title: Hydrogen peroxide biosensor with a supramolecular layer-by-layer design.
abstract: A new sensor design is reported for the construction of an amperometric enzyme biosensor toward H (2)O(2). It was based in the supramolecular immobilization of alternating layers of horseradish peroxidase (either modified with 1-adamantane or beta-cyclodextrin-branched carboxymethylcellulose residues) on Au electrodes coated with polythiolated beta-cyclodextrin polymer. The analytical response of the electrodes, using 1 mM hydroquinone as an electrochemical mediator, increases when the number of enzyme layers increases. The biosensor having three enzyme layers showed a sensitivity of 720 microA/M cm (2) and a detection limit of 2 microM and retained 96% of its initial activity after 30 days of storage. The host-guest supramolecular nature of the immobilization method was confirmed by cyclic voltammetry.
authors.affiliation: Center for Enzyme Technology, University of Matanzas, Matanzas 44740, Cuba.
authors.forename: Conrado
authors.initials: C
authors.lastname: Camacho
authors.forename: Juan C
authors.initials: JC
authors.lastname: Matías
authors.forename: Roberto
authors.initials: R
authors.lastname: Cao
authors.forename: Madyu
authors.initials: M
authors.lastname: Matos
authors.forename: Belkis
authors.initials: B
authors.lastname: Chico
authors.forename: Javier
authors.initials: J
authors.lastname: Hernández
authors.forename: Maria A
authors.initials: MA
authors.lastname: Longo
authors.forename: Maria A
authors.initials: MA
authors.lastname: Sanromán
authors.forename: Reynaldo
authors.initials: R
authors.lastname: Villalonga
mesh_terms: D015374:Biosensing Techniques; D003505:Cyclodