Bismuth‐Coated Screen‐Printed Electrodes for Stripping Voltammetric Measurements of Trace Lead

Bismuth-coated screen-printed carbon electrodes offer reliable quantitation of trace lead in connection to anodic stripping voltammetry. Such use of bismuth films (instead of mercury coatings) does not affect the reliability of stripping measurements of trace lead. The influence of various experimental variables upon the stripping lead signal at the bismuth-coated thick-film sensor is explored. The square-wave voltammetric stripping response is highly linear over the 10–100 ppb lead range examined (2 min deposition), with a detection limit of 0.3 ppb (10 min deposition) and good precision (RSD=7.4 % at 20 ppb lead). The rapid square-wave stripping voltammetric mode facilitates the use of nondeaerated samples. Applicability to drinking water samples is demonstrated. The attractive behavior of the new disposable “mercury-free” carbon strip electrodes, coupled with the negligible toxicity of bismuth, hold great promise for “one-shot” decentralized lead testing (including blood lead screening).