一种基于感光干膜-铟锡氧化物电极的简易细胞阻抗传感器实现细胞形态学和阻抗信息同时检测

A Simple Cellular Impedance Biosensor Based on Dry Film Photoresist-Indium Tin Oxide Electrode for Detecting Cellular Morphology and Impedance Information Simultaneously

加工一种基于感光干膜-铟锡氧化物DFP-ITO(Dry Film Photoresist-Indium Tin Oxide)电极的细胞阻抗生物传感器并实现细胞形态学和阻抗信息同时检测。35μm厚的感光干膜层压在ITO导电玻璃表面上作为绝缘层,通过照相制版技术在感光干膜绝缘层上蚀刻不同直径圆孔;以DFP-ITO作为工作电极,通过夹具和测量小池与Ag/Ag Cl参比电极、Pt丝对电极相连构成三电极阻抗测量系统;考察了不同直径DFP-ITO工作电极阻抗谱特征;通过细胞粘附实验及细胞毒性实验考察了感光干膜细胞生物相容性;通过光学显微镜和阻抗谱技术分别对接种在DFP-ITO电极上人肺癌细胞株A549粘附、增殖过程中的形态学和阻抗信息进行检测和分析。研究结果发现不同直径DFP-ITO电极具有相似的阻抗特性;充分固化的感光干膜表面适宜A549细胞粘附且无明显的细胞毒性;基于DFP-ITO电极构建的细胞阻抗传感器能够通过光学显微镜获取A549细胞形态学数据,同时通过阻抗谱技术能够解析A549细胞粘附、增殖过程中的细胞质膜电容、细胞-细胞间隙电阻、细胞-ITO电极间隙电阻变化。本文发展了基于DEP-ITO电极的细胞阻抗传感器结构简单,可实现细胞形态学和阻抗信息的双通道获取,未来可用于细胞生理病理学行为和药物细胞毒性研究。

This study describes the fabrication of a simple cellular impedance biosensor based on dry film Photoresist-indium tin oxide（DFP-ITO） electrode for detecting the cellular morphology and impedance information simultaneously. A dry film photoresist layer of 35 microns thickness was laminated on the surface of the ITO conductive glass as an insulating layer, and then circular holes with different diameters were etched on the insulation layer by photolithography technique. The exposed ITO electrode, as a working electrode, was connected to an Ag/AgCl reference electrode and a Pt counter electrode through a clamp and a measuring pool to constitute a Three-electrode impedance measurement system. The impedance of the DFP-ITO electrodes was investigated by impedance spectroscopy technology. The biocompatibility of the dry film photoresist was investigated by experiments of cell adhesion and cell toxicity. The biological behavior information about cell adhesion and proliferation of the A549 lung cancer on the DFP-ITO electrode was analyzed by optical microscope and impedance spectroscopy technology respectively. Results showed that the DFP-ITO electrodes with different diameters had similar impedance characteristics. Fully cured dry film photoresist could provide an appropriate surface for A549 cell adhesion and had no obvious cytotoxicity. The cellular impedance sensor based on the DFP-ITO electrode could be used to obtain the morphological data and analyze the changes of the cytoplasm membrane capacitance, cell-cell gap resistance and cell-ITO electrode gap resistance during the process of adhesion and proliferation of A549 cell by optical microscope and impedance spectrum technology respectively. The cellular impedance biosensor based on DFP-ITO electrode has a simple structure and can realize the Dual-channel acquisition of cell morphology and impedance information. It can be used in the fields of cellular physiological and pathological behavior and drug cytotoxicity in the future.