Enoki-Inspired Microfibers and Extracellular Matrix Enhance Biaxially Interlocking Interfaces

Taking inspiration from diverse interlocking and adhesion structures found in nature, a biaxially interlocking interface is developed in this work. This interface is formed by interconnecting two electrostatically flocked substrates and its mechanical strength is enhanced through the incorporation of enoki mushroom-shaped microfibers and deposited extracellular matrix (ECM). Tips of flocked straight fibers can be transformed into mushroom shapes through thermal treatment. The tensile strength of interlocked scaffolds with mushroom-shaped tips drastically increased when compared to scaffolds made of straight fibers, which was not reported previously. More cells proliferate within interlocked scaffolds with mushroom-shaped tips than scaffolds with straight fibers. Additionally, the mechanical strength (e.g., compressive, tensile, and shear) of cell-seeded interlocked scaffolds increased proportionally to the amount of ECM deposited by dermal fibroblasts. The biaxially interlocking interface developed in this study holds promise for applications in engineering interfacial tissues, modelling tissue interfaces, investigating tissue-tissue interactions, and facilitating tissue bridging or binding.