Name: gold nanoparticle modified carbon fiber microelectrodes for enhanced neurochemical detection
Uploaded: 2019-05-13T14:45:00
Description: Watch this Scientific Journal Video about Gold Nanoparticle Modified Carbon Fiber Microelectrodes for Enhanced Neurochemical Detection at JoVE.com

我们要感谢美国大学、学院研究支持赠款、美国宇航局DC太空赠款和NSF-MRI+1625977。

1. 碳纤维微电极的建造
<ol><li>
碳纤维的制备
	<ol>
<li>要创建碳纤维微电极,首先使用手、手套和铲子逐一分离碳纤维(碳纤维,直径 7 mm)。</li>
		<li>从扭曲的纱线中拉出或拉一根纤维。</li>
		<li>将分离的碳纤维吸入玻璃毛细管(单桶硼硅酸盐毛细管玻璃,无微丝,外径 1.2 mm,内径 0.68 mm)。</li>
		<li>通过切割一块长约 10 厘米 x 25 厘米宽的纸板,为电极创建电极支架。</li>
	</ol>
</li>
	<li>使用垂直?...

<ol>
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J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Communication&#8212;Carbon+Nanotube+Fiber+Microelectrodes+for+High+Temporal+Measurements+of+Dopamine.">Communication&#8212;Carbon Nanotube Fiber Microelectrodes for High Temporal Measurements of Dopamine.</a> Journal of The Electrochemical Society. 165, G3071-G3073 (2018).</li><li>Park, J., Takmakov, P., Wightman, R. 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G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Carbon+Nanoelectrodes+for+the+Electrochemical+Detection+of+Neurotransmitters.">Carbon Nanoelectrodes for the Electrochemical Detection of Neurotransmitters.</a> International Journal of Electrochemistry. , (2018).</li><li>Kim, J. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dopamine+neurons+derived+from+embryonic+stem+cells+function+in+an+animal+model+of+Parkinson's+disease.">Dopamine neurons derived from embryonic stem cells function in an animal model of Parkinson's disease.</a> Nature. 418, 50 (2002).</li><li>Zestos, A. G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ruboxistaurin+Reduces+Cocaine-Stimulated+Increases+in+Extracellular+Dopamine+by+Modifying+Dopamine-Autoreceptor+Activity.">Ruboxistaurin Reduces Cocaine-Stimulated Increases in Extracellular Dopamine by Modifying Dopamine-Autoreceptor Activity.</a> ACS Chemical Neuroscience. 10, 1960-1969 (2019).</li><li>Zestos, A. G., Kennedy, R. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microdialysis+Coupled+with+LC-MS/MS+for+In+Vivo+Neurochemical+Monitoring.">Microdialysis Coupled with LC-MS/MS for In Vivo Neurochemical Monitoring.</a> The AAPS Journal. 19, 1284-1293 (2017).</li><li>Carpenter, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Direct+and+systemic+administration+of+a+CNS-permeant+tamoxifen+analog+reduces+amphetamine-induced+dopamine+release+and+reinforcing+effects.">Direct and systemic administration of a CNS-permeant tamoxifen analog reduces amphetamine-induced dopamine release and reinforcing effects.</a> Neuropsychopharmacology. 42, 1940 (2017).</li><li>Zestos, A. G., Venton, B. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Carbon+Nanotube-Based+Microelectrodes+for+Enhanced+Neurochemical+Detection.">Carbon Nanotube-Based Microelectrodes for Enhanced Neurochemical Detection.</a> ECS Transactions. 80, 1497-1509 (2017).</li><li>Zachek, M. K., Hermans, A., Wightman, R. M., McCarty, G. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electrochemical+Dopamine+Detection:+Comparing+Gold+and+Carbon+Fiber+Microelectrodes+using+Background+Subtracted+Fast+Scan+Cyclic+Voltammetry.">Electrochemical Dopamine Detection: Comparing Gold and Carbon Fiber Microelectrodes using Background Subtracted Fast Scan Cyclic Voltammetry.</a> J Electroanal Chem (Lausanne Switz). 614, 113-120 (2008).</li><li>Li, J., Xie, H., Chen, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+sensitive+hydrazine+electrochemical+sensor+based+on+electrodeposition+of+gold+nanoparticles+on+choline+film+modified+glassy+carbon+electrode.">A sensitive hydrazine electrochemical sensor based on electrodeposition of gold nanoparticles on choline film modified glassy carbon electrode.</a> Sensors and Actuators B: Chemical. 153, 239-245 (2011).</li><li>Hartings, M. R., Fox, D. M., Miller, A. E., Muratore, K. 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在这项研究中,我们演示了一种利用快速扫描循环伏位测量来检测神经递质(如多巴胺)的金纳米粒子改性碳纤维微电极的新方法。该方法是提高生物分子检测灵敏度的一种高效、绿色、相对廉价的方法。沉积在碳纤维表面的金的厚度可以通过电镀时间和电极液中黄金的浓度加以控制。除更快的电子转移动力学外,金改用碳纤维微电极的电活性表面积明显高于裸电极。与裸露的未改性电极材料相比,它?...

