Biomimetic collagen patches with armor-like flexibility and strength for hernia repair

Abdominal hernia repair is essential for restoring abdominal wall integrity and preventing visceral protrusion; however, current patch materials struggle to reconcile mechanical durability with biological integration, giving rise to a fundamental contradiction between long-term support and degradation-regeneration. Inspired by fish scales, we developed a biomass-based composite patch (COL/γ-PGA/CNF/CS-G) via collagen self-assembly, biomimetic gradient mineralization, and multi-point cross-linking (EDC/NHS). This strategy integrates layer-by-layer blade-coating and controlled phosphate deposition to create a mineral gradient emulating natural fish scales. Mechanical testing revealed that COL/γ-PGA/CNF/CS-G exhibited superior comprehensive mechanical properties (tensile strength: 5.02 ± 0.40 MPa, burst strength: 597.17 ± 11.49 kPa) and enhanced flexibility (twist angle: 1800°) compared to unmineralized (COL/γ-PGA/CNF/CS-C) and pure collagen membrane (COL) materials. Notably, COL/γ-PGA/CNF/CS-G maintained a high mechanical strength (tensile strength: 1.27 ± 0.18 MPa) after 7 days of enzymatic degradation in a simulated physiological condition, thereby offering stable support during tissue repair processes. In vitro evaluations indicated that COL/γ-PGA/CNF/CS-G was more conducive to cell proliferation and regeneration than PP mesh. In vivo animal experiments demonstrated that COL/γ-PGA/CNF/CS-G effectively promoted tissue repair and regeneration while reducing the formation of visceral adhesions. These findings underscore that the biomimetic flexible armor-like biomass-based patch provides a facile and effective strategy for abdominal wall hernia repair.