Temperature-Responsive, Injectable Poly(organophosphazene)-Based Hydrogel Adhesive for One-Step Hemostasis and Wound Closure

Their minimally invasive application and adaptability to irregular wounds make injectable hydrogel adhesives attractive for hemostasis and wound closure in surgical and emergency settings. However, current systems suffer from low mechanical strength, weak adhesion, and complex procedures. Here, we propose ADP-PPZ, a single-component, thermoresponsive hydrogel adhesive based on poly(organophosphazene) functionalized with succinimidyl carbonate (SC) groups. ADP-PPZ is readily injectable in its sol state at room temperature (RT), and rapidly gels at body temperature via hydrophobic interactions without external stimuli. Simultaneously, SC groups react with tissue amines, achieving adhesion. The hydrogel exhibits fast gelation (5.5 s), sufficient mechanical strength, effective adhesion (23 kPa), low swelling, biocompatibility, and biodegradability. Moreover compared to PEG-based adhesives, ADP-PPZ demonstrated superior performance, exhibiting rapid hemostasis, stable tissue sealing, re-epithelialization, and collagen remodeling. Collectively, these results establish ADP-PPZ as a novel design strategy that enables independent gelation and tissue adhesion within a single-component hydrogel, offering potential for hemostasis and regenerative applications.