Hemoadhican-based self-leveling Janus patch for comprehensive prevention of postoperative adhesions

Postoperative anti-adhesion materials face significant challenges, including dislocation, the induction of nonspecific tissue adhesions, and secondary fibrinolytic disorders. In this study, we developed a self-leveling, transient, unilaterally bonded Janus patch (J-HD) based on hemoadhican (HD). This patch consists of three distinct functional layers: an anti-adhesion layer, a reinforcement layer, and a wet tissue adhesion layer. Each layer serves a specific purpose: the bottom anti-adhesion layer, composed of HD and Pluronic F127 (PF127), effectively prevents cells, proteins, and tissues from adhering; the middle polyvinyl alcohol (PVA) reinforcement layer enhances the mechanical properties of the film, exhibiting a tensile strength of approximately 2.02 MPa; and the top HD adhesion layer provides strong adhesion to wet tissue with an interfacial toughness of approximately 223.85 J/m². The J-HD patches demonstrate excellent self-leveling ability, unilateral adhesion properties, and effective resistance to fibrin and cell adhesion in vitro. In a rat cecum-abdominal wall adhesion model, the J-HD patch exhibited a significant reduction in abdominal adhesions compared to commercially available Interceed® films. Mechanistically, the J-HD patch effectively regulates the fibrinolytic balance by modulating the levels of tissue plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1), promoting a nonadherent state, reducing excessive inflammatory responses, and facilitating the repair of intestinal wall integrity. In vivo implantation of the J-HD patch does not exhibit significant acute or chronic toxicity, elicits a favorable host response, and demonstrates biocompatibility. This study presents a potential strategy for the clinical design of Janus patches with anti-migratory and anti-adhesive properties.