Supramolecular nanogel aggregate as injectable regulatory barrier for preventing postoperative adhesion in diabetic colonic anastomosis.

Postoperative tissue adhesions, especially after intestinal surgeries like colonic anastomosis, frequently cause serious complications such as intestinal obstruction and chronic pain, which are worsened in diabetic conditions. Although barrier materials have advanced, it remains challenging to simultaneously achieve targeted localization, dynamic mechanical adaptability, anti-adhesion efficacy, and bio-regulatory functions. Here, we develop an injectable supramolecular aggregate barrier formed by aggregation-induced gelation of thermosensitive amphoteric nanogels. The resulting aggregate possesses high structural stability and dynamic mechanical properties, showing stable tissue adhesion and conformability to irregular surfaces to create a stable, displacement-resistant barrier. We demonstrate that this supramolecular aggregate inhibits fibroblast and bacterial adhesion, modulates local inflammation, and significantly reduces adhesions in a diabetic rat model of colonic anastomosis compared to commercial anti-adhesion materials. Through precise molecular engineering, it reconciles the conflict between tissue adhesion and postoperative anti-adhesion while providing antibacterial and immunomodulatory activities. This work offers a promising strategy for designing advanced anti-adhesion biomaterials suited for complex surgical and metabolic conditions.