title: Ultrasensitive detection of adrenocorticotropin hormone (ACTH) using disposable phenylboronic-modified electrochemical immunosensors.
abstract: This work reports for the first time an electrochemical immunosensor for the determination of adrenocorticotropin hormone (ACTH). The immunoelectrode design involves the use of amino phenylboronic acid for the oriented immobilization of anti-ACTH antibodies onto screen-printed carbon modified electrode surfaces. A competitive immunoassay between the antigen and the biotinylated hormone for the binding sites of the immobilized antibody was performed. The electroanalytical response was generated by using alkaline phosphatase-labelled streptavidin and 1-naphtyl phosphate as the enzyme substrate. The electrochemical oxidation of the enzyme reaction product, 1-naphtol, measured by differential pulse voltammetry was employed to monitor the affinity reaction. Under the optimized working conditions, an extremely low detection limit of 18 pg/L was obtained. Cross-reactivity was evaluated against other hormones (cortisol, estradiol, testosterone, progesterone, hGH and prolactin) and the obtained results demonstrated an excellent selectivity. The developed immunosensor was applied to a human serum sample containing a certified amount of ACTH with good results.
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, University Complutense of Madrid, 28040 Madrid, Spain.
authors.forename: María
authors.initials: M
authors.lastname: Moreno-Guzmán
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, University Complutense of Madrid, 28040 Madrid, Spain.
authors.forename: Irene
authors.initials: I
authors.lastname: Ojeda
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, University Complutense of Madrid, 28040 Madrid, Spain.
authors.forename: Reynaldo
authors.initials: R
authors.lastname: Villalonga
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, University Complutense of Madrid, 28040 Madrid, Spain.
authors.forename: Araceli
authors.initials: A
authors.lastname: González-Cortés
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, University Complutense of Madrid, 28040 Madrid, Spain. Electronic address: yseo@quim.ucm.es.
authors.forename: Paloma
authors.initials: P
authors.lastname: Yáñez-Sedeño
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, University Complutense of Madrid, 28040 Madrid, Spain.
authors.forename: José M
authors.initials: JM
authors.lastname: Pingarrón
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000032:analysis* / Q000097:blood / Q000276:immunology; D055910:Antibodies, Immobilized; D000918:Antibody Specificity; D015374:Biosensing Techniques / Q000379:methods* / Q000706:statistics & numerical data; D001774:Blood Chemical Analysis / Q000379:methods / Q000706:statistics & numerical data; D001897:Boronic Acids; D003429:Cross Reactions; D055664:Electrochemical Techniques; D006728:Hormones / Q000032:analysis; D006801:Humans; D007118:Immunoassay / Q000379:methods* / Q000706:statistics & numerical data; D012680:Sensitivity and Specificity
chemical_list: D055910:Antibodies, Immobilized; D001897:Boronic Acids; D006728:Hormones; D000324:Adrenocorticotropic Hormone; C010686:benzeneboronic acid