A fiber-reinforced bioresponsive hierarchical tampon-inspired dressing orchestrates synergistic hemostasis and controlled antioxidant delivery for female reproductive tract repair.

The effective repair of female reproductive tract (FRT) mucosal injuries is a significant clinical challenge, often hindered by the poor mechanical integrity and uncontrolled drug release profiles of conventional biomaterials. To address these limitations, a hierarchical "system-in-a-system" dressing, [CC@La]-$-[CP@F], was engineered entirely from natural polysaccharides. This integrated platform combines a mechanically robust primary scaffold with a secondary therapeutic delivery system. The primary scaffold, a fiber-reinforced sponge (CP@F), was fabricated via a pH-responsive Schiff base reaction between carboxymethyl chitosan and oxidized pullulan, followed by lyophilization. The incorporation of chitosan fibers resulted in a nearly three-fold increase in compressive strength to 348.97 kPa, transforming the fragile matrix into a resilient, load-bearing structure with excellent shape-memory and injectability. Embedded within this sponge are antioxidant (α-lipoic acid)-loaded microspheres (CC@La), engineered using Layer-by-Layer assembly. This dual-barrier architecture effectively suppresses burst release, enabling a sustained, multi-day therapeutic delivery specifically triggered by the acidic wound microenvironment (pH 5.5). The engineered composite demonstrated superior hemostatic efficacy in challenging in vivo models, including non-compressible liver hemorrhage, reducing bleeding time by over 55% compared to commercial gelatin sponges. Furthermore, the dressing exhibited potent, broad-spectrum antimicrobial activity (>99% efficacy) and antioxidant capacity. In a rat model of FRT mucosal injury, the multifunctional dressing significantly accelerated wound closure and promoted high-quality, regenerative healing, characterized by complete re-epithelialization and organized collagen deposition. This work presents a comprehensive engineering strategy, demonstrating how integrating mechanical reinforcement with programmed, multi-stage therapeutic action can orchestrate the entire wound healing cascade.