Nanofluidic-based electrochemical pump for remotely controlled, on-demand drug delivery

Abstract

Implantable drug delivery systems offer the promise of on-demand, tunable release profiles tailored to individual therapeutic needs. Here, we present a nanofluidic membrane-based electrochemical delivery system that leverages controlled in situ gas generation to achieve electrically modulated molecular transport. The device comprises a monolithically fabricated nanochannel membrane coated with a platinum layer, which enables cathodic water reduction upon application of a −2 VDC potential. This process generates bubbles that transiently increase local pressure, enhancing convective drug transport through the nanochannels. Electrochemical characterization revealed stable gas evolution dynamics with an average actuation current of 2.31 ± 0.36 mA and low power requirements (4.62 ± 0.43 mW), highlighting suitability for energy-constrained implantable settings. In vitro and simulated physiological clearance studies demonstrated reversible, voltage-dependent modulation of drug release across a range of compounds with diverse hydrodynamic radii and charges. Drug release rates ranged from 1 to 10 μg h⁻¹ under electrical actuation—values within therapeutically relevant dosing windows for a wide array of clinical applications. Integration and in vitro validation with a miniaturized Bluetooth-enabled printed circuit board (PCB) controller powered by a 3 V coin cell battery further supports the platform's feasibility for autonomous, wirelessly controlled therapeutic administration. Together, these findings demonstrate a scalable, low-power, and highly adaptable nanofluidic system capable of tunable drug delivery, suitable for integration within implantable closed-loop systems.