Development of an optical sensor for determination of zinc by application of PC-ANN

A very sensitive and reversible optical chemical sensor based on dithizone as chromoionophore immobilized within a plasticized carboxylated PVC film for Zn2+ determination is described. At optimum conditions (i.e. pH 5.0), the proposed sensor displays a linear response to Zn2+ over 5.0 × 10−8–5.0 × 10−6 mol L−1 range. This range was improved to 2.5 × 10−8–5.8 × 10−5 mol L−1 range by applying principle component-feed forward artificial neural network with back-propagation training algorithm (PC-ANNB). Detection limit of 8.0 × 10−9 mol L−1 was obtained. The sensor is fully reversible within the dynamic range and the response time (t95%) is approximately 4 min under batch conditions. In addition to its high stability and reproducibility, the sensor shows good selectivity towards Zn2+ ion with respect to common metal cations. The sensor was successfully applied for determination of Zn2+ ion in hair sample.