Zhao He, Markow Owen, Olaitan Greatness, Donarski Eric D, Lester Kevin C, Lavrik Nickolay V, Venton B Jill
Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States.
Center for Nanophase Materials Sciences, Oak Ridge National Lab, Oak Ridge, Tennessee 37831, United States.
ACS Electrochem. 2025 Mar 27;1(5):730-740. doi: 10.1021/acselectrochem.4c00180. eCollection 2025 May 1.
Carbon electrodes are typically used for dopamine detection, and new types of electrodes and customized fabrication methods will facilitate new applications. Parylene is an insulator that can be deposited in a thin layer on a substrate and then pyrolyzed to carbon to enable its use as an electrode. However, pyrolyzed parylene has not been used for the real-time detection of neurochemicals by fast-scan cyclic voltammetry. In this work, we deposited thin layers of parylene-N (PN) on metal wires and then pyrolyzed them to carbon with high temperatures in a rapid thermal processor (RTP). Different masses of PN, 1, 6, and 12 g, were deposited to vary the thickness. RTP-PN (6 g) produced a 194 nm layer carbon thickness and had optimal electrochemical stability. Pyrolyzed parylene-N modified electrodes (PPNMEs) were characterized for electrochemical detection of dopamine, serotonin, and adenosine. Background-normalized currents at PPNMEs were about 2 times larger than those of carbon-fiber microelectrodes (CFMEs). Rich defect sites and oxygen functional groups promoted the neurochemical adsorption of cationic neurotransmitters. PPNMEs resisted fouling from serotonin polymer formation. PPNMEs were used to detect stimulated dopamine release and monitor spontaneous adenosine release. Pyrolyzed parylene is a sensitive and fouling-resistant thin-film carbon electrode that could be used in the future for making customized electrodes and devices.
碳电极通常用于多巴胺检测，新型电极和定制制造方法将推动新的应用。聚对二甲苯是一种绝缘体，可以以薄层形式沉积在基板上，然后热解成碳以用作电极。然而，热解聚对二甲苯尚未用于通过快速扫描循环伏安法实时检测神经化学物质。在这项工作中，我们将聚对二甲苯-N（PN）薄层沉积在金属丝上，然后在快速热处理器（RTP）中高温热解成碳。沉积不同质量的PN，1、6和12克，以改变厚度。RTP-PN（6克）产生了194纳米厚的碳层，具有最佳的电化学稳定性。对热解聚对二甲苯-N修饰电极（PPNMEs）进行了表征，用于多巴胺、血清素和腺苷的电化学检测。PPNMEs的背景归一化电流约为碳纤维微电极（CFMEs）的2倍。丰富的缺陷位点和氧官能团促进了阳离子神经递质的神经化学吸附。PPNMEs可抵抗血清素聚合物形成造成的污染。PPNMEs用于检测刺激的多巴胺释放并监测自发的腺苷释放。热解聚对二甲苯是一种灵敏且抗污染的薄膜碳电极，未来可用于制造定制电极和设备。
