A Tough Composite Sponge with Controlled PRP Release for Rapid Hemostasis and Pro-Healing in Liver Trauma

Uncontrolled hemorrhage following severe liver trauma remains a critical clinical challenge, as conventional hemostatic agents often fail to simultaneously control diffuse bleeding and actively support subsequent tissue repair. There is a pressing need for biomaterials that integrate immediate hemostasis with pro-healing bioactivity. Here, we report a tough composite sponge (SBC-AG@PRP) designed to address this dual requirement. The scaffold is constructed by incorporating gelatin into a sulfonated bacterial cellulose-alginate matrix, forming a reinforced interpenetrating network that provides exceptional wet-state toughness, rapid shape recovery, and high fluid uptake─properties essential for conforming to dynamically moving liver wounds. This mechanically optimized scaffold serves as a reservoir for platelet-rich plasma (PRP), enabling the sustained release of growth factors over 7 days. In vitro, the released factors reprogram macrophages toward a pro-reparative M2 phenotype and accelerate hepatocyte migration. In a rat model of penetrating liver trauma, SBC-AG@PRP achieves significantly faster hemostasis and reduced blood loss compared to gauze and non-PRP controls. Beyond hemostasis, the controlled release actively modulates the wound microenvironment by dampening inflammation, promoting M2 macrophage polarization, and guiding organized collagen deposition, ultimately facilitating functional liver healing. This work establishes a synergistic strategy that couples mechanical design with sustained biochemical signaling for the management of parenchymal organ injuries.