[Measurement of dopamine in rat striatum in vivo with a biomicroelectrode made from mixed plant tissue-carbon paste]

The mixed plant tissue-carbon paste electrode was prepared and their electrochemical characteristics were investigated. The sensitivity and selectivity of this bioelectrode were found to be good because of the utility in biocatalysis. It may work continuously with high stability for 10 h in vivo. The principal advantages of the new bioelectrodes are shorter in response time and longer in stability. These advantages meet the requirements of in vivo determination. Using these electrodes, the dopamine contents in rat striatum were measured by anodic stripping voltammetry. The drug-induced changes in dopamine levels were monitored. From the results, we can conclude that the biomicroelectrode is a very economic biosensor for its low cost and easiness to prepare and is a valuable tool for studying dopamine function. It will provide a good method for the evaluation of drug actions on dopamine neurones.