Abstract

Despite tremendous research efforts, treatment options for many neurological disorders are inadequate. Systemic drug treatments suffer from side effects and long-term habituation; electrical stimulation is unspecific; and the fluidic injection of drugs often displaces the very cells that are being targeted due to the local pressure increase. Thus, there exists a pressing need to develop novel treatment strategies that overcome these limitations. One such technology is the recently introduced drug delivery platform known as the microfluidic ion pump (µFIP). The µFIP is an implantable device that electrophoretically pumps ions (eg. neurotransmitters, drugs, etc) to the target tissue. In addition to spatial and temporal control, a distinctive feature of the µFIP is that it delivers just the ion and not the solvent and thus does not increase pressure at the outlet. This “dry” delivery is of paramount importance for neural interfacing as it enables an intimate interface between the drug delivery outlet and the target cells. Here we report recent advances in precise engineering to incorporate µFIPs into implantable devices for treating neurological disorders including both depth probes and cortical arrays with recording capabilities. The efficacy of the µFIP platform is demonstrated by stopping epileptic seizures in vivo. This is the first in vivo demonstration of an ion pump for treating a neurological disorder and offers a glimpse of what can be achieved by tailored engineering of the µFIP platform. We anticipate this work to be the starting point for new stimulation, recording and drug delivery paradigms in chronic neural implantation.