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Published on: February 13, 2016
On-demand electrochemically controlled compound release from an ultrasonically powered implant
Max L Wang1, Christian F Chamberlayne2, Haixia Xu3
1Department of Electrical Engineering, Stanford University Stanford CA USA arbabian@stanford.edu.
Abstract:
On-demand drug delivery systems are promising for a wide range of therapeutic applications. When combined with wireless implants for controlled drug delivery, they can reduce overall dosage and side effects. Here, we demonstrate release of fluorescein from a novel on-demand release system for negatively charged compounds. The release system is based on a modified electroresponsive polypyrrole nanoparticulate film designed to minimize ion exchange with the stored compound - a major passive leakage mechanism. We further designed an ultrasonically powered mm-sized implant to electronically control the on-demand drug delivery system in vivo. Release kinetics are characterized both in vitro and in vivo in mice using fluorescein as a model drug, demonstrating the feasibility of wireless, controllable drug release using an ultrasonically powered implant.
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