On-site detection of heavy metals in agriculture land by a disposable sensor based virtual instrument

摘要

A field-based detection system was designed and implemented for the simultaneous determination of heavy metals in soil samples. The detection principle is based on electrochemical differential pulse anodic stripping voltammetry (DPASV). In order to fulfill the requirements of field screening usage, a fast soil pretreatment process using ultrasonic-assisted extraction was applied. A disposable and integrated sensor, incorporating a three-electrode configuration (working electrode, reference electrode and counter electrode), was fabricated by the screen-printing technology and further modified with Nafion polymer and bismuth film. Coupled with the portable and flexible analysis instrument which was developed by virtual instrument technology, this system was used for trace determination of cadmium and lead content in soil. For accurate qualitative and quantitative analysis of heavy metals, the detection methodology based on the statistical algorithm and chemometrics method was proposed. The results showed that the system was sensitive, reliable and effective, which might hold great promise for its on-site analysis applications. (C) 2016 Elsevier B.V. All rights reserved.