Gallol-containing chitosan/hyaluronic acid composite hydrogel patches as wound sealing and dressing materials.

Recently, various adhesive materials have been developed for versatile biomedical applications owing to their rapid and strong adhesion to tissues in water-rich environments. One such example is gallol-containing chitosan (CHI-G), which contains multiple gallol and amine groups in its backbone. However, the practical application of CHI-G alone is limited owing to its intrinsic mechanical strength and undesirable immune responses. In this study, we developed Ca ions- and hyaluronic acid-containing CHI-G (CHC) patches to prevent anastomotic leakage and accelerate wound healing. CHC hydrogel patches showed increased elastic modulus values (809.4 ± 181.7 Pa) compared to that of CHI-G hydrogel patches (137.0 ± 16.3 Pa). In addition, the bursting pressure (78.2 ± 3.5 mmHg) of CHC hydrogel patch-applied porcine intestine was far higher than those of the control (4.13 ± 0.4 mmHg) and HA groups (14.5 ± 2.5 mmHg). CHC hydrogel patches showed suitable mechanical properties and biocompatibility for wound-sealing and dressing applications in water-rich environments. Notably, the CHC hydrogel patch-applied wound healing animal model exhibited a healing rate of over 90 % at 14 days post-surgery, notably higher than that of the control group (76 %). These findings suggest that CHC patches have considerable potential as effective wound dressings and sealing materials.