Patternable Nanowire Sensors for Electrochemical Recording of Dopamine

Department of Chemical and Biomolecular Engineering, School of Medicine, Johns Hopkins University, Baltimore, Maryland, USA.
Analytical Chemistry (Impact Factor: 5.64). 11/2009; 81(24):9979-84. DOI: 10.1021/ac901744s
Source: PubMed


Spatially resolved electrochemical recording of neurochemicals is difficult due to the challenges associated with producing nanometer-scale patternable and integrated sensors. We describe the lithographic fabrication and characterization of patternable gold (Au) nanowire (NW) based sensors for the electrochemical recording of dopamine (DA). We demonstrate a straightforward NW-size-independent approach to align contact pads to NWs. Sensors, with NW widths as small as 30 nm, exhibited considerable insensitivity to scan rates during cyclic voltammetry, a nonlinear increase in oxidation current with increasing NW width, and the selectivity to measure submaximal synaptic concentrations of DA in the presence of interfering ascorbic acid. The electrochemical sensitivity of Au NW electrode sensors was much larger than that of Au thin-film electrodes. In chronoamperometric measurements, the NW sensors were found to be sensitive for submicromolar concentration of DA. Hence, the patternable NW sensors represent an attractive platform for electrochemical sensing and recording.

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Available from: Pawan Tyagi, May 04, 2015
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    • "Several components of a TJMD, electrodes and molecules in the exposed regions, can interact with one or more chemicals or biochemicals [108]. Utilization of Au as one of the metal electrode may enable a TJMD to do electrochemistry based neurochemical sensing [109]. Utilization of molecule as sensing element can be used to target the miniscule amounts of hazardous molecules. "
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