Development Of A Portable Electrochemical Detection System

Recently, our country’s economy developed fast and violent, resulting in increasingly severe environment pollution. Excessive mining, sewage irrigation, coal emissions, car exhaust and other human activities aggravated heavy metal pollution. Heavy metal can be gathering in organisms and it is difficult to degrade, eventually humans would be harmed after heavy metal entered the food chain, so it is essential to develop the swift detection technology for heavy metal. The electrochemical method has the merit of precise, quick and sensitive in heavy metal measurement, the powerful function and small size of embedded system make portability possible, so in this paper a simple electrochemical test system with DSP is exploited, it can be used in many fields such as environmental protection, biological medicine, medical inspection, chemical research and so on.According to the function demand and technical indicators, a round of software and hardware solutions is offered. On the circuit, design of circuit schematic and PCB layout is finished, in addition the hardware is tested by means of oscilloscope and wave generator; on the program, the underlying embedded program and PC program are accomplished, and various filtering algorithm for electrochemical signals is discussed in detail. Eventually the simple electrochemical experiments with K3Fe(CN)6 indicate the system works well.Firstly, the present status of heavy metal pollution is introduced in the paper, then the electrochemical methods is chose to measure heavy metal content, but foreign instrument is costly. Secondly, the overall solution is put forward according to the basic law of electrochemistry, including circuit and program, the circuit is made up of potentiostat, power supply circuit, DSP minimum system, tiny current measure circuit and so on; the program mainly includes embedded control software and PC interface software. Thirdly, simulation and practical test was done, the CV、SWV and ASV scanning to resistor and K3Fe(CN)6 verified the system’s stability and availability. Finally, a system on LabVIEW is further explored.