Abstract: The present invention provides a new device for use in measuring lead levels in biological and environmental samples. Using square wave coulometry and colloidal gold particles impregnated on carbon electrodes, the present invention provides a rapid, reliable, portable and inexpensive means of detecting low lead levels. The colloidal gold modified electrodes have microelectrode array characteristics and produce significantly higher stripping detection signals for lead than are produced at bulk gold electrode surfaces. The method is effective in determining levels of lead down to at least 5 .mu.g/dL in blood samples as small as 10 .mu.L.

Abstract: The invention relates to methods of determining micromolar levels of lead ion in various fluids, including blood. Detection of lead or other heavy metal ion concentrations as low as 1 .mu.g/dL is achieved. The methods are adaptable to the detection of low levels of lead in whole blood, employing a novel separation and release of lead ion from lead chelating agents. The disclosed methods employ isocitrate dehydrogenase-based electrodes which are particularly suited for detecting nanomolar levels of lead.

Abstract: An apparatus for conducting two or more simultaneous measurements of electrochemiluminescent (ECL) phenomena includes a cell in which a sample including an ECL moiety may be induced to repeatedly emit light in response to electrochemical energy applied by, for example, a working voltammetric electrode. Two or more light detectors such as photomultiplier tubes receive the emitted light at respective wavelengths indicative of respective analytes of interest in the sample.