Treatment of wounds in special areas is challenging due to inevitable movements and difficult fixation. Common cotton gauze suffers from incomplete joint surface coverage, confinement of joint movement, lack of antibacterial function, and frequent replacements. Hydrogels have been considered as good candidates for wound dressing because of their good flexibility and biocompatibility. Nevertheless, the adhesive, mechanical, and antibacterial properties of conventional hydrogels are not satisfactory. Herein, cationic polyelectrolyte brushes grafted from bacterial cellulose (BC) nanofibers are introduced into polydopamine/polyacrylamide hydrogels. The 1D polymer brushes have rigid BC backbones to enhance mechanical property of hydrogels, realizing high tensile strength (21–51 kPa), large tensile strain (899–1047%), and ideal compressive property. Positively charged quaternary ammonium groups of tethered polymer brushes provide long‐lasting antibacterial property to hydrogels and promote crawling and proliferation of negatively charged epidermis cells. Moreover, the hydrogels are rich in catechol groups and capable of adhering to various surfaces, meeting adhesive demand of large movement for special areas. With the above merits, the hydrogels demonstrate less inflammatory response and faster healing speed for in vivo wound healing on rats. Therefore, the multifunctional hydrogels show stable covering, little displacement, long‐lasting antibacteria, and fast wound healing, demonstrating promise in wound dressing.

layers has attracted remarkable attention in recent years for surgical challenge and undesirable treatment outcomes. The destruction of the muscular layer is difficult to be sutured and injury of the serosal membrane could induce obvious viscera adhesion. [5,6] In the past few decades, tension-free repair operation is recommended as the standard treatment for soft-tissue defects like abdominal wall defects, in which different types of patches have been widely used. [1,[7][8][9] Traditional synthetic meshes with high strength, light weight, and anti-deformation (e.g., polypropylene (PP) and polyester meshes) have been widely used for tension-free repair of soft-tissue defects. But these meshes could result in severe visceral adhesion and undesirable wound healing, because of an obvious foreign body reaction (Figure 1a). [10][11][12] One of the most common approaches to solve the problem of visceral adhesion is to develop composite patches with anti-adhesion barriers. [9,13] For example, Parietex composite (PCO) mesh has been successfully designed to prevent visceral adhesion by coating an anti-adhesive collagen-based barrier on polyester mesh. [14,15] Nevertheless, these polyester or PP-based composite meshes could cause undesirable wound healing, due to their inherent unsatisfied inflammation response and lack of suitable microstructure for cells to migrate and grow. [16,17] Moreover, the collagen-based barrier would swell and cause deformation of composite meshes in an abdominal wet environment [18] (Figure 1b). Currently, the Implantable meshes used in tension-free repair operations facilitate treatment of internal soft-tissue defects. However, clinical meshes fail to achieve anti-deformation, anti-adhesion, and pro-healing properties simultaneously, leading to undesirable surgery outcomes. Herein, inspired by the peritoneum, a novel biocompatible Janus porous poly(vinyl alcohol) hydrogel (JPVA hydrogel) is developed to achieve efficient repair of internal soft-tissue defects by a facile yet efficient strategy based on top-down solvent exchange. The densely porous and smooth bottom-surface of JPVA hydrogel minimizes adhesion of fibroblasts and does not trigger any visceral adhesion, and its loose extracellular-matrix-like porous and rough top-surface can significantly improve fibroblast adhesion and tissue growth, leading to superior abdominal wall defect treatment to commercially available PP and PCO meshes. With unique anti-swelling property (maximum swelling ratio: 6.4%), JPVA hydrogel has long-lasting anti-deformation performance and maintains high mechanical strength after immersion in phosphate-buffered saline (PBS) for 14 days, enabling tolerance to the maximum abdominal pressure in an internal wet environment. By integrating visceral anti-adhesion and defect pro-healing with anti-deformation, the JPVA hydrogel patch shows great prospects for efficient internal soft-tissue defect repair.

In guided bone regeneration surgery, a barrier membrane is usually used to inhibit soft tissue from interfering with osteogenesis. However, current barrier membranes usually fail to resist the impact of external forces on bone‐augmented region, thus causing severe displacement of membranes and their underlying bone graft materials, eventually leading to unsatisfied bone augmentation. Herein, a new class of local double‐layered adhesive barrier membranes (ABMs) is developed to successfully immobilize bone graft materials. The air‐dried adhesive hydrogel layers with suction‐adhesion properties enable ABMs to firmly adhere to the wet bone surface through a “stick‐and‐use” band‐aid‐like strategy and effectively prevent the displacement of membranes and the leakage of bone grafts in uncontained bone defect treatment. Furthermore, the strategy is versatile for preparing diverse adhesive barrier membranes and immobilizing different bone graft materials for various surgical regions. By establishing such a continuous barrier for the bone graft material, this strategy may open a novel avenue for designing the next‐generation barrier membranes.