Autonomous Microcapillary Drug Delivery System Self-Powered by a Flexible Energy Harvester

Abstract

Implantable bioelectronic devices pave the way for novel biomedical applications operating at high spatiotemporal resolution, which is crucial for neural recording and stimulation, drug delivery, and brain-machine interfaces. Before successful long-term implantation and clinical applications, these devices face a number of challenges, such as mechanical and operational stability, biocompatibility, miniaturization, and powering. To address two of these crucial challenges-miniaturization and powering-the development and characterization of an electrophoretic drug delivery device, manufactured inside fused quartz fibers (outer diameter of 125 mu m), which is self-powered by a flexible piezoelectric energy harvester, are reported. The resulting device-the first integration of piezoelectric charging with "iontronic" delivery-exhibits a high delivery efficiency (number of neurotransmitters delivered per charges applied) and a direct correlation between the piezoelectric charging and the amount delivered (number of dynamic bends versus pmols delivered).