During the long process of wound defect repair, the bioelectric stimulation around the wound gradually decreases, which can cause gradual down-regulation of the wound healing cascade response, disordered deposition of collagen fibers, and abnormal remodeling of the extracellular matrix (ECM). All these combined will eventually result in delayed wound healing and scar tissue formation. To resolve these issues, a novel ZnO nanoparticles modified PVDF/sodium alginate (SA) piezoelectric hydrogel scaffold (ZPFSA) is prepared by 3D printing technology. The prepared ZPFSA scaffold has dual piezoelectric response models, mainly consisting of vertical swelling and horizontal friction, which can be used to simulate and amplify endogenous bioelectricity to promote wound healing and prevent scar formation. Compared with other composite scaffolds, ZPFSA 0.5 (contain 0.5% ZnO nanoparticles) exhibits good biocompatibility, excellent antimicrobial properties, and stable piezoelectric response, so that it can significantly accelerate the wound healing and effectively prevent the scar tissue formation within 2 weeks thanks to the cascade regulation in wound healing, including cell migration, vascularization, collagen remodeling, and the expression of related growth factors. The proposed dual piezoelectric response models will provide a new solution to accelerate wound healing process, prevent scar formation, and extend new application range of piezoelectric materials in wound dressing.
Keywords: 3D printing; electrical stimulation repair; piezoelectric scaffolds; scar prevention.