An integrated Janus antibacterial hydrogel with rapid photoresponsive adhesive/tough anti-adhesive bi-layer for enhanced wound healing and suppression of postoperative tissue adhesion.

The Janus adhesive wound dressings exhibit properties analogous to human skin. Specifically, they must possess both adhesive and non-adhesive characteristics to function effectively. The adhesive property ensures secure attachment to the wound site, while the non-adhesive side acts as a protective barrier against external contaminants. In this study, we have developed an integrated Janus antibacterial hydrogel that features a rapid photoresponsive adhesive layer alongside a robust anti-adhesive layer. The anti-adhesion layer hydrogel, referred to as PPAL, exhibits a maximum tensile fracture strength of 738.54 kPa and a fracture strain of 774.02 %. This adhesive layer is referred to as MCDAE. Upon irradiation with 405 nm ultraviolet light, MCDAE rapidly forms a strong bond with PPAL within 10 s, resulting in the formation of a Janus-adhesive hydrogel (MCDAE/PPAL). We synthesized silver nanoparticles (AgNPs) with sizes ranging from 20 to 40 nm in situ within MCDAE hydrogels. Owing to the synergistic effects of quaternary ammonium compounds and AgNPs, Janus MCDAE/PPAL hydrogels exhibited concentration-dependent bacteriostatic activity against both Escherichia coli and Staphylococcus aureus. Furthermore, both in vitro and in vivo experiments have demonstrated that the MCDAE/PPAL dressing possesses superior biocompatibility, exceptional antibacterial properties, effective hemostatic capabilities, and enhanced wound healing potential.