Overoxidized polypyrrole film directed DNA immobilization for construction of electrochemical micro-biosensors and simultaneous determination of serotonin and dopamine
Overoxidized polypyrrole film directed DNA immobilization for construction of electrochemical micro-biosensors and simultaneous determination of serotonin and dopamine
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DOI：
10.1016/j.aca.2005.01.049
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发表时间：
2005-04-29
影响因子：
6.2
通讯作者：
Lin, XQ
中科院分区：
文献类型：
--
作者：
Jiang, XH;Lin, XQ
以过氧化聚吡咯（PPyox）为模板，将小牛胸腺DNA电化学固定于碳纤维电极（CFE）上，制备了一种同时测定5-羟色胺（5-HT）和多巴胺（DA）的电化学微传感器。与简单的PPyox或DNA涂层相比，这种纳米厚度的DNA-PPyox生物复合物修饰层对这些神经元胺表现出上级选择性和灵敏度。该微传感器对5-HT、DA和25,000倍过量的抗坏血酸（AA）在0.38、0.20和-0.02 V处产生三个分离的微分脉冲伏安（DPV）峰。5-HT在1.0 x 10（-8）至1.0 x 10（-6）M范围内获得线性响应，检测限为7.0 x 10（-9）M，在3.0 × 10（-7）至1.0 × 10（-6）M范围内，检测限为（s/n = 3.0）的5.0 × 10（-9）M DA。观察到5-HT与改性层的更强相互作用，该修饰电极对5-HT和DA的检测灵敏度均高于对DA的检测灵敏度，并用于人血清中5-HT和DA的测定。(c)2005 Elsevier B. V.保留所有权利。
A promising electrochemical microsensor was fabricated by electrochemical immobilization of calf-thymus DNA on a carbon fiber electrode (CFE) through an overoxidized polypyrrole (PPyox) template for simultaneous determination of serotonin (5-HT) and dopamine (DA). Such a DNA-PPyox biocomposite modification layer of nano-thickness exhibited superior selectivity and sensitivity towards these neuronal amines comparing with a simple PPyox or DNA coating. This microsensor gave three separated differential pulse voltammetric (DPV) peaks at 0.38, 0.20 and -0.02 V for 5-HT, DA and 25,000-fold excess of ascorbic acid (AA). The linear response was obtained in the range of 1.0 x 10(-8) to 1.0 x 10(-6) M with a detection limit of 7.0 x 10(-9) M for 5-HT, and in the range of 3.0 x 10(-7) to 1.0 x 10(-6) M with a detection limit (s/n = 3.0) of 5.0 x 10(-9) M for DA. A stronger interaction of 5-HT with the modification layer was observed, which led to a higher detection sensitivity for 5-HT than for DA. The utility of this modified electrode was demonstrated by the determination of 5-HT and DA in human blood serum. (c) 2005 Elsevier B.V. All rights reserved.