DEVELOPMENT OF SELF REFERENCING ELECTROCHEMICAL MICROSENSORS ASCORBIC ACID

自参考电化学抗坏血酸微型传感器的研制

• 批准号: 6120170
• 负责人: D M PORTERFIELD
• 金额: $ 1.87万
• 依托单位: MARINE BIOLOGICAL LABORATORY
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-12-01 至 2000-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6120170
• 关键词: bioengineering /biomedical engineering; biomedical equipment development; biomedical resource; building /facility design /renovation; technology /technique

Experience with both oxygen and nitric oxide measurement using self-referencing probes, and, in particular, the ability to build our own carbon based microsensors has opened up new horizons for molecular flux detection. The detection of ascorbic acid was explored on the request of Harold Behrman (B00. of Obs. and Gyn. Yale Medical School). Ascorbic acid has the curious quality of exhibiting pronounced extracellular flux patterns, with slow oscillations over extended time periods. This is particularly evident in the mammalian CNS where AA electrochemical signals need to be filtered out for catecholamine detection. Our intention in this sub-project was to explore our ability to produce a self-referencing system able to measure single cell flux and thus contribute to our understanding of the underlying AA transport physiology. These probes are built upon the basic carbon fiber electrode used for the construction of the nitric oxide probes and are modified electrochemically to improve sensitivity for ascorbic acid. This preparation involved the electrochemical treatment of a carbon fiber (1.5V for 3 sec; 70 Hz 3V triangle wave with 1.5V offset for 10 sec; followed by a hold at 0V for 30 minutes). This results in a decrease in the working potential required to oxidize AA from 0.9V to 0.05V. The electrodes are calibrated in solutions of known AA concentrations (linear calibration). While the operation of these microprobes in the self-referencing mode has been verified using an artificial gradient, we have not yet applied them to a biological system. Continued development of the self-referencing electrochemical microsensors can occur through three approaches. These include the development of new sensors, the application of cyclic voltammetry and chronoamperometry, but the most rapid approach is the adaptation of existing electrochemical probes for single cell use. An example of the later approach is the new self-referencing ascorbic acid probe whose development was rapid and simpler than moving from oxygen to NO. We anticipate being in a position to over biomedical researchers a "menu" of probes from which they can choose in designing their experiments.

氧和一氧化氮测量的经验， 自我参照探针，特别是，建立我们的能力， 我们自己的碳基微传感器为分子生物学开辟了新的视野。 通量检测 对抗坏血酸的检测方法进行了探讨， 哈罗德·贝尔曼（Harold Behrman）（B00） 妇产科耶鲁医 学校）。 抗坏血酸有一种奇特的特性， 明显的细胞外通量模式，随着时间的推移， 延长的时间段。 这在哺乳动物中尤其明显。 CNS，其中AA电化学信号需要被滤除， 儿茶酚胺检测 我们在这个子项目中的意图是 探索我们创造自我参照系统的能力， 测量单细胞通量，从而有助于我们了解 潜在的AA运输生理学。 这些探测器是建立在 用于构建的基本碳纤维电极 一氧化氮探针和电化学修饰，以改善 抗坏血酸敏感性。 这项准备工作涉及到 碳纤维的电化学处理（1.5V持续3秒; 70Hz 3V 偏移1.5V的三角波持续10秒;然后保持在0V 30分钟）。 这导致工作电位降低 需要将AA从0.9V氧化到0.05V。 电极 在已知AA浓度的溶液中校准（线性 校准）。 虽然这些微探针在微生物系统中的操作 自参考模式已经使用人工梯度进行了验证， 我们还没有将它们应用到生物系统中。 继续 自参考电化学微传感器的发展可以 通过三种方式发生。 其中包括开发新的 传感器，循环伏安法和计时电流法的应用， 但最快的方法是调整现有的 电化学探针用于单电池使用。 以后者为例 方法是新的自参考抗坏血酸探针， 发展是快速和简单的比从氧气到NO。我们 预计将在一个位置，以超过生物医学研究人员的"菜单" 在设计实验时可以从中选择。