Injectable multifunctional sponges with rough sieve structure and efficient shape-recoverability for small-sized...

The emergence of special scenarios involving small-sized penetrating wounds has imposed stricter performance requirements on shape-recovery hemostatic materials, particularly regarding their shape fixity and water-triggered shape recovery efficiency. Herein, an efficient shape-recovery sponge dressing with high shape fixity and high-speed liquid absorption, designated as CQT, was developed by integrating a sieve structure with the rough surface coating. The sieve structure, characterized by microporous structures on macroporous walls, enhanced the multi-level and connectivity of the overall pore network, which could improve compressive fixity via enhancing the energy dissipation required for rebound and enabled efficient shape recovery through augmented capillary action during fluid absorption. Concurrently, the enhanced pore connectivity promoted rapid blood absorption (<0.5 s), expanded interfacial contact between blood and hydrophilic pore walls, and improved interception of blood active components, while the rough coating on the pore walls provided more binding sites along with its charge effect to enhance the adhesion and aggregation of blood cells (BCI of 7.8 %). The excellent in vivo hemostatic performance of the sponge (blood loss of 0.31 g and hemostasis time of 63 s) was further validated using a rat liver defect model, suggesting its potential for application in small-sized penetrating wounds. Additionally, this coating has antimicrobial and antioxidant properties that help to prevent infection and reduce inflammation. Thus, the unique sponge dressings possess excellent initial shape adaptability and efficient expansion hemostatic ability, making it very suitable for emergency hemostasis and subsequent repair of small-sized penetrating wounds.