Lead(II)-Selective Membrane Electrode Based on Tetraphenylporphyrin

Abstract

ABSTRACT A PVC membrane electrode for Pb2 ions based on tetraphenylporphyrin was prepared. The sensor exhibits a Nernstian response for lead ions over a wide concentration range (1.0 x 10−5-1.0 x 10−2 M). The limit of detection is 8.5 x 10−6M. It has a response time of 15 s and can be used for at least three months without any divergence in potential. The proposed electrode shows a fairly good discriminating ability towards Pb2 ion in comparison to some alkali, alkaline earth, transition and heavy metal ions. The electrode can be used in the pH range 5.0 to 7.5. It was used as an indicator electrode in potentiometric titration of lead ion.