Quantitative Measurement of Transmitters in Individual Vesicles in the Cytoplasm of Single Cells with Nanotip Electrodes

Li Xianchan; Soodabeh Majdi; Johan Dunevall; Hoda Mashadi Fathali; Andrew Ewing

doi:10.1002/anie.201504839

Quantitative Measurement of Transmitters in Individual Vesicles in the Cytoplasm of Single Cells with Nanotip Electrodes
Journal article, 2015

The quantification of vesicular transmitter content is important for studying the mechanisms of neurotransmission and malfunction in disease, and yet it is incredibly difficult to measure the tiny amounts of neurotransmitters in the attoliter volume of a single vesicle, especially in the cell environment. We introduce a novel method, intracellular vesicle electrochemical cytometry. A nanotip conical carbon-fiber microelectrode was used to electrochemically measure the total content of electroactive neurotransmitters in individual nanoscale vesicles in single PC12 cells as these vesicles lysed on the electrode inside the living cell. The results demonstrate that only a fraction of the quantal neurotransmitter content is released during exocytosis. These data support the intriguing hypothesis that the vesicle does not open all the way during the normal exocytosis process, thus resulting in incomplete expulsion of the vesicular contents.

Carbon fibers

Carbon

Conical carbon

Neurophysiology

Quantitative measurement

catecholamines

Electrodes

Nanotips

vesicles

exocytosis

electrochemistry

Nano-electrodes

Intracellular vesicles

Microelectrodes

Electroactive neurotransmitters

nanoelectrodes

Transmitters