Artificial Action Potential and Ionic Power Device Inspired by Ion Channels and Excitable Cell

Abstract In vivo, the membrane potential of the excitable cell working by ion gradients plays a significant role in bioelectricity generation and nervous system operation. Conventional bioinspired power systems generally have adopted ion gradients, but overlook the functions of ion channels and Donnan effect to generate efficient ion flow in the cell. Here, cell‐inspired ionic power device implementing the Donnan effect using multi‐ions and monovalent ion exchange membranes as artificial ion channels is realized. Different ion‐rich electrolytes on either side of the selective membrane generate the ion gradient potentials with high ionic currents and reduce the osmotic imbalance of the membrane. Based on this device, the artificial neuronal signaling is presented by the mechanical switching system of the ion selectivity like mechanosensitive ion channels in a sensory neuron. Compared with reverse electrodialysis, which requires a low concentration, a high‐power device with ten times the current and 8.5 times the power density is fabricated. This device activates grown muscle cells by increasing power through serial connection like an electric eel, and shows the possibility of an ion‐based artificial nervous system

An advanced 3D lymphatic system for assaying human cutaneous lymphangiogenesis in a microfluidic platform

Abstract The human cutaneous lymphatic system strictly controls lymphatic functions by coordinating with skin cells. The lymphatic system plays important roles in removing cell waste, residual proteins, various antigens, and immune cells from tissues to maintain homeostasis and activate the immune system through the drainage of interstitial fluid1,2. The skin protects our body from external stimuli such as pathogens through the cutaneous lymphatic system3,4. Herein, to develop an in vitro human cutaneous lymphatic model, we present two 3D microfluidic platforms: a lymphangiogenesis model with a precollecting lymphatic vessel-like structure and an advanced lymphangiogenesis model with a functional cutaneous barrier and a precollecting lymphatic vessel-like structure. In addition, we rapidly analyzed prolymphangiogenic effects using methods that incorporate a high-speed image processing system and a deep learning-based vascular network analysis algorithm by 12 indices. Using these platforms, we evaluated the pro-lymphangiogenic effect of Lymphanax, a natural product derived from fresh ginseng. As a result, we demonstrated that Lymphanax induces robust lymphangiogenesis without any structural abnormalities. In conclusion, we suggest that these innovative platforms are useful for studying the interaction between the skin and lymphatic system as well as evaluating the prolymphangiogenic effects of drugs and cosmetics