Iontronic analog of synaptic plasticity: Hydrogel-based ionic diode with chemical precipitation and dissolution

• DOI: 10.1073/pnas.2211442120
• Publication Date: 2022-12-27T21:25:01Z
• Authors: Seok Hee Han; Sung Il Kim; Min-Ah Oh; Taek Dong Chung
• Keywords: Ions; Neuronal Plasticity; Solubility; Physical Sciences; Long-Term Potentiation; Synapses; Chemical Precipitation; Hydrogels

In this study, an aqueous nonlinear synaptic element showing plasticity behavior is developed, which based on the chemical processes in ionic diode. The device simple, fully ionic, and easily configurable, requiring only two terminals—for input output—similar to biological synapses. key realizing features are precipitation dissolution, occur at forward- or reverse-biased diode junctions appropriate reservoir electrolytes. Given that precipitate acts as a physical barrier circuit, above change conductivity, can be interpreted adjusting “synaptic weight” of system. By varying operating conditions, we first demonstrate four types found system: long-term potentiation/depression short-term potentiation/depression. proposed iontronic has characteristics similar those neural To its potential use comparatively complex information processing, develop precipitation-based synapse (PIS) capable both potentiation depression. Finally, show postsynaptic signals from multiple excitatory inhibitory PISs integrated into total “dendritic” current, function time history, actual hippocampal circuits.