Simultaneous Determination of Zn(II), Cu(II), Cd(II) and Pb(II) in Soil Samples Employing an Array of Potentiometric Sensors and an Artificial Neural Network Model

A sensor array of 9 potentiometric PVC sensors has been employed for the simultaneous determination of heavy metals in soil. Sensors were firstly characterized in their response: Nernstian behavior, a concentration range from ca. 10-6 to 10-2 M and selectivity coefficients confirming that all sensors had cross-response for the target ions. The mixed response system was modeled employing Artificial Neural Networks. The proposed tool was applied to the determination of Pb2+, Cd2+, Cu2+ and Zn2+ in soils at the mg kg-1 level with satisfactory performance. Results were compared and validated against AAS reference methodology, with correlations R2>0.948 for the four heavy metals considered.