碳纤维微电极(CFMEs)1最好用作生物传感器,用于检测几个关键神经递质2的氧化,包括多巴胺3、去甲肾上腺素4、血清素5、腺苷6、组胺7,和其他人8。碳纤维的生物相容性和尺寸使它们最适合植入,因为与较大的标准电极相比,可减轻组织损伤。9 CME 已知具有有用的电化学特性,并且能够快速测量时使用快速电化学技术,最常见的快速扫描循环伏特测量 (FSCV)10,11。FSCV是一种技术,扫描应用电位快速,并提供特定的循环伏象图的特定分析物12,13。快速扫描产生的大充电电流在碳纤维上稳定,可以背景减去以产生特定的环伏图。
由于其最优的电化学和神经生物学的重要性,多巴胺得到了广泛的研究。儿茶酚胺多巴胺是一种重要的化学信使,在神经系统内的运动、记忆、认知和情绪控制中起着关键作用。多巴胺的过剩或缺乏会导致许多神经和心理干扰;其中包括帕金森病、精神分裂症和成瘾行为。今天,帕金森病仍然是一种普遍的疾病,由于参与多巴胺合成的中脑神经元的退化14。帕金森病的症状包括震颤、运动缓慢、僵硬和保持平衡的问题。另一方面,可卡因15和安非他明16、17等兴奋剂促进了多巴胺的溢出。药物滥用最终取代多巴胺的常规流动,使大脑需要多巴胺过剩,最终导致成瘾行为。
近年来,在神经递质检测18中,一直强调提高电极功能。提高电极灵敏度的最广泛方法是涂覆纤维表面。令人惊讶的是,对金属纳米粒子电极位置对碳纤维的研究有限。黄金等金属纳米粒子,可与其他功能材料一起电沉积在纤维表面20。例如,增加神经递质吸附的电活性表面积。电沉积金属纳米颗粒形成迅速,可纯化,并附着在碳纤维上。电化学对于贵金属纳米粒子的沉积和碳纤维的表面增强仍然具有重要意义,因为它能够控制这些纳米粒子的成核和生长。最后,增加的催化和导电特性,以及改进的大众运输是利用金属纳米粒子进行电分析的其他优势。
美国大学高级实验室序列课程(实验生物化学I和II CHEM 471/671-472/672)是分析、物理和生物化学实验室的组合。第一学期是实验室技术概述。第二学期是一个学生驱动和主导的研究项目21。对于这些项目,学生以前曾研究过生物分子、蛋白质、肽和氨基酸促进合成金纳米粒子22、23的机制。最近的工作侧重于在电极表面上形成金纳米粒子(AuNP)生产,以及评估AuNPs对CFM检测神经递质的能力的影响。在目前的工作中,实验室应用了该技术来证明CFM在检测多巴胺氧化方面的灵敏度是通过AuNP在纤维表面的电镀来增强的。每个裸CFME的特点是在检测多巴胺氧化电流以测量CFME表面多巴胺氧化时,扫描速率、稳定性和多巴胺浓度各不相同。然后,Au3+被电化为 Au 0,同时电沉积到光纤表面作为纳米粒子,然后进行一系列表征实验。经过直接比较,发现AuNP-CFM具有较高的多巴胺检测灵敏度。AuNP通过电极定位均匀涂覆到纤维表面,使电活性表面积更高;从而增加多巴胺在改性电极表面的吸附。这导致更高的多巴胺氧化电流。AuNP-CFME多巴胺氧化和还原峰(+Ep)的潜在分离也较小,表明电子转移动力学更快。这项研究的未来工作包括对裸和AuNP-CFME进行体内测试,以检测多巴胺。

