Life is built upon closed-loop feedback and regulation systems that maintain a delicate balance of environmental and metabolic conditions that support cellular function. [1] Bioelectronic devices interface electronic devices with biology with potential for sensing and actuation. [2-5] A challenge for bioelectronic devices is translating between ionic and biochemical signals that dominate biology into electronic currents in the devices and vice versa. Iontronics addresses this challenge by modulating ions directly at the device level rather than electron and holes as in traditional semiconductors. [6] Electrophoretic ion pumps mediate the delivery of ions and charged molecules with an induced electric field [7] to treat epilepsy, [6] chronic pain, [8] inflammation, [9] and to actuate movement in plants. [10] In addition, bioprotonic devices can sense and actuate the flow of H þ in field effect transistors (H þ-FETs), [11,12] enzymatic logic gates, [12] and ion channels. [13] A cell's resting potential, V mem , is an electrical control signal that occurs between the interior of the cell and the extracellular environment regulated by ion channels. [14] In nonexcitable cells, [15] V mem affects cell physiology and functions such as proliferation, differentiation, migration, and apoptosis, as well as cell-cell communication and large-scale morphogenesis. [16] Recently, optically actuated