基于氧化石墨烯/聚吡咯-铟锡氧化物微电极的细胞阻抗生物传感器构建及细胞粘附增殖行为检测

构建一种基于氧化石墨烯/聚吡咯-铟锡氧化物GO/PPy-ITO（Graphene Oxide/Polypyrrole-Indium Tin Oxide）微电极的细胞阻抗生物传感器并用于细胞粘附增殖行为学检测。ITO微电极采用光刻技术对感光干膜绝缘层蚀刻而成，通过一步法电聚合技术在ITO微电极表面沉积GO/PPy纳米复合膜制备GO/PPy-ITO微电极；形状测量激光显微镜和扫描电子显微镜分别对GO/PPy表面粗糙度和拓扑形貌进行表征；电化学循环伏安法及阻抗谱表征GO/PPy-ITO微电极的电化学性质；人肺癌细胞株A549粘附、铺展和增殖实验考察GO/PPy界面的生物相容性；以GO/PPy-ITO微电极作为传感电极，利用电化学阻抗谱技术对A549细胞的粘附增殖行为进行检测。结果显示，ITO微电极表面上电沉积的GO/PPy纳米复合物表面平整，分布大量的微孔结构；电化————————————学实验结果显示GO/PPy-ITO微电极比裸ITO微电极具有更低的阻抗特征和更高的电化学活性；GO/PPy比纯PPy膜更能促进A549细胞粘附、铺展和增殖；GO/PPy-ITO微电极表面A549细胞的粘附增殖行为改变电极系统的阻抗谱特征，通过对阻抗谱数据进行等效电路拟合分析获得细胞粘附增殖行为学信息。本文发展的GO/PPy-ITO微电极兼具优良的电化学性质和细胞生物相容性，基于该电极系统构建的细胞阻抗生物传感器可用于细胞病理生理学行为、药物筛选等研究领域。

Construction of a Cell Impedance Biosensor Based on Graphene oxide /Polypyrrole-Indium Tin Oxide Micro-electrode for Detecting Cell Adhesion and Proliferation

This paper describes a cell impedance biosensor based on graphene oxide/polypyrrole-indium tin oxide(GO/PPy-ITO)microelectrode for detecting cell adhesion and proliferation. The ITO microelectrode was firstly fabricated by etching the insulating layer of photosensitive dry film with lithography technology. Then GO/PPy nanocomposite was deposited on the surface of the ITO microelectrode by one-step electropolymerization to form the GO/PPy-ITO micro?electrode. Shape measuring laser microscope and scanning electron microscope were used to characterize the surface roughness and topology of the GO/PPy respectively. The electrochemical properties of the GO/PPy-ITO microelectrode were measured by cyclic voltammetry and electrochemical impedance spectroscopy. Human lung cancer cells A 549 adhesion,spreading and proliferation experiments were used to characterize the biocompatibility of the GO/PPy. Used the GO/PPy-ITO microelectrode as sensing electrode,A549 cells adhesion and proliferation were detected by electro?chemical impedance spectroscopy. Results showed that the GO/PPy nanocomposite electrodeposited on the surface of the ITO microelectrode had a special structure of smooth surface and abundant micro-pore distribution. Compared with bare ITO microelectrode,GO/PPy-ITO microelectrode had a lower impedance and higher electrochemical activity. Meanwhile,A549 cells cultured on GO/PPy-ITO could attach,spread and proliferate more rapidly than pure PPy. Final?ly,as the adhesion and proliferation of A549 cells on the surface of GO/PPy-ITO microelectrode would change the im?pedance spectrum characteristics of the electrode system,the information on the cell adhesion and proliferation could be obtained by fitting the impedance spectrum data with the equivalent circuit model. Therefore,as the excellent elec?trochemical properties and biocompatibility of the GO/PPy-ITO microelectrode,cell-based impedance biosensor based on this type of microelectrode could be used in the filed such as cellular pathophysiology and drug screening.