One-pot fabrication of high-strength Janus hydrogel for wet tissue hemostasis and intestinal/intrauterine anti-adhesion

Existing Janus hydrogels struggle to integrate high mechanical strength, bilateral asymmetric adhesion, and a simple fabrication process. Herein, we report a one-pot strategy for rapid fabrication of integral high-strength Janus hydrogels, leveraging the heterogeneous aggregation of carboxyl groups induced by sodium lignosulfonate. We characterize gelation within only 5 minutes, robust mechanical properties and bilateral asymmetric adhesion. We demonstrate that the hydrogel achieves rapid hemostasis as an emergency hemostatic patch across multiple organs in rats and Bama pigs. We show that it exhibits strong unilateral adhesion to damaged intestinal and endometrial tissues, promoting wound healing and reducing postoperative adhesion compared to sutures and commercial adhesives. Given its straightforward one-pot preparation, high mechanical strength, and effective asymmetric wet tissue adhesion, the Janus hydrogel offers a feasible and practical design for next-generation bio-adhesives, highlighting its potential as a suture alternative for internal wound repair.