Electrochemical detection of dopamine using micro- electrodes for neurochemistry studies in rat brains

by Yoga Narasimhan, Padhmodhbhava; Arumugam, Prabhu U.; Oni, Joshua; Fakunle, Eyitayo; Schuhmann, Wolfgang; Woodward, Donald J.; Fritsch, Ingrid

Detection of dopamine (DA) in real time is of significant importance in studies of neurol. disorders like Parkinson's disease, Huntington's disease and Tourette's syndrome, where patients have an imbalance of DA in their brains. DA producing neurons in the substantia nigra of the patients become impaired or die, resulting in low secretion of the neurotransmitter. Measurement of DA is also of interest in understanding psychiatric diseases, such as those with anxiety components. Our goal is to study electrochem. detection of DA using microelectrodes and microscale devices constructed from Low temp. cofired ceramics (LTCC) and silicon. The studies address electrochem. method of detection, device materials, and instrumentation. Microfabrication with various materials as well as different chip and dagger designs has been explored for single and multi- analyte detection. However the signals due to ascorbic acid need to be excluded to avoid overlapping voltammetric response. Hence fast scan cyclic votammetry and use of anionic polymers to coat the electrodes have been explored, to record electrochem. response of DA. We hope that these efforts will lead to real-time monitoring of DA at high spatial resoln. in brain without complications with background subtraction.