Carbon nanotube fiber and yarn microelectrodes for high temporal resolution measu

用于高时间分辨率测量的碳纳米管纤维和纱线微电极

• 批准号: 8701642
• 负责人: B. JILL VENTON
• 金额: $ 18.88万
• 依托单位: UNIVERSITY OF VIRGINIA
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-04-01 至 2016-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8701642
• 关键词: Action Potentials; Adenosine; Adsorption; Affect; Ascorbic Acid; Behavior; Behavior Control; Biological; Brain; Carbon Nanotubes; Characteristics; Chemicals; Coagulants; Data; Detection; Disease; Disease model; Dopamine; Drug Addiction; Electrodes; Fiber; Fingerprint; Fire - disasters; Future; Goals; Histamine; Hydrogen Peroxide; Knowledge; Lead; Measurement; Measures; Methods; Microelectrodes; Mission; Monitor; Nature; Neuromodulator; Neurotransmitters; Norepinephrine; Organism; Outcome; Oxides; Physiologic pulse; Polyethyleneimine; Polymers; Property; Public Health; Regulation; Research; Resolution; Sampling; Scanning; Serotonin; Signal Transduction; Surface; Surface Properties; Techniques; Testing; Time; Work; addiction; base; burden of illness; carbon fiber; chemical kinetics; dopaminergic neuron; drug of abuse; improved; in vivo; instrumentation; millisecond; multi walled carbon nanotube; nervous system disorder; neurotransmission; neurotransmitter release; new technology; public health relevance; research study; sensor

DESCRIPTION (provided by applicant): Real-time measurements of neurotransmitters are critical for understanding how chemical signaling is controlled in the brain and how it malfunctions during neurological diseases. Regulation of neurotransmission occurs on a millisecond time scale but monitoring neurotransmitter concentrations has been instrumentally limited to the second to minute time scale. Neurotransmitter measurements require both high temporal resolution and high sensitivity, as nanomolar concentration changes are expected. The goal of this research is to develop high sensitivity, high temporal resolution electrochemical sensors to understand the regulation of dopamine concentrations on a millisecond time scale. The strategy is to fabricate high sensitivity carbon nanotube (CNT) yarn and CNT fiber microelectrodes for high temporal resolution measurements with fast-scan cyclic voltammetry (FSCV). FSCV provides both a fingerprint for identification of the species being detected and high temporal resolution. However, the scan is usually repeated at 100 ms intervals with traditional carbon-fiber microelectrodes because sensitivity decreases with increasing repetition rate. Preliminary data show that CNT yarn and CNT fiber microelectrodes do not suffer from this drawback and can be used with rapid repetition rates. The CNT microelectrodes are expected to provide a 1 nM limit of detection with 2 ms temporal resolution, which is sufficient to characterize dopamine release after single stimulation pulses in vivo for the first time. The firs aim is to study CNT fibers as microelectrode materials. The fibers are made by wet spinning techniques, by extruding CNTs into a coagulant such as polyethyleneimine. The second aim is to test CNT yarns as microelectrode sensors. CNT yarns are a commercial material that is made by twisting aligned CNT arrays into aligned CNT yarns. For both CNT yarn and CNT fiber microelectrodes, the effects of oxide functionalization on adsorption and electrochemical properties will be studied. The best sensors will be used to characterize dopamine release in vivo to show that they are useful for high temporal resolution measurements in a biological sample. The ability to measure release from a single stimulation pulse will enable the hypothesis that the interval between single stimulations during burst firing regulates the amount of dopamine release to be tested. This work is significant because it will overcome a critical instrumentation barrier for monitoring dopamine release and allow the first characterization of dopamine on the millisecond time scale, 50-times faster than currently possible. This will open the door for future studies of how millisecond regulation of dopamine impacts diseases, such as addiction. These sensors could also be implemented to monitor other electroactive compounds including adenosine, serotonin, norepinephrine, histamine, ascorbic acid, and hydrogen peroxide. Thus, the potential impact is a better understanding of the millisecond regulation of many neurotransmitters and neuromodulators.

描述（由申请人提供）：神经递质的实时测量对于理解大脑中的化学信号是如何控制的以及它在神经系统疾病中是如何发生故障的至关重要。神经传递的调节发生在毫秒的时间尺度上，但监测神经递质浓度的仪器限制在秒到分钟的时间尺度上。神经递质测量需要高时间分辨率和高灵敏度，因为纳摩尔浓度的变化是预期的。本研究的目标是开发高灵敏度，高时间分辨率的电化学传感器，以了解在毫秒时间尺度上多巴胺浓度的调节。该策略是制作高灵敏度碳纳米管（CNT）纱线和碳纳米管纤维微电极，用于快速扫描循环伏安法（FSCV）的高时间分辨率测量。FSCV为识别被检测物种提供了指纹和高时间分辨率。然而，传统的碳纤维微电极通常每隔100毫秒重复一次扫描，因为随着重复频率的增加，灵敏度会降低。初步数据表明，碳纳米管纱线和碳纳米管纤维微电极没有这个缺点，可以快速重复使用。碳纳米管微电极有望提供1 nM的检测极限和2 ms的时间分辨率，这足以