Acetylcholine, the first neurotransmitter identified in 1914, plays key role in human health and its defects have been associated with neurodegeneration. Elucidating its release dynamics and concentration profiles at the source of its release, the synaptic cleft, is instrumental in understanding neurodegenerative diseases. Here we present our study of acetylcholine synaptic release with a nanoITIES electrode of ~15 nm in radius, unveiling unprecedented details on its release dynamics and concentration profiles around single synaptic cleft. We employed nanoresolved scanning electrochemical microscope (SECM) (1-4) to position the nanoelectrode around the synaptic cleft. We further demonstrate the quantification of acetylcholine single exocytotic events from Aplysia californica neuron cells using a nanoITIES pipet electrode. Development of nanoITIES electrodes for non-redox active transmitter detection will be presented as well. (5-8)

Acknowledgement: This research was supported by the National Institute Neurological Disorders and Stroke of National Institutes of Health under Award Number R21NS085665.

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