ELECTROCHEMICAL DETERMINATION OF LOW BLOOD LEAD CONCENTRATIONS WITH ADISPOSABLE CARBON MICROARRAY ELECTRODE

Lead concentrations in blood samples typical of unexposed individuals are determined by using square-wave anodic stripping voltammetry at a disposable 287-element (15-35-mu m diameter) carbon microarray electro de. Analysis of a series of low Pb-containing samples (blood [Pb] = 17 to 92 mu g/L) by standard addition gives good accuracy (average bias vs graphite furnace atomic absorption spectroscopy = -4 mu g/L) and pr ecision (pooled SD = 7 mu g/L). The signal/noise ratio is improved by about an order of magnitude over that found at a single carbon disk (1 0 mu m diameter), resulting in a detection limit (for the microarray) of 5 mu g/L for a 60-s deposition of sample.