Screen-printed anodic stripping voltammetric sensor containing HgO for heavy metal analysis

A screen-printed disposable sensor for the anodic stripping voltammetric (A SV) analysis of heavy metals was prepared by integrating a HgO-modified wor king electrode, Ag/AgCl reference electrode, and carbon counter electrode o n a polycarbonate strip. The working electrode was screen-printed with phen ol resin-based carbon ink containing fine particles of mercuric oxide as a built-in mercury precursor. The mercuric oxide particles exposed on the sur face were reduced to fine mercury droplets by in situ or pre-cathodic condi tioning in order to allow them to behave as heavy metal collectors in the a nodic stripping analysis. The reference and counter electrodes were also sc reen-printed using commercial silver paste ink modified with finely ground AgCl powder and commercial carbon ink, respectively. The analytical charact eristics of the sensor were evaluated using Ph and Cd as probe metals. Deta iled preparation procedures and analytical characteristics of the sensor ar e described. (C) 2001 Elsevier Science B.V. All rights reserved.