Semicontinuous monitoring of cadmium and lead with a screen-printed sensor modified by a membrane

The analytical performances of the developed sensor were evaluated in laboratory for the semicontinuous monitoring of Cd and Ph in water samples at mu g L-1 level. The effects of oxygen, pH, and stirring on the voltammetric response of these metals were investigated. The O-2 removal did not allow to improve the peak current. In return, stirring appeared indispensable to avoid the impoverishment of metals in the diffusion layer. The necessity to control the pH and the solution evolution in laboratory experiments was also clearly established. The semicontinuous monitoring of Cd and Ph was then performed for 42 h in tap water and demonstrated that sensor is a promised tool for semicontinuous environmental analyses.