基于微电极阵列的自动环境监测电子舌的设计

Design of MEA-based electronic tongue for automatic environmental monitoring

基于电化学微电极阵列,研发了一种用于环境中有毒痕量重金属检测的新型电子舌。系统采用差分脉冲阳极溶出伏安法,分三路实现了溶液中锌、镉、铅、铜、锰和砷6种重金属离子浓度的同时自动检测。每路传感器正面为30×30的硅基底金微电极阵列,背面集成了Ag/AgCl参比电极和Pt对电极。通过PC多线程控制三路恒电位仪电路、蠕动泵和电磁阀,实现自动进样、检测和清洗。一次测量可以在5 min内完成,每路只需要2 mL样品。采用标准加入法进行定量分析,检出限达到10^(-6)g/L级。此电子舌系统具有小体积、低成本等特点,适用于环境水样中重金属浓度分布的现场连续在线测量。

An automatic monitoring electronic tongue based on electrochemical microelectrode array （MEA） was developed for trace heavy metal analysis. Simultaneous detections of trace Zn （Ⅱ）, Cd （Ⅱ）, Pb （Ⅱ）, Cu （Ⅱ）, Mn （Ⅱ） and As （Ⅲ） in water samples were performed with differential pulse anodic stripping voltammetry （DPASV） using three sensors in three channels. Each sensor chip consists of a silicon-based 30 × 30 Au microelectrode array as the working electrode on one side, and an Ag/AgCl reference electrode and a Pt counter electrode on the other side. Using a computer controlled multipotentiostat, several pumps and valves, the electronic tongue realizes in-situ real-time detection of the six metals mentioned above at parts-per-million level without manual operation. One measurement can be completed in 5 rain with only 2 mL sample for each channel.