Characterization of local pH changes in brain using fast-scan cyclic voltammetry with carbon microelectrodes.

Transient local pH changes in the brain are important markers of neural activity that can be used to follow metabolic processes that underlie the biological basis of behavior, learning and memory. There are few methods that can measure pH fluctuations with sufficient time resolution in freely moving animals. Previously, fast-scan cyclic voltammetry at carbon-fiber microelectrodes was used for the measurement of such pH transients.

Microfabricated FSCV-compatible microelectrode array for real-time monitoring of heterogeneous dopamine release.

Fast scan cyclic voltammetry (FSCV) has been used previously to detect neurotransmitter release and reuptake in vivo. An advantage that FSCV has over other electrochemical techniques is its ability to distinguish neurotransmitters of interest (i.e.

Enhancing Electrochemical Detection by Scaling Solid State Nanogaps.

The ability to quickly and inexpensively fabricate planar solid state nanogaps has enabled research to be effectively performed on devices down to just a few nanometers. Here, nanofabricated electrode pairs with electrode-to-electrode spacings of <4, 6 and 20 nm are utilized for monitoring an electroactive molecules, dopamine, in ionic solution. The results show a several order of magnitude enhancement of the electrochemical signal, collected current, for the solid state nanogaps with 6 nm electrode-electrode spacings as compared to traditional microelectrodes.

Carbon microelectrodes with a renewable surface.

Electrode fouling decreases sensitivity and can be a substantial limitation in electrochemical experiments. In this work we describe an electrochemical procedure that constantly renews the surface of a carbon microelectrode using periodic triangle voltage excursions to an extended anodic potential at a scan rate of 400 V s(-1). This methodology allows for the regeneration of an electrochemically active surface and restores electrode sensitivity degraded by irreversible adsorption of chemical species.

Simultaneous monitoring of dopamine concentration at spatially different brain locations in vivo.

When coupled with a microelectrode, background-subtracted fast scan cyclic voltammetry (FSCV) allows fast, sensitive and selective determination of analytes within a small spatial location. For the past 30 years experiments using this technique have been largely confined to recordings at a single microelectrode. Arrays with closely separated microelectrodes would allow researchers to gain more informative data as well as probe regions in close spatial proximity.

Simultaneous decoupled detection of dopamine and oxygen using pyrolyzed carbon microarrays and fast-scan cyclic voltammetry.

Microfabricated structures utilizing pyrolyzed photoresist have been shown to be useful for monitoring electrochemical processes. These previous studies, however, were limited to constant-potential measurements and slow-scan voltammetry. The work described in this paper utilizes microfabrication processes to produce devices that enable multiple fast-scan cyclic voltammetry (FSCV) waveforms to be applied to different electrodes on a single substrate.

Electrochemical Dopamine Detection: Comparing Gold and Carbon Fiber Microelectrodes using Background Subtracted Fast Scan Cyclic Voltammetry.

Electrochemical detection is becoming increasingly important for the detection of biological species. Most current biological research with electrochemical detection is done with carbon fiber electrodes due to their many beneficial properties. The ability to build electrochemical sensor from noble metals instead of carbon fibers may be beneficial in developing inexpensive multiplexed electrochemical detection schemes.