CHARACTERIZATION OF AMPEROMETRY FOR IN-VIVO MEASUREMENT OF DOPAMINE DYNAMICS IN THE RAT-BRAIN
CHARACTERIZATION OF AMPEROMETRY FOR IN-VIVO MEASUREMENT OF DOPAMINE DYNAMICS IN THE RAT-BRAIN
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DOI：
10.1016/0039-9140(94)e0064-x
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发表时间：
1994-06-01
期刊：
影响因子：
6.1
通讯作者：
WIGHTMAN, RM
中科院分区：
文献类型：
--
作者：
KAWAGOE, KT;WIGHTMAN, RM
恒电位安培法与Nafion涂层的碳纤维电极已被评估为在体内检测的神经递质多巴胺的技术。并对该技术的结果进行了比较 与在神经元电刺激期间多巴胺释放到脑细胞外空间期间在同一电极上用快速扫描循环伏安法获得的结果有关。数据表明，恒电位安培法是一种可行的技术，用于检测低浓度的多巴胺。多巴胺渗透膜更快地与恒电位安培法比重复快速扫描循环伏安法预测的扩散方程。对于循环伏安法的情况下，它表明，通过Nafion膜的扩散所造成的时间延迟，可以通过去卷积程序。尽管恒电位安培法作为体内监测技术的适用性，但与快速扫描循环伏安法相比，它确实有几个缺点。扩散层延伸到Nafion膜之外，使得基于体外校准的浓度测定更难以解释。报道的浓度大于通过循环伏安法获得的浓度，循环伏安法是一种扩散层限于Nafion膜的技术，并且该结果可能低估了多巴胺和抗坏血酸的邻醌之间的催化反应的效果。发现安培法仅提供比循环伏安法稍微改进的信噪比，尽管使用更大的滤波。这是因为多巴胺在膜中积累的优势丧失了。此外，安培信号的小幅度使其更容易受到电干扰。
Constant potential amperometry with Nafion-coated carbon-fiber electrodes has been evaluated as a technique for in vivo detection of the neurotransmitter dopamine. The results of this technique have been compared to results obtained with fast-scan cyclic voltammetry at the same electrode during release of dopamine into the extracellular space of the brain during electrical stimulation of neurons. The data indicate that constant potential amperometry is a viable technique for detecting low concentrations of dopamine. Dopamine permeates the film more quickly with constant-potential amperometry than with repeated fast-scan cyclic voltammetry as predicted by diffusion equations. For the case of cyclic voltammetry, it is demonstrated that the temporal delay caused by diffusion through Nafion film can be removed by deconvolution procedures. Despite the suitability of constant potential amperometry as an in vivo monitoring technique, it does have several disadvantages when compared to fast-scan cyclic voltammetry. The diffusion layer extends outside of the Nafion film making determination of concentration based on in vitro calibrations more difficult to interpret. The reported concentrations are larger than obtained by cyclic voltammetry, a technique with the diffusion layer restricted to the Nafion film, and this result is likely an underestimation of the effect of the catalytic reaction between the o-quinone of dopamine and ascorbate. Amperometry was found to provide only slightly improved signal-to-noise ratios than cyclic voltammetry despite the use of greater filtering. This was because the advantage of dopamine accumulation in the film was lost. In addition, the small magnitude of the amperometric signal makes it more susceptible to electrical interference.