posted on 2013-12-06, 00:00authored byElly Sinkala, James E. McCutcheon, Matt Schuck, Eric Schmidt, Mitchell F. Roitman, David T. Eddington
Fast-scan cyclic voltammetry (FSCV) is a common analytical electrochemistry tool used to measure chemical species. It has recently been adapted for measurement of neurotransmitters
such as dopamine in awake and behaving animals (in vivo). Electrode calibration is an essential
step in FSCV to relate observed current to concentration of a chemical species. However,
existing methods require multiple components, which reduce the ease of calibrations. To this
end, a microfluidic flow cell (μFC) was developed as a simple device to switch between buffer
and buffer with a known concentration of the analyte of interest – in this case dopamine - in a
microfluidic Y-channel. The ability to quickly switch solutions yielded electrode calibrations
with faster rise times and that were more stable at peak current values. The μFC reduced the
number of external electrical components and produced linear calibrations over a range of
concentrations. To demonstrate this, an electrode calibrated with the μFC was used in FSCV
recordings from a rat during the delivery of food reward – a stimulus that reliably evokes a brief
increase in current due to the oxidation of dopamine. Using the linear calibration, dopamine
concentrations were determined from the current responses evoked during the behavioral task.
The μFC is able to easily and quickly calibrate FSCV electrode responses to chemical species for
both in vitro and in vivo experiments.
Funding
Support for this work was provided by NIH MH085073 and NIH R01 DA025634 to MFR
History
Publisher Statement
Post print version of article may differ from published version. The definitive version is available through Royal Society of Chemistry at DOI: 10.1039/c2lc40168a