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Dopamine hydrochloride</td>
			<td>Sigma Aldrich</td>
			<td>H8502-5G</td>
			<td></td>
		</tr>
		<tr>
			<td>Phosphate Buffered Saline</td>
			<td>Sigma Aldrich</td>
			<td>P5493-1L</td>
			<td></td>
		</tr>
		<tr>
			<td>Pine WaveNeuro Potentiostat</td>
			<td>Pine Instruments</td>
			<td>NEC-WN-BASIC</td>
			<td>This orders comes in bulk with all other accessories such as headstages, adapters, cords, and other electronics</td>
		</tr>
		<tr>
			<td>Pine Flow Cell and Micromanipulator</td>
			<td>Pine Instruments</td>
			<td>NEC-FLOW-1</td>
			<td>This is also another bulk order including the micromanipulator, flow cell, knobs, tubing, connectors, etc.</td>
		</tr>
		<tr>
			<td>Glass-Capillary</td>
			<td>A-M Systems</td>
			<td>602500</td>
			<td></td>
		</tr>
		<tr>
			<td>T-650 Carbon Fiber</td>
			<td>Goodfellow</td>
			<td>C 005711</td>
			<td></td>
		</tr>
		<tr>
			<td>Epon 828 Epoxy</td>
			<td>Miller-Stephenson</td>
			<td>EPON 828 TDS</td>
			<td></td>
		</tr>
		<tr>
			<td>Diethelynetriamine</td>
			<td>Sigma Aldrich</td>
			<td>D93856-5ML</td>
			<td></td>
		</tr>
		<tr>
			<td>Gold (III) chloride</td>
			<td>Sigma Aldrich</td>
			<td>254169</td>
			<td>Comes as either HAuCl4 or AuCl3</td>
		</tr>
		<tr>
			<td>pH meter</td>
			<td>Fisher</td>
			<td>S90528</td>
			<td></td>
		</tr>
		<tr>
			<td>Farraday Cage</td>
			<td>AMETEK TMC</td>
			<td>81-334-03</td>
			<td></td>
		</tr>
		<tr>
			<td>Syringe Pump</td>
			<td>NEW ERA PUMP</td>
			<td>NE-1000</td>
			<td></td>
		</tr>
		<tr>
			<td>Eppendorf Pipettes and Tips</td>
			<td>Eppendorf</td>
			<td>2231000222</td>
			<td>This is also a bulk order containing multiple pipettes and tips</td>
		</tr>
		<tr>
			<td>10 -1,000 mL beakers</td>
			<td>VWR</td>
			<td>10536-390</td>
			<td></td>
		</tr>
		<tr>
			<td>Carbon fiber</td>
			<td>Goodfellow</td>
			<td>C 005711</td>
			<td></td>
		</tr>
		<tr>
			<td>SEM</td>
			<td>JEOL</td>
			<td>JSM-IT100</td>
			<td></td>
		</tr>
	</tbody>
</table>

gold nanoparticle modified carbon fiber microelectrodes for enhanced neurochemical detection

