Collagen-based hydrogel patch promotes renal wound repair

Partial nephrectomy is increasingly becoming the preferred choice for early-stage renal cancer. However, the complex suturing process prolongs warm ischemia time, impairs the function of normal renal parenchyma, and often leads to complications such as wound infection, poor healing, and bleeding. Bioadhesives serve as ideal alternative materials, but currently used medical adhesives, including cyanoacrylates and fibrin/collagen-based glues, suffer from poor wet adhesion and cytotoxicity. Therefore, there is an urgent need to develop multifunctional bioadhesives possessing hemostatic, post-operative wound management, anti-infective, and healing-promoting properties. This study presents a novel integration strategy by incorporating high-purity rat tail collagen (Col) as a multifunctional cross-linking hub and bioactive scaffold into a poly(acrylic acid) (PAAc) and quaternized chitosan (QCS) network via in situ polymerization. This specific formulation yields a pre-formed, stable hydrogel patch that uniquely combines robust tensile strength (172.60 kPa) with a low equilibrium swelling ratio (53.87%)-effectively decoupling these typically conflicting properties. The optimized patch exhibits strong wet tissue adhesion (51.28 kPa), surpassing clinical benchmarks, and demonstrates antimicrobial properties in vitro. In a rat partial nephrectomy model, the patch not only achieved rapid hemostasis but also actively promoted more orderly regeneration of renal tubules, as evidenced by histology and repair-marker expression. This work provides a new material design paradigm for managing complex parenchymal organ wounds.