Direct Voltammetric Determination of Total Iron with a Gold Microelectrode Ensemble



The behavior of the Fe(II)/(III) redox system at a Au microelectrode ensemble (Au-MEE) based on a solid composite by means of direct and cyclic voltammetric analysis (VA) is reported. With a simple electrode activation and sample preparation, the influence of dissolved organic substances was eliminated, providing highly sensitive results. The analytical signal was based on the maximum cathodic current (I) of the first derivative (dI/dE), and iron determination within the 0.002–0.04 mg L−1 range was studied. A sensitive LOD (3σ) value of 0.7 µg L−1 for total iron concentration was calculated; total iron determination in different waters was shown.