Bismuth-Coated Screen-Printed Microband Electrodes for On-Field Labile Cadmium Determination

Performances of a screen-printed microband electrode prepared by ex situ bismuth deposition are reported. According to the low bismuth toxicity, this electrode represents,in environmentally friendly alternative to mercury modified sensors, particularly for on-field measurements. The electrochemical behaviour Of the microband electrode has been Studied and is in agreement with microelectrode theory before and after bismuth modification. Sensitive cadmium analysis achieved in nondeaerated and unstirred Solutions leads to a detection limit of 1.3 mu g L-1 using SWASV for 120 s deposition time. This sensor has been successfully applied to a nontreated river water sample.