The development of linear sweep voltammetry with carbon paste electrodes in vivo

A number of advances have been made in the application of linear sweep voltammetry with carbon paste electrodes to the monitoring of ascorbate and monoamine neuroregulator metabolites in the brain of the freely-moving rat. These new measures are: the reduction of the sweep rate of 5 mV/s; the elimination of semidifferentiation in chronic recordings; the measurement in situ and subtraction of the background current for each electrode; the reduction, to practically zero levels, of the ascorbate signal in alternate scans; and corrections for circadian changes. These innovations enable one to monitor changes in the monoamine metabolites, even when there are simultaneous, large changes in ascorbate.