A multi-ion electrophoretic pump for simultaneous on-chip delivery of H+, Na+, and Cl−

Ions and biomolecules are signal carriers in biological systems and transfer information for intracellular communication and organism function. As such, bioelectronic devices that conduct ions rather than electrons and holes provide an interface to monitor and control physiological processes. These processes often are affected by multiple distinct ionic species. Here, we develop an ion pump that can control the delivery of multiple ionic species on the same chip. We demonstrate on-chip delivery of H + , Na + , and Cl − by monitoring the dynamic concentration change using fluorescent dyes. We integrate the multi-ion pump with machine-learning driven closed-loop control of delivery to ensure precise dose control. The ability to deliver multiple ions with tight control of their concentrations has the potential to finely regulate the extracellular environment and precisely control physiological processes.