基于电化学传感技术的土壤农药残留检测装置设计

Design of soil pesticide residue detection device based on electrochemical sensing technology

为准确掌控农药对农业环境和作物的污染情况,快速精准的农药残留检测手段是当前的重要需求。以土壤中的啶虫脒残留为对象,提出一种基于电化学生物传感技术的新型检测方法,研究制备适用于检测土壤中啶虫脒残留含量的适体传感器,设计基于电化学传感技术的土壤农药残留检测装置,其功能包括田间土壤的样本采集、预处理及土壤啶虫脒残留含量的现场检测等。重点设计采土机构、搅拌机构和农药残留检测单元等,并对各个机构的关键设计参数进行仿真分析和计算,根据分析结果对土壤采样预处理装置的器件进行选型,确定电气控制系统的控制方案。对研制装置检测性能进行综合试验验证,土壤样本采集试验结果表明:当采集土层深度为0~5 cm时,土壤样本质量相对标准偏差≤2%,柱状土壤样本不会黏附在合金钻头表面。与商用电化学工作站对比试验表明,所测啶虫脒浓度值的平均误差仅为0.7%,验证所研制装置检测的精准性。为农药残留快速检测提供新的检测方法和技术支撑。

In order to know well the pollution of pesticides on agricultural environment and crops,it is an important demand to study the rapid and accurate pesticide residue detection methods at present.In this paper,a new detection method based on electrochemical biosensor technology was proposed for the detection of acetamiprid residues in soil.An aptamer sensor suitable for the detection of acetamiprid residues in soil was developed.A soil pesticide residue detection device based on electrochemical sensing technology was designed.It had the functions of field soil collection,pretreatment,and on-site detection for acetamiprid residue content in soil.Soil sampling mechanisms,mixing mechanisms,and pesticide residue detection units were designed.The key design parameters of each mechanism were simulated and calculated.According to the analysis results,the devices of the soil sampling pretreatment device were selected,and the control scheme of the electrical control system was determined.Experimental verification was conducted on the detection performance of the developed device.The results of soil sample collection experiments showed that when the depth of the soil layer was 0-5 cm,the relative standard deviation of soil sample quality was less than 2%,and the columnar soil sample would not adhere to the surface of the alloy drill bit.Compared with commercial electrochemical workstations,the average error of the measured concentration of acetamiprid was only 0.7%,verifying the accuracy of the developed device detection.This study provides new detection methods and technical support for rapid detection of pesticide residues.