30多年来,碳纤维微电极(CFMEs)一直是神经递质检测的标准。通常,碳纤维被吸进玻璃毛细血管,拉到细锥体,然后用环氧树脂密封,以创建用于快速扫描循环伏特测量测试的电极材料。不过,使用裸粮和公司有几个限制。首先,碳纤维主要含有基平面碳,其表面积相对较低,灵敏度低于其他纳米材料。此外,石墨碳受其时间分辨率和相对较低的导电性的限制。最后,已知神经化学和大分子在碳电极表面结垢,形成非导电聚合物,阻止进一步的神经递质吸附。在这项研究中,我们用金纳米粒子修改CFME,通过快速扫描循环伏特测量来增强神经化学测试。Au3+是从胶体溶液电镀或浸渍到CFM表面的。由于黄金是一种稳定且相对惰性的金属,是神经化学分析测量的理想电极材料。金纳米粒子改性(AuNP-CFMEs)对多巴胺反应的稳定性超过4小时。此外,AuNP-CFME 表现出比未改性 CFM 更高的灵敏度(循环伏象图的峰值氧化电流)和更快的电子转移动力学(较低 +EP或峰值分离)。AuNP-CFMEs 的发展为在检测的较低限度下检测多巴胺浓度和其他神经化学品的快速变化提供了新型电化学传感器的创建。这项工作在增强神经化学测量方面有着巨大的应用。金纳米粒子改性CFM的产生对于开发新型电极传感器以检测啮齿动物体内的神经递质至关重要,研究药物滥用、抑郁、中风、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺血、缺和其他行为和疾病状态。

在图1中,我们显示了一个原理图,其中FSCV测试用于测量体外神经递质的浓度。图 1显示了应用的多巴胺波形。三角形波形扫描从 -0.4 V 到 1.3 V 在 400 V/s。在图的左侧的第二部分,它显示多巴胺氧化多巴胺-正射奎酮(DOQ),从麻醉剂表面到电极表面的两个电子转移过程。最后,当前与时间图的叠加与颜色图叠加。当前与时间图是多巴胺氧?...

Watch this Scientific Journal Video about Gold Nanoparticle Modified Carbon Fiber Microelectrodes for Enhanced Neurochemical Detection at JoVE.com

Gold Nanoparticle Modified Carbon Fiber Microelectrodes for Enhanced Neurochemical Detection

在这项研究中,我们用金纳米粒子修改碳纤维微电极,以提高神经递质检测的灵敏度。

用于增强神经化学检测的金纳米粒子改性碳纤维微电极

For over 30 years, carbon-fiber microelectrodes (CFMEs) have been the standard for neurotransmitter detection. Generally, carbon fibers are aspirated into ...

