AbstractChemically modified electrodes (CMEs) containing incorporated crown ether and cryptand ligands as modifiers were evaluated for their ability to preconcentrate metal cations prior to quantitation by conventional voltammetric methods. Stable CMEs were formed for 18‐crown‐6, dibenzo‐18‐crown‐6, poly(dibenzo‐18‐crown‐6), dibenzo‐24‐crown‐8, and 2.2.2‐cryptand by mixing the desired amount of the ligand into carbon paste. The resulting electrodes exhibited complexing capabilities that were similar to those of the free ligands. In particular, the CMEs were very reactive toward Pb2+and Hg2+. Pb2+uptake was sufficiently strong that a detection limit of 1 μM was obtained following a 20‐sec exposure to the sample and transfer to a blank electrolysis solution for differential pulse voltammetric analysis. Accurate quantitation of micromolar levels of Pb in water and urine reference standards was achieved at the CMEs by means of a simple procedure requiring minimal sample preparation. Finally, the analytical characteristics of CME preconcentration were directly compared to those of the electrodeposition approach ordinarily employe
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