title: Nanomolar hydrogen peroxide detection using horseradish peroxidase covalently linked to undoped nanocrystalline diamond surfaces.
abstract: In this article, we report on the low-level detection of hydrogen peroxide, a key player in the redox signaling pathway and a toxic product in the cellular system, using a colorimetric solution assay. Amine-terminated undoped nanocrystalline diamond thin films were grown on glass using a linear-antenna microwave plasma CVD process. The diamond surface consists mainly of -NH(2) termination. The aminated diamond surface was decorated with horseradish peroxidase (HRP) enzyme using carbodiimide coupling chemistry. The success of the HRP immobilization was confirmed by X-ray photoelectron spectroscopy (XPS). The enzymatic activity of immobilized HRP was determined with a colorimetric test based on the HRP-catalyzed oxidation of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sufonic acid (ABTS) in the presence of hydrogen peroxide. The surface coverage of active HRP was estimated to be Γ = 7.3 × 10(13) molecules cm(-2). The use of the functionalized diamond surface as an optical sensor for the detection of hydrogen peroxide with a detection limit of 35 nM was demonstrated.
authors: Institut de Recherche Interdisciplinaire (USR 3078), Université de Lille1, Parc de la Haute Borne, 50 Avenue de Halley, BP 70478, 59658 Villeneuve d'Ascq, France.
authors: Qi
authors: Q
authors: Wang
authors: Alexander
authors: A
authors: Kromka
authors: Jana
authors: J
authors: Houdkova
authors: Oleg
authors: O
authors: Babchenko
authors: Bohuslav
authors: B
authors: Rezek
authors: Musen
authors: M
authors: Li
authors: Rabah
authors: R
authors: Boukherroub
authors: Sabine
authors: S
authors: Szunerits
mesh_terms: D003460:Crystallization; D018130:Diamond; D006735:Horseradish Peroxidase / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000032:analysis*; D049329:Nanostructures; D056951:Photoelectron Spectroscopy
chemical_list: D018130:Diamond; D006861:Hydrogen Peroxide; D006735:Horseradish Peroxidase