title: Overoxidation of carbon-fiber microelectrodes enhances dopamine adsorption and increases sensitivity.
abstract: The voltammetric responses of carbon-fiber microelectrodes with a 1.0 V and a 1.4 V anodic limit were compared in this study. Fast-scan cyclic voltammetry was used to characterize the response to dopamine and several other neurochemicals. An increase in the adsorption properties of the carbon fiber leads to an increase in sensitivity of 9 fold in vivo. However the temporal response of the sensor is slower with the more positive anodic limit. Increased electron transfer kinetics also causes a decrease in the relative sensitivity for dopamine vs. other neurochemicals, and a change in their cyclic voltammograms. Stimulated release in the caudate-putamen was pharmacologically characterized in vivo using Ro-04-1284 and pargyline, and was consistent with that expected for dopamine.
authors.affiliation: Department of Chemistry and Neuroscience Center, Chapel Hill, NC 27599, USA.
authors.forename: Michael L A V
authors.initials: ML
authors.lastname: Heien
authors.forename: Paul E M
authors.initials: PE
authors.lastname: Phillips
authors.forename: Garret D
authors.initials: GD
authors.lastname: Stuber
authors.forename: Andrew T
authors.initials: AT
authors.lastname: Seipel
authors.forename: R Mark
authors.initials: RM
authors.lastname: Wightman
mesh_terms: D000818:Animals; D001923:Brain Chemistry; D002244:Carbon; D004298:Dopamine / Q000032:analysis*; D004563:Electrochemistry / Q000379:methods; D008297:Male; D008839:Microelectrodes; D051381:Rats; D017207:Rats, Sprague-Dawley; D012680:Sensitivity and Specificity
chemical_list: D002244:Carbon; D004298:Dopamine