title: Electrochemical immunosensor for sensitive determination of the anorexigen peptide YY at grafted reduced graphene oxide electrode platforms.
abstract: The first electrochemical immunosensor for the determination of peptide YY is reported in this paper. A novel electrochemical platform, prepared by the electrochemical grafting of the diazonium salt of 4-aminobenzoic acid onto a reduced graphene oxide-modified glassy carbon electrode, was used, on which the covalent immobilization of specific anti-PYY antibodies was accomplished. The HOOC-Phe-rGO/GCEs were characterized using cyclic voltammetry and electrochemical impedance spectroscopy. The different variables affecting the preparation of the modified electrodes and the performance of the immunosensor were optimized. Under the optimized conditions, a calibration plot for PYY showing a linear range extending between 10(-4) and 10(2) ng mL(-1) was found. This range is adequate for the determination of this protein in real samples, since the expected concentration in human serum is around 100 pg mL(-1). The limit of detection was 0.01 pg mL(-1) of PYY. The immunosensor exhibited good reproducibility of the PYY measurements, excellent storage stability and selectivity, as well as a shorter assay time than those of ELISA kits. The usefulness of the immunosensor for the analysis of real samples was demonstrated by analyzing human serum samples spiked with PYY at three concentration levels.
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, University Complutense of Madrid, 28040-Madrid, Spain. yseo@quim.ucm.es.
authors.forename: S
authors.initials: S
authors.lastname: Guerrero
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, University Complutense of Madrid, 28040-Madrid, Spain. yseo@quim.ucm.es.
authors.forename: G
authors.initials: G
authors.lastname: Martínez-García
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, University Complutense of Madrid, 28040-Madrid, Spain. yseo@quim.ucm.es.
authors.forename: V
authors.initials: V
authors.lastname: Serafín
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, University Complutense of Madrid, 28040-Madrid, Spain. yseo@quim.ucm.es.
authors.forename: L
authors.initials: L
authors.lastname: Agüí
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, University Complutense of Madrid, 28040-Madrid, Spain. yseo@quim.ucm.es.
authors.forename: P
authors.initials: P
authors.lastname: Yáñez-Sedeño
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, University Complutense of Madrid, 28040-Madrid, Spain. yseo@quim.ucm.es.
authors.forename: J M
authors.initials: JM
authors.lastname: Pingarrón
mesh_terms: D058266:Dielectric Spectroscopy / Q000379:methods; D055664:Electrochemical Techniques / Q000379:methods*; D004566:Electrodes; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D057230:Limit of Detection; D008958:Models, Molecular; D010084:Oxidation-Reduction; D019894:Peptide YY / Q000032:analysis / Q000097:blood*; D015203:Reproducibility of Results
chemical_list: D019894:Peptide YY; D006108:Graphite