该方法之所以重要，是因为它能够进行具有高空间和时间分辨率的神经化学检测，从而有可能增强神经化学检测的体内方法。该技术的主要优点是，它是一种快速、简单、可重复的方法，可提高神经递质检测的灵敏度和时间分辨率。演示这个程序的将是萨努贾·莫哈纳拉杰和宝琳·万嫩伯格，我实验室的研究生。首先，将碳纤维材料分离到单个链中，然后从一根链上拉出一个直径为七微米的碳纤维。将真空管连接到硅酸盐玻璃毛细管，将碳纤维吸入毛细管。然后切割一块10厘米的25厘米的纸板，作为电极支架。将纸巾胶带胶带胶带固定在纸板上作为支撑，然后将毛细管插入电极支架，并小心地将其固定在垂直毛细管拉拔器中。配置毛细管拉拔器，将玻璃毛细管拉到电极材料的细锥度并启动。一旦拉入完成，加热线圈冷却，切断连接管拉电极的碳纤维。小心地从毛细管拉拔器上拆下微电子棒。在立体镜或显微镜的引导下，使用锋利的刀片或手术剪刀将每个电极上凸出的碳纤维修剪到大约 100 到 150 微米的长度。接下来，在25毫升小瓶中，使用棉签将10克环氧树脂与0.2毫升的硬质混合。用丙酮填充另一个小瓶。对于每个电极，将碳纤维尖端浸入环氧树脂中 15 秒，然后浸入丙酮中浸 3 秒钟，以去除多余的环氧树脂。环氧树脂后，环氧电极在125摄氏度的烤箱中固化3小时。接下来，使用微操纵器将碳纤维微电极放在银-银氯化物参考电极中，在0.1摩尔水氯化钾中氯尿酸的0.5毫摩尔溶液中放置碳纤维微电极。将电极连接到电位器，使用碳纤维微电极作为工作电极。以 50 毫伏/秒的速度将电极从 0.2 伏扫描至负 1 伏，进行 10 次循环，以执行电极沉积。优化沉积金涂层的参数至关重要。涂层过多会导致噪音和信号过载，而涂层过少不会增强神经化学检测。在测试之前，在去维化水中准备高氯酸中的多巴胺10毫升库存溶液和约一升pH7.4 PBS缓冲液。将多巴胺库存溶液的一微升移入10毫升缓冲液中，使多巴胺溶液成为大约一微摩尔多巴胺溶液。然后将碳纤维微电极和氯化银银参考电极连接到电位。将碳纤维电极和参考电极固定在流动单元装置的头部阶段，并使用微操纵器将它们降入流动单元。将 60 毫升 PBS 缓冲液放入注射器中。用缓冲液填充流动液，将注射器安装到注射器泵中。以每分钟一毫升的速度开始流液缓冲器通过流动单元。然后配置电位，以负 0.4 伏特扫描至 1.3 伏特，以 10 赫兹和 400 伏特/秒的速度扫描。将波形简要地应用于微电位，观察示波器，并调整增益以防止过载。让微电子在缓冲区中平衡 10 分钟。然后将稀释的多巴胺溶液绘制到注射器中，并连接到流动细胞的注射口。将电位统计上的总运行时间设置为 30 秒。开始记录测量结果，等待10秒，然后将0.2毫升多巴胺溶液注射到流动细胞中。运行完成后，使用高清环电压分析软件处理数据。在执行另一个测试之前，让微电子重新平衡 10 分钟。测试完成后，通过三毫升水和三毫升空气注入缓冲液和注射口三次，清洁流动液。涂层碳纤维用扫描电子显微镜成像。金纳米颗粒涂层的厚度和粒径可由电极沉积时间控制。20分钟的电极沉积产生了一个厚厚的金色涂层与锋利的山脊，而5分钟产生薄均匀的黄金涂层。与未修改的电极相比，金纳米粒子涂层碳纤维微电极的峰值氧化电流和电子转移动力学速度明显较高。金纳米颗粒涂层对电极反应的稳定性没有显著影响，如此处在多巴胺溶液中所证明的。裸极和金纳米粒子涂层电极对扫描速率变化均呈线性响应，金涂层电极的变化幅度要大得多。这表明多巴胺吸收可以通过扫描率得到控制。裸极和金纳米粒子涂层电极在多巴胺浓度为 100 纳米摩尔到 10 微摩尔之间线性响应。在较高浓度下观察到一个无症状曲线，表明多巴胺在电极表面是过饱和的。能够以更快的时间尺度和更高的灵敏度检测神经化学变化将有助于回答神经科学中的复杂问题。该方法在分析化学、代谢组学和环境科学中也有应用。虽然学习起来很容易，但视觉演示对于学习制作、修改和测试微电子模型至关重要。该方法的未来方向包括调整金质和其他涂层的沉积，以考虑厚度、尺寸、形状和形态，以优化特定神经递质的检测。研究人员在尝试这项技术之前，应该练习在显微镜下处理小纤维。此外，神经递质库存溶液应准备在烟罩，因为他们使用1摩尔高氯酸。

Research

JoVE Journal

Chemistry

Transport of Surface-modified Carbon Nanotubes through a Soil Column

表面修饰碳纳米管通过土柱运输

Carbon nanotubes (CNTs) are widely manufactured nanoparticles, which are being utilized in a number of consumer products, such as sporting goods, ...

