固/液界面修饰调控有机电化学晶体管响应特性及生物传感研究

Besides the device physical characteristics, the other key factors that determine the performances of the organic electrochemical transistors (OECTs)-based biosensors are the solid/liquid interface modifications, including interface charge transfer, electrochemical activity and immobilization of recognition biomolecules and so on. In this project, combining the specialties of the noble metal nanoparticles and their carbon nanomaterial hybrids (large specific surface area, excellent electrochemical activity and biocompatibility, etc) and the advantages of OECTs such as sensitive signal transforming/amplifying effects, the gate/electrolyte and conjugated polymer film/electrolyte interfaces of the OECT devices are modified with nanomaterials and the recognition biomolecules by super-molecular assembly to construct OECTs-based biosensors, which will apply in the detections of enzyme substrates, nucleic acid targets, mircoRNAs, and tumor marker related antigens/antibodies. The adjusting and controlling of OECT response characteristics by solid/liquid interface modification are investigated in detail by various analytical methods. The effects of the parameters for OECTs preparation and solid/liquid interface modifications by nanomaterials on the performances of OECTs-based biosensors are intensively studied. Through the development of this project, it hopes to obtain new understandings and points at the mechanism and effect factors that will adjust and control the OECTs-based biosensors; at the same time, it is hopeful to construct and develop OECTs-based biosensors with high performances and the potentials to apply to commercial applications.

有机电化学晶体管（OECTs）生物传感器性能除受器件物理性能制约外，另一决定因素即固/液界面修饰，这包括界面电荷传输、电化学反应活性和生物识别分子固载等。本项目拟将贵金属纳米粒子及其碳纳米材料杂化物的特点（大比表面积、优异的电化学活性和生物亲和性等）与OECTs的优点（灵敏的信号转换/放大作用）相结合，采用超分子组装对OECTs栅极/电解质、有机共轭聚合物薄膜/电解质界面进行纳米材料修饰和生物识别分子固定，构建OECTs生物传感器，用于酶、核酸识别物、小分子RNA和肿瘤标志物相关抗原/抗体生物传感检测。采用多种分析测试方法详细研究固/液界面修饰对OECTs响应特性的调控；深入探讨OECTs制备参数和固/液界面纳米材料修饰对其生物传感性能的影响。以期在OECTs生物传感器调控原理、影响因素等方面获得新的理解和观点；同时开发高性能、具有商业应用前景的OECTs生物传感器。

本研究利用丝网印刷技术和旋转涂膜技术制备了柔性有机电化学晶体管（OECTs）器件，优化了器件制备参数（包括丝网印刷网板设计、源-漏极长度和旋转涂膜速度等）；采用界面化学还原等方法制备了贵金属纳米粒子（金和铂纳米粒子等）和碳纳米材料（碳纳米管、石墨烯）-贵金属纳米粒子杂化物；通过组装、化学交连等技术将纳米材料和生物识别分子修饰至电极界面，构建了基于OECTs的多种生物传感器。结果表明：所制备OECTs器件具有调控灵敏、稳定性好等特点；且制备技术具有步骤简单、成本低、可批量生产等特点；通过优化合成条件，可获得小粒径、尺寸可控、具有高分散性能的贵金属纳米粒子及其碳纳米材料杂化物。将此种纳米材料修饰至电极界面可极大提高电极的电化学反应活性和OECTs器件调控灵敏性；并有利于生物识别分子的固定。基于纳米材料界面修饰和OECTs构建的小分子RNA、细胞等生物传感器具有灵敏度高、选择性好等优点；并具有好的实际样品检测性能。项目的研究结果对于理解OECTs生物传感器调控原理、影响因素等方面具有重要理论意义；在开发低成本、高性能、具有商业应用前景OECTs生物传感器方面具有实际应用前景。