High throughput screening of lead utilising disposable screen printed shallow recessed microelectrode arrays

Abstract

The cathodic stripping voltammetry of lead at disposable screen printed shallow recessed microelectrode arrays has been developed for the first time. The array comprises 6 microdiscs which have radii of 116 (+/-6) microns which are recessed by 4 microns and are separated by 2500 microns from their nearest neighbour in a hexagonal arrangement. The electroanalytical determination of lead was explored in 0.1 M nitric acid and found that using a 120 s deposition time, a detection limit of 3 microM is feasible which is not possible utilising a screen printed graphite macro-electrode. The sensitivity of this analytical protocol can be tailored by varying the deposition time and it is found that increasing this to 320 s facilitates a limit of detection of 39 nM. This methodology is shown to be feasible for the portable and economical screening of lead in river water samples at the levels indicated by the EC Dangerous Substances Directive (76/464/EEC).