Self-Supporting Hydrogel Nano/Micro Fibers Mesh for Directional Neuronal Growth

The development of in vitro and in vivo technologies to study neural networks and potential treatments to restore and repair lost neuronal connections has garnered significant attention. These technologies require engineered scaffolds to mimic the physiological characteristics of the tissue's native structure. In this research, we report a 3D-aligned hydrogel nano/microfiber mesh (HNFm) that satisfies the complex requirements of cell culture scaffolds. First, hydrogel nano/microfiber (HNF) dispersion was deposited onto substrates by layer-by-layer assembly and oriented by bar coating. To modulate the mechanical properties and fix the orientation of the HNFm, physical crosslinking methods were employed. Aligned HNFm supports the growth of 3D neural networks with directional alignment along the underlying fibers. In contrast with flat surfaces and randomly oriented scaffolds, aligned HNFm showed spontaneous calcium signal propagation along the anisotropy of the fibers. The oriented axonal growth observed is essential for the study and treatment of peripheral nervous injuries. Our results demonstrate a simple method to obtain engineered scaffolds that mimic complex tissues, ideal for investigating neural connectivity and activity in vitro, with potential applications for in vivo implantation experiments.