title: Carbon nanohorns as a scaffold for the construction of disposable electrochemical immunosensing platforms. Application to the determination of fibrinogen in human plasma and urine.
abstract: We describe in this work a novel electrochemical immunosensor design making use of carbon nanohorns (CNHs) as a scaffold for the preparation of disposable immunosensing platforms for the determination of fibrinogen (Fib). The approach involved the immobilization of Fib onto activated CNHs deposited on screen-printed carbon electrodes (SPCEs) and the implementation of an indirect competitive assay using anti-Fib labeled with horseradish peroxidase (HRP) and hydroquinone (HQ) as the redox mediator. Both CNHs and the Fib-CNHs covalent assembly were characterized by microscopic and electrochemical techniques. The different variables affecting the analytical performance of the amperometric immunosensing strategy were optimized. The calibration plot for Fib allowed a range of linearity between 0.1 and 100 μg/mL (r(2) = 0.994) and a detection limit of 58 ng/mL to be achieved. The Fib-CNHs/SPCEs exhibited an excellent storage stability of at least 42 days. The developed immunosensor provides, in general, an analytical performance better than that reported for other Fib immunosensors and commercial ELISA kits. This simple and relatively low cost immunosensor configuration permitted the sensitive and selective determination of Fib in human plasma and urine.
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.forename: Belit
authors.initials: B
authors.lastname: Garcinuño
authors.forename: María
authors.initials: M
authors.lastname: Moreno-Guzmán
authors.forename: A
authors.initials: A
authors.lastname: González-Cortés
authors.forename: Masako
authors.initials: M
authors.lastname: Yudasaka
authors.forename: Sumio
authors.initials: S
authors.lastname: Iijima
authors.forename: Fernando
authors.initials: F
authors.lastname: Langa
authors.forename: Paloma
authors.initials: P
authors.lastname: Yáñez-Sedeño
authors.forename: José M
authors.initials: JM
authors.lastname: Pingarrón
mesh_terms: D015374:Biosensing Techniques; D002244:Carbon / Q000737:chemistry*; D055664:Electrochemical Techniques / Q000379:methods*; D005340:Fibrinogen / Q000032:analysis* / Q000652:urine; D006801:Humans; D046529:Microscopy, Electron, Transmission; D049329:Nanostructures
chemical_list: D002244:Carbon; D005340:Fibrinogen