Electrochemical immunoassay at a 17β-estradiol self-assembled monolayer electrode using a redox marker

Abstract

A simple electrochemical immunoassay was demonstrated using a 17beta-estradiol modified electrode. 17beta-estradiol was immobilized on the gold electrode surface with a self-assembly technique. The specific binding between estradiol antibody and 17beta-estradiol on the electrode surface was evaluated by monitoring the change in the electrode response with three hydrophilic redox markers. The decrease in the electrode response for the redox marker was observed, when the antibody was bound to the estradiol self-assembled monolayer (SAM) electrode surface. The change in the electrode response of the redox marker is attributed to the steric hindrance between the antibody on the electrode surface and the redox marker. The relative standard deviation at 30 microg ml(-1) estradiol antibody was 4.1% (n = 3). The competitive reaction between the antigen in the solution and 17beta-estradiol immobilized on the electrode surface for the limited binding sites on the antibody produced an increase in the electrode response with hydroquinone as the marker. The binding affinity of three antigens including 17beta-estradiol to the estradiol antibody was evaluated. Furthermore, the result obtained from this method was compared with the previously reported enzyme binding assay using the biotinylated estradiol and the biotin-immobilized microtiter plate.

Magnetic molecularly imprinted nanoparticles based on dendritic-grafting modification for determination of estrogens in plasma samples

“…The most potent naturally occurring estrogen is estradiol (E2), which is converted to the less potent estrone (E1) in liver, and then metabolized to estriol (E3) that has limited estrogenic activity. A deficiency of estradiol is often related to such diseases as menopausal symptoms or heart diseases and osteoporosis [1]. In addition, estrogens have strong physical activity, and the concentration of estrogens has direct influence on human life (especially pregnant women and fetuses) [2][3][4][5].…”

Functionalization of a Diamond Surface through N2 and H2 Irradiation for Estrogen (17��-estradiol) Aptamer Sensing

“…(4) It is an important diagnostic marker of various chemical conditions associated with sex hormone imbalance, such as puberty, fertility, ovarian tumor, prostate cancer, and breast cancer. (5) The rapid effect of E2 can cause several diseases as well as birth defects, development disorders in humans in low and high concentrations (natural and synthetic), and harmful effects in fish. (5,6) In this report, we demonstrate the detection of E2 by using an aptamer-based biosensor.…”

“…(5) The rapid effect of E2 can cause several diseases as well as birth defects, development disorders in humans in low and high concentrations (natural and synthetic), and harmful effects in fish. (5,6) In this report, we demonstrate the detection of E2 by using an aptamer-based biosensor.…”

Multimode sensors as new tools for molecular recognition of testosterone, dihydrotestosterone and estradiol in children's saliva

“…E 2 is a steroid hormone mainly secreted by the ovaries, known for its critical impact on sexual functioning, bone structure and fertility status. E 2 deficiency is often correlated with heart diseases, osteoporosis and with early or late puberty (Kuramitz et al, 2003;Kelly and Moses, 2005;Cesario and Hughes, 2007;Honour, 2010;Zawatski and Lee, 2013). T 2 , chemically known as 17β-hydroxyandrost-4-en-3-one or α-4-androsten-17β-ol-3one, is a steroid hormone, too, having the most potent androgenic properties.…”