderate to good antimicrobial activity against S. aureus (72% killing) and E. coli (46% killing) bacteria. © 2025 Society of Chemical Industry. © 2025 Society of Chemical Industry.