Development and characterization of a voltammetric carbon-fiber microelectrode pH sensor.
Development and characterization of a voltammetric carbon-fiber microelectrode pH sensor.
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DOI：
10.1021/la100134r
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发表时间：
2010-06-15
期刊：
影响因子：
--
通讯作者：
Heien ML
中科院分区：
文献类型：
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作者：
Makos MA;Omiatek DM;Ewing AG;Heien ML
本工作描述了一种能够实时测量生物微环境中生理性pH变化的改进型碳纤维微电极传感器的研制和表征。无试剂传感器是在环境条件下，将重氮盐固蓝RR还原到碳纤维表面，在非质子化介质中制备的。用快速扫描循环伏安法研究了表面结合分子中对苯二酚部分的氧化还原活性与pH的关系。传感器在pH 6.5-8.0的溶液中进行体外校准，得到了依赖于pH的阳极峰电位响应。用流动注射分析对修饰后的微电极进行了表征，结果表明，修饰后的微电极对0.005个pH单位的酸碱变化敏感。此外，该修饰电极被用来测量微分析模型果蝇中枢神经系统神经递质释放过程中体内pH的动态变化。
This work describes the development and characterization of a modified carbon-fiber microelectrode sensor capable of measuring real-time physiological pH changes in biological microenvironments. The reagentless sensor was fabricated under ambient conditions from voltammetric reduction of the diazonium salt Fast Blue RR onto a carbon-fiber surface in aprotic media. Fast-scan cyclic voltammetry was used to probe redox activity of the p-quinone moiety of the surface-bound molecule as a function of pH. In vitro calibration of the sensor in solutions ranging from pH 6.5 to 8.0 resulted in a pH-dependent anodic peak potential response. Flow-injection analysis was used to characterize the modified microelectrode, revealing sensitivity to acidic and basic changes discernable to 0.005 pH units. Furthermore, the modified electrode was used to measure dynamic in vivo pH changes evoked during neurotransmitter release in the central nervous system of the microanalytical model organism Drosophila melanogaster.