Electrochemical sensor based on polystyrene sulfonate-carbon nanopowders composite for Cu (II) determination.

A differential pulse anodic stripping voltammetric (DPASV) method, with an open circuit (OC) approach in the pre-concentration step has been developed for copper ion determination at very low concentration level using a sensor based on a polystyrene sulfonate-carbon nanopowders (PSS-CnP) composite. This composite material is easily prepared from ultrasonic assisted dispersions of CnP in aqueous solution of PSS. For preparation of sensor devices, a reproducible and inexpensive drop coating procedure of the surface of home-made pencil graphite electrodes (PGEs) using a CnP dispersion in PSS was performed. At the optimal conditions for accumulation (0.01molL(-1) KNO3 at pH 3) and measurement steps (a reduction potential of -0.5V for 60s and then, an anodic DPV scan) and using a pre-concentration time of 300s, the limit of detection was 0.11µgL(-1) (1.73nM). This OC-DPASV method using the PSS-CnP-PGE sensor was successfully employed for Cu(II) determination in mineral, river and sea water samples.