科研

化学

A Filter-based Surface Enhanced Raman Spectroscopic Assay for Rapid Detection of Chemical Contaminants

基于过滤器的表面增强拉曼光谱检测方法的化学污染物快速检测

We demonstrate a method to fabricate highly sensitive surface-enhanced Raman spectroscopic (SERS) substrates using a filter syringe system that can be ...

Hydroquinone Based Synthesis of Gold Nanorods

金纳米棒基于对苯二酚合成

Gold nanorods are an important kind of nanoparticles characterized by peculiar plasmonic properties. Despite their widespread use in nanotechnology, the ...

Liquid-cell Transmission Electron Microscopy for Tracking Self-assembly of Nanoparticles

用于跟踪纳米粒子自组装的液体细胞透射电子显微镜

Drying a nanoparticle dispersion is a versatile way to create self-assembled structures of nanoparticles, but the mechanism of this process is not fully ...

Extraction of Ramie Fiber in Alkali Hydrogen Peroxide System Supported by Controlled-release Alkali Source

缓释碱源负载碱性过氧化氢体系中苎麻纤维的提取

This protocol demonstrates a method for ramie fiber extraction by scouring raw ramie in an alkali hydrogen peroxide system supported by a ...

Electrochemical Impedance Spectroscopy as a Tool for Electrochemical Rate Constant Estimation

电化学阻抗谱作为电化学速率常数估计的一种工具

Electrochemical impedance spectroscopy (EIS) was used for advanced characterization of organic electroactive compounds along with cyclic voltammetry (CV). ...

Rapid Nanoprobe Signal Enhancement by In Situ Gold Nanoparticle Synthesis

Rapid Nanoprobe Signal Enhancement by In Situ Gold Nanoparticle Synthesis

原位金纳米粒子合成快速 Nanoprobe 信号增强

The use of nanoprobes such as gold, silver, silica or iron-oxide nanoparticles as detection reagents in bioanalytical assays can enable high sensitivity ...

Luminophore Formation in Various Conformations of Bovine Serum Albumin by Binding of Gold(III)

Luminophore Formation in Various Conformations of Bovine Serum Albumin by Binding of GoldIII

结合金 (III.) 对牛血清白蛋白不同构象的 Luminophore 形成

The purpose of the presented protocols is to study the process of Au(III) binding to BSA, yielding conformation change-induced red fluorescence (&#955;em ...

Synthesis of Aptamer-PEI-g-PEG Modified Gold Nanoparticles Loaded with Doxorubicin for Targeted Drug Delivery

合成阿普塔默-PEI-g-PEG改性金纳米粒子装载多索鲁比辛用于靶向药物输送

Due to drug resistance and toxicity in healthy cells, use of doxorubicin (DOX) has been limited in clinical cancer therapy. This protocol describes the ...

Quantitative SERS Detection of Uric Acid via Formation of Precise Plasmonic Nanojunctions within Aggregates of Gold Nanoparticles and Cucurbit[n]uril

Quantitative SERS Detection of Uric Acid via Formation of Precise Plasmonic Nanojunctions within Aggregates of Gold Nanoparticles and Cucurbit[n]uril

通过在金纳米颗粒和葫芦的聚集体中形成精确的等离子体纳米结来定量检测尿酸

This work describes a rapid and highly sensitive method for the quantitative detection of an important biomarker, uric acid (UA), via surface-enhanced ...