Chitosan and cellulose nanofiber-reinforced collagen membrane for effective Abdominal Wall hernia repair

In abdominal wall hernia repair, current mainstream polypropylene (PP)-based patches face challenges such as chronic inflammation, mismatched degradation rates, and insufficient anti-deformation properties. While natural biomaterials offer good biocompatibility and degradability, their clinical application is limited by insufficient mechanical strength. To overcome this challenge, we engineered a chitosan (CS) and cellulose nanofiber (CNF)-reinforced collagen membrane. This design leveraged dual polysaccharide functionalities: CNF provided nanoscale reinforcement, while CS enabled multi-point cross-linking with collagen, synergistically enhancing the membrane's structural stability. To further enhance performance, a sequential approach involving the layer-by-layer blade-coating and induced assembly was employed, producing stacked and oriented lamellar structures. The optimized membrane exhibited raised tensile strength (49.00 MPa) and fracture energy (121.22 MJ/m 3 ), prolonged degradation period (52.7 % weight retention at 28 days), and reduced swelling rate (135.5 %). In vitro biocompatibility assays confirmed the material's non-cytotoxicity and excellent blood compatibility. Moreover, in vivo rat abdominal defect models demonstrated superior tissue regeneration, minimized inflammation, and effective mechanical support when using the developed membrane compared to PP meshes and pure collagen membranes (COL). These findings highlight the potential of this green strategy to provide a balanced solution for hernia repair, addressing both mechanical and biological requirements.