Nafion/胆碱双层膜碳纤维电极探测小白鼠大脑内的多巴胺  

A Nafion and Choline Bi-layer Modified Carbon Fiber Electrode for In-vivo Detection of Dopamine in Mouse Cerebrum

作　　者：林祥钦[1] 康广凤[1] 柴颖[1] 

机构地区：[1]中国科学技术大学化学系,合肥230026

出　　处：《分析化学》2008年第2期157-161,共5页Chinese Journal of Analytical Chemistry

基　　金：国家自然科学基金(No.20575062);高等教育博士点专项基金(No.20040358021)

摘　　要：制备了胆碱（Ch）共价键植的碳纤维电极（Ch／CFE），进而吸附涂敷一薄层Nation膜得到了Nation／Ch／CFE。以循环伏安（CV）法和差分脉冲伏安（DPV）法研究了该电极上多巴胺（DA）的电化学响应。使用DPV法，该电极能良好抵抗代谢产物3，4-二羟苯乙酸（DOPAC）和抗坏血酸（AA）的干扰而选择性测量DA。在1．0mmol／LAA存在下，使用5mm长Nafion／Ch／CFE测定DA，检出限（S／N=3）为0．1μmol／L；线性范围为0．4—16μmol／L。该电极适于活体监测。将该电极插入小白鼠大脑纹状体内，实时监测了神经递质DA的浓度及其变化，观察到DA水平由静脉注射药物左旋多巴（L-DOPA）后随时间的响应，并发现针刺激对应于中医“风府穴”的头部皮下组织可引起脑内DA的即时性脉冲释放。Consisting of a choline （Ch） covalently grafted fiber electrode and a thin layer of Nation was prepard and the Nafion/Ch/CFE was obtained. Electrochemical behavior of dopamine （DA） on this prepared electrode was studied by cyclic vohammetry （CV） and differential pulse vohammetry （DPV）. For DPV determination, the electrode can be selectively used to determine DA without interference from dihydroxyphenyl-acetic acid （DOPAC） and ascorbic acid （AA）. In the presence of 1.0 mmol/L AA, a linear range of 0. 4 - 16 μmol/L with a detection limit （ S/N= 3 ） of 0. 1 μmol/L DA was obtained with the electrode of 5 mm column length. The electrode was applied to the in-vivo detection of DA in the striaum area of cerebrum of living mouses. The variation of DA level after a mainline of L-DA was recorded. Prompt pulse releasing of DA for acupuncturing at ＂Fengfu＂ site of the skull was observed. The advantage of the electrode was attributed to the composite structure of negatively charged Nation and positively charged Ch modified layers.

关 键 词：碳纤维电极 表面种植 胆碱 多巴胺 活体监测 化学修饰电极 

分 类 号：R741[医药卫生—神经病学与精神病学]