用混合植物组织碳糊生物微电极在体测定大鼠纹状体内多巴胺含量

应用混合植物组织碳糊生物微电极在体测定了活大鼠纹状体内多巴胺(DA)含量。该电极灵敏度和选择性良好,检出下限为32.5 n mol/L。抗坏血酸(AA)、肾上腺素(E)、5-羟色胺酸(5-HTP)在此电极上有良好的阳极峰,而且与DA峰完全分离,不干扰DA的测定。5-羟色胺(5-HT)对DA的测定也无明显影响。应用该生物微电极在体动态地观察了给予左旋多巴(L-DOPA)及利血平后活体大鼠纹状体内DA含量的变化,电极稳定性好,在体内可以连续工作10h左右。

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.