Voltammetric behavior and determination of estrogens at Nafion-modified glassy carbon electrode in the presence of cetyltrimethylammonium bromide

A method is described for the determination of estrogens (estradiol, estrone and estriol) by stripping voltammetry. These estrogens yield one well-defined oxidation peak at the Nafion-modified glassy carbon electrode in the presence of cetyltrimethylammonium, bromide (CTAB). The peak current is proportional to the concentration of estradiol in the range from 2.5 x 10(-8) to 1.5 x 10(-6) mol/l, and the detection limit is 1 x 10(-9) mol/l after accumulation of 6 min. The total amounts of estrogens in the blood serums were determined using the voltammetric method, and the average recovery was 106.04%. The mechanism of the oxidation of estradiol was investigated by electrochemical techniques and LTV spectra. (C) 2002 Elsevier Science B.V. All rights reserved.