A Novel Cell Design for the Improved Stripping Voltammetric Detection of Zn(II), Cd(II), and Pb(II) on Commercial Screen-Printed Strips by Bismuth Codeposition in Stirred Solutions

A novel electrochemical cell design is proposed to allow fast, reproducible and highly efficient convective transport of dissolved substances to screen-printed electrochemical three-electrode strips mounted on miniaturized plastic vessels, with the goal of improving detection limits in disposable electrochemical stripping field sensors. The experimental configuration has been tested for accumulation of the selected heavy metals ions Zn(II), Cd(II), and Pb(II), codeposited with bismuth ions on a carbon disk screen-printed working electrode before detection by square wave anodic stripping voltammetry. Chemical and instrumental variables of the proposed device and associate electrochemical method were optimized. Selected parameters gave detection limits in the low ng mL(-1) range with moderate deposition time (120 s). Practical applicability was tested on certified water and real samples (tap water and waste water), with acceptable results, suggesting potential usefulness for field environmental monitoring of heavy metals.