A FIBEROPTIC PROBE FOR IN VIVO NEUROTRANSMITTER ANALYSIS

MICRODIALYSIS (MD) IS AN INCREASINGLY IMPORTANT TOOL FOR SAMPLING THE EXTRACELLULAR FLUID OF SPECIFIC REGIONS OF THE BRAIN. REAL-TIME, DIRECT ANALYSIS OF THE MICRODIALYSATEWOULD BE ADVANTAGEOUS FOR STUDYING DYNAMIC CHANGES IN BRAIN CHEMISTRY AS A FUNCTION OF BEHAVIOR OR IN RESPONSE TO EXPERIMENTAL PARADIGMS OR TRAUMA. THE RESEARCH WILL DEVELOP A SURFACE-ENHANCED RAMAN SPECTROSCOPY (SERS) PROBE ON THE TIP OF AN OPTIC FIBER IN DIMENSIONS SUITABLE FOR INSERTION INTO AN IN VIVO MICRODIALYSIS CANNULA. THE SERS/MD PROBE WILL ENABLE IN VIVO ANALYSIS OF NEUROTRANSMITTERS OR OTHER SUBSTANCES IN BRAIN EXTRACELLULAR FLUID BY SERS TECHNIQUES. THE PHASE I OBJECTIVES ARE TO FABRICATE OPTICAL FIBERS WITH SERS SUBSTRATES, COUPLE THEM WITH MICRODIALYSIS CANNULAS, AND DEMONSTRATE DOPAMINE ANALYSIS DURING MICRODIALYSIS FROM A SIMULATED BRAIN EXTRACELLULAR FLUID. SUCCESSFUL DEMONSTRATION OF THE FEASIBILITY OF A SERS/MD PROBE WILL PROVIDE A FOUNDATION FOR PHASE II WORK TO EVALUATE THE PROBEDURING IN VIVO MICRODIALYSIS EXPERIMENTS AND TO DEVELOP A PROTOTYPE SERS/MD PROBE AND INSTRUMENTATION PACKAGE FOR USE IN ACADEMIC, CLINICAL, AND PHARMACEUTICAL NEUROCHEMISTRY LABORATORIES.