基于微流控纸芯片的持久性有机氯农药残留光致电化学检测

In this project, photoelectrochemical method was introduced into microfluidic paper-based device to establish a low-cost, simple and sensitive two-dimensional (2D) microfluidic paper-based photoelectrochemical device for pesticide residue. It aims at developing a fast, on-line and real-time determination of persistent organochlorine pesticide residue. A self-powered microfluidic paper-based photoelectrochemical device was fabricated by utilizing the light source of the photoelectrochemical method to provide the bias potential for signal amplification. This self-powered microfluidic paper-based photoelectrochemical device could further simplify the external equipments, reduce the detection limit and enhance its detectability. Semiconductor imprinted polymer, possessing high molecular recognition ability and photoelectrochemical activity, was introduced into this novel microfluidic paper-based photoelectrochemical device to enhance the specificity of this paper-based device. Due to the complexity and diversity of pesticide residue, 3D microfluidic paper-based photoelectrochemical device was demonstrated to develop high-throughput and multi-functional microfluidic paper-based photoelectrochemical device. The high throughput detection and quantity production of this 3D microfluidic paper-based photoelectrochemical device were investigated. In addition, the portable light-current detector was improved to match the 3D microfluidic paper-based photoelectrochemical device through a home-made device holder. Finally, the preliminary technological theory and technological base of low-cost, fast, on-line and real-time determination of pesticide residue were establish based on 3D microfluidic paper-based photoelectrochemical device.

针对目前对残留的持久性有机氯农药实现现场、即时和快速分析的需求，本项目在纸芯片上引入光致电化学分析方法，制备成本低、操作简单、灵敏度高的二维微流控光致电化学有机氯农残检测纸芯片；设计制备微流控纸芯片光电自供能系统，借助光致电化学的激发光源，为纸芯片提供光致电化学的检测偏压，实现信号放大，简化检测装置，提高检测灵敏度和检测能力；合成引入纳米半导体分子印迹聚合物，发展兼有分子特异性识别和光致电化学活性的人工抗体半导体分子印迹聚合物，开发构建高选择性分子识别光致电化学微流控纸芯片，提高有机氯农残样品的现场快速特异性检测能力；针对农残的多样性与复杂性，进一步开发三维高通量农残检测的光致电化学微流控纸芯片，探索高度集成化三维纸芯片的农残批量检测模式与纸芯片的批量制备工艺；改进手持电流检测设备的显示与操作界面并设计制作匹配的纸芯片夹，初步建立低成本的现场、即时、快速简便农残分析技术理论与技术基础。

在本项目中，围绕目前对残留的持久性有机氯农药实现现场、即时和快速分析的需求，设计并优化了微流控纸芯片中亲水微通道的形状、位置、分布等参数；对微流控纸芯片的亲、疏水通道的形貌及其亲疏水性能等进行了表征；构建了基于微流控纸芯片的丝网印刷三电极体系；采用原位生长法制备了贵金属、双金属等纳米材料修饰的高性能的纸电极；引入电化学发光、光致电化学等分析方法；研究了纸芯片上电子传输机制与影响因素，提出了相应的纸上免疫光致电化学方法的检测机理；制备了多种光致电化学性能优良的纳米材料及其复合材料，结合吸收光谱、电化学、电致化学发光、光致电等分析方法，对半导体纳米材料的应用机理进行合理推测；多种纳米材料的应用增强电子的传输能力，放大传输的电子信号，实现高灵敏的光致电化学的检测；研究纸芯片内置光源及其光源强度与性能匹配，实现纸芯片上免光源的光致电化学检测分析；探索了纸芯片自供能的方式方法，为实现纸芯片的现场即时检测奠定理论与技术支持；针对被测物制备相应的半导体分子印迹聚合物，并进行纳米半导体印迹/非印迹聚合物的LUMO与HOMO轨道能带隙进行测定，计算LUMO能级位置，并与量子化学模拟计算结果比对；组建与应用三维集成（阵列式/混合式）功能纸芯片；对实际样品进行测定并与业化检测方法进行了比对；设计制作纸芯片夹，为功能集成纸芯片的应用推广奠定了基础。