Chemical Sensor for Detection of Lead Levels in Herbal Medicine

Abstract

A new tube type Pb²⁺ sensor made from two types of mixtures, namely clay-PbI₂ and chitosan-PbI₂ were prepared. An electromotive force (EMF) with Ag/AgCl as the reference electrode was used as the output signal. The highest performance of the Pb²⁺ sensor from clay-PbI₂ was obtained at Pb²⁺ solutions in HNO₃ and pH 3 with sensor sensitivity of 20.67 mV/decade. The highest performance of the Pb²⁺ sensor from chitosan-PbI₂ was obtained at Pb²⁺ solutions in demineralized water with sensor sensitivity of 32.49 mV / decade. Application of the two sensors on several commercial herbal samples resulted in an average recovery of 85.62% and 94.10% for sensor from chitosan-PbI₂ and clay-PbI₂, respectively