Micro-Fluidics Neurochemical Analyzer

Intellectual Merit: A major limitation of the technique of in vivo microdialysis involves the analysis of microdialysis fractions using analytical instrumentation. This proposal involves the development of a micro-fluidics neurochemical analyzer that will revolutionize neurochemical recordings with microdialysis by rapidly quantifying multiple analytes with enhanced limits of detection and greatly reduced cost and complexity. The instrument, once developed and optimized, will be capable of inline or off-line analysis of neurochemicals such as glutamate, choline, acetylcholine, GABA, glucose and lactate in samples collected from the brain and spinal cord using microdialysis or other in-vivo sampling techniques. The principle of the technology derives from newly developed microelectrode arrays, which Oan selectively measure neurochemicals of interest through enzymatic micro-layers attached to platinum recording surfaces. The device is based on using dual detector paradigms to subtract interferents and greatly improve signal-to-noise of the measurements. We expect that the resulting inline detectors, when coupled to a modern computer-controlled potentiostat, will have a temporal resolution of 10 second intervals and detection limits close to 10 nanomolar. The resulting instrument will provide biologists and clinicians with an automated analytical instrument having faster sample throughput and greater sensitivity than current instruments such as HPLC coupled with electrochemical detection or capillary electrophoresis coupled with fluorescence detection. In addition, the technology should be more cost-effective in instruments required and their operation when compared to more expensive analytical methodologies that are routinely used in many laboratories. Broader Impacts: The new micro-fluidics neurochemical analyzer will have a big impact in the neurosciences, where large numbers of investigators are using microdialysis sampling techniques that are greatly limited by the analytical methodology to study the temporal properties of neurotransmission in the CNS. A simple Pub-Med search yields greater than 12,000 articles identified by the term microdialysis. The new instrument will have increased temporal resoftition, enhanced sensitivity, rapid sample throughput and lower cost of operation and utilization than current instrumentation. All of these factors will contribute to an instrument that will be widely adopted to accelerate the efforts of biological researchers and clinicians. The proposed development of the micro-fluidics neurochemical analyzer is also critical for the continued education of researchers in rapid recording techniques, as sensitive, versatile, and affordable methods are needed to perform rapid chemical measures in the CNS. We currently interact with a number of scientists who perform neurochemical recordings and this technology will be shared directly with many investigators. Moreover, we conduct training courses on the rapid measurements of neurotransmitters in the CNS that will benefit from this new instrument. Our laboratory is involved with a number of K-12 educational ventures in Kentucky, and chemical recording in the CNS is a particularly effective vehicle to engage these students. Finally, this effort will also strengthen our efforts in educating a significant numbers of women and underrepresented minorities.