Asymmetric Adhesive and Absorbable Fiber Membrane of Methacrylated Gelatin–Gelatin/Acetylcysteine for Advanced Hemostatic Applications

Conventional hemostatic methods often exhibit limited efficacy in complex surgical scenarios, prompting the development of absorbable hemostatic materials like gelatin sponges. These absorbable materials can be metabolized by the body, obviating the requirement for secondary surgeries for removal and minimizing foreign body reactions. However, existing materials suffer from notable limitations, including suboptimal hemostatic performance, excessive volumetric expansion, and a lack of balanced site-specific tissue adhesion with nonadherence to surrounding structures. In this study, the methacrylated gelatin–gelatin/acetylcysteine (GelMA-Gel/NAC) asymmetric adhesive fiber membrane was constructed by electrospinning technology. The GelMA layer on the outside was the key structural component, characterized by a significant specific surface area and remarkable water absorbency (1724.02 ± 123.40%), achieving high-efficiency hemostasis. Despite lacking adhesive properties, this design effectively prevented adhesion to surrounding tissues. On the contrary, the inner Gel/NAC7.5:10 can firmly adhere to the wet tissue surface (1.35 ± 0.03 kPa, 16.49 ± 4.19 J/m2) to prevent the dressing from falling off. Compared with commercial dressings such as gelatin sponge, the double-layer membrane showed reduced BCI (7.12 ± 2.05%), diminished blood loss (126 ± 76 mg, femoral artery model), and accelerated hemostasis (35 ± 4 s, femoral artery model). Furthermore, the material exhibited excellent biodegradation kinetics with complete in vivo resorption within 30 days and demonstrated excellent biocompatibility, as no significant histopathological changes were observed in major organs. These findings indicate its considerable potential for clinical translation as a next-generation surgical hemostatic material.