Fast-scan controlled-adsorption voltammetry for the quantification of absolute concentrations and adsorption dynamics.

Fast-scan cyclic voltammetry has depended on background subtraction to quantify small changes in neurotransmitter concentration. Because of this requirement, measurements of absolute concentrations using fast-scan cyclic voltammetry have been limited. Here we develop and characterize fast-scan controlled-adsorption voltammetry (FSCAV), which enables direct measurements of absolute concentrations in vitro without the use of flow injection to change the concentration. This enables probing the diffusion-controlled adsorption dynamics of biogenic amines and other adsorbing species. An implicit finite-difference model of mass-transport-limited adsorption was developed and is in agreement with experimental results. Optimization of FSCAV yielded a sensitivity of 81 ± 11 nA/μM for dopamine, corresponding to a limit of detection of 3.7 ± 0.5 nM. Through the combination of novel instrumentation and validated computer simulations, we show that FSCAV is an important measurement tool that can be used to determine absolute concentrations and study mass-transport-limited adsorption.

[1]  I. Langmuir.  THE CONSTITUTION AND FUNDAMENTAL PROPERTIES OF SOLIDS AND LIQUIDS , 1917 .

[2]  Michael F Santillo,et al.  Trends in computational simulations of electrochemical processes under hydrodynamic flow in microchannels , 2011, Analytical and bioanalytical chemistry.

[3]  Pavel Takmakov,et al.  Higher sensitivity dopamine measurements with faster-scan cyclic voltammetry. , 2011, Analytical chemistry.

[4]  Werner G. Kuhr,et al.  Background subtraction for rapid scan voltammetry , 1986 .

[5]  Parastoo Hashemi,et al.  Brain dopamine and serotonin differ in regulation and its consequences , 2012, Proceedings of the National Academy of Sciences.

[6]  Parastoo Hashemi,et al.  Ultrafast detection and quantification of brain signaling molecules with carbon fiber microelectrodes. , 2012, Analytical chemistry.

[7]  Eric W. Kristensen,et al.  Dispersion in flow injection analysis measured with microvoltammetric electrodes , 1986 .

[8]  M. Armstrong‐James,et al.  Polarographic assay of iontophoretically applied dopamine and low-noise unit recording using a multibarrel carbon fibre microelectrode , 1981, Brain Research.

[9]  Werner G. Kuhr,et al.  Real-time measurement of dopamine release in rat brain , 1986, Brain Research.

[10]  R. Wightman,et al.  Fast-scan cyclic voltammetry of 5-hydroxytryptamine. , 1995, Analytical chemistry.

[11]  Keith B. Oldham,et al.  Convolution: a general electrochemical procedure implemented by a universal algorithm , 1986 .

[12]  Jinwoo Park,et al.  In vivo voltammetric monitoring of norepinephrine release in the rat ventral bed nucleus of the stria terminalis and anteroventral thalamic nucleus , 2009, The European journal of neuroscience.

[13]  R. Wightman,et al.  Sources contributing to the average extracellular concentration of dopamine in the nucleus accumbens , 2012, Journal of neurochemistry.

[14]  P. Kissinger,et al.  Voltammetry in brain tissue--a new neurophysiological measurement. , 1973, Brain research.

[15]  R. Wightman,et al.  Fast-scan voltammetry of biogenic amines. , 1988, Analytical chemistry.

[16]  I. Trachtenberg,et al.  Adsorption Kinetics and Electrode Processes. , 1958 .

[17]  Michael L Heien,et al.  Rethinking data collection and signal processing. 1. Real-time oversampling filter for chemical measurements. , 2012, Analytical chemistry.

[18]  Ralph N. Adams,et al.  In vivo electrochemical measurements in the CNS , 1990, Progress in Neurobiology.

[19]  K. Jennings.  A comparison of the subsecond dynamics of neurotransmission of dopamine and serotonin. , 2013, ACS chemical neuroscience.

[20]  R. Wightman,et al.  Monitoring rapid chemical communication in the brain. , 2008, Chemical reviews.

[21]  R. Wightman,et al.  Resolving neurotransmitters detected by fast-scan cyclic voltammetry. , 2004, Analytical chemistry.

[22]  L. Rogers,et al.  Polarographic Studies with Gold, Graphite, and Platinum Electrodes , 1954 .

[23]  Pavel Takmakov,et al.  Carbon microelectrodes with a renewable surface. , 2010, Analytical chemistry.

[24]  B. J. Venton,et al.  Carbon-fiber microelectrodes for in vivo applications. , 2009, The Analyst.

[25]  Jonathan A. Stamford,et al.  Fast cyclic voltammetry: improved sensitivity to dopamine with extended oxidation scan limits , 1990, Journal of Neuroscience Methods.

[26]  Garret D Stuber,et al.  Overoxidation of carbon-fiber microelectrodes enhances dopamine adsorption and increases sensitivity. , 2003, The Analyst.

[27]  K. B. Oldham.  Convolution of voltammograms as a method of chemical analysis , 1986 .

[28]  A. Fick.  On liquid diffusion , 1995 .

[29]  R. McCreery,et al.  Control of Electron Transfer Kinetics at Glassy Carbon Electrodes by Specific Surface Modification , 1996 .

[30]  R. Wightman,et al.  Subsecond adsorption and desorption of dopamine at carbon-fiber microelectrodes. , 2000, Analytical chemistry.

[31]  Adam K Dengler,et al.  Microfabricated Microelectrode Sensor for Measuring Background and Slowly Changing Dopamine Concentrations. , 2013, Journal of electroanalytical chemistry.