Measurement of Basal Neurotransmitter Levels Using Convolution-Based Nonfaradaic Current Removal

Area of Science:

• Neuroscience
• Analytical Chemistry
• Electrochemistry

Background:

• Fast-scan cyclic voltammetry (FSCV) enables subsecond in vivo neurotransmitter measurements.
• Current FSCV limitations, like background subtraction, restrict analysis to phasic release, hindering basal level studies.
• Isolating neurotransmitter redox signals from background current is crucial for studying basal levels.

Purpose of the Study:

• To evaluate a convolution-based method for direct analytical signal isolation in FSCV.
• To optimize FSCV protocols for improved background current prediction.
• To demonstrate the measurement of in vivo basal dopamine concentrations.

Main Methods:

• Optimized FSCV protocols, including applied waveform and carbon-fiber type (pitch-based).
• Utilized holding potentials of at least 0.0 V to simplify background currents.
• Applied a convolution-based method to predict and subtract the background signal.

Main Results:

• Protocol modifications simplified background currents for convolution prediction.
• Pitch-based carbon fibers and specific holding potentials improved background prediction accuracy.
• Demonstrated successful in vivo measurement of basal dopamine levels with controlled electrode states.

Conclusions:

• The convolution-based method enables direct isolation of analytical signals in FSCV.
• Optimized protocols enhance the accuracy of background current prediction.
• This approach expands FSCV capabilities for measuring in vivo basal neurotransmitter dynamics, particularly dopamine.