We will build miniature. solid-state pumps for medicine. These pumps are intended for eventual use as indwelling prostheses in patients needing long-term. controlled delivery of drug into a specific organ or tissue. Our pumps are piezoelectric de vices, just over one mm in diameter. They give precise, programmed delivery of very small, I-2pl drug volumes. They can therefore be used as indwelling chemical stimulators for delivering drugs to small targets like brain nuclei or blood vessels. One important use now emerging would be delivery of neurotrophic growth factors directly into ailing or damaged brain nuclei. We showed in Phase I that piezoelectric pumps work well with biomedically-relevant fluids; we built and characterized two types of piezoelectric pumps for biomedicine. In Phase II we will design and build pro to types of implantable systems that include pump, drug reservoir, fluid delivery microchannels, and drug dialysis tips. To capitalize on the benefits of small size and precision pumping we will design our prototype for use as an intracranial "neuroprosthetic" drug pump, suitable for dopamine replacement therapy (and/or growth factor therapy) in Parkinson's disease. In Phase III we will provide pumping systems to selected members of the neuroscience community for beta-site evaluation in animal. PROPOSED COMMERCIAL APPLICATION: The technology we are developing can lead to a whole new class of chemical-stimulation prosthetic devices in medicine. In the neuroprosthetic market alone there are about 500,000 patients with Parkinson's, and hundreds of thousands more with other diseases amenable to our chemical microstimulation treatment, such as epilepsy chronic pain, Alzheimer's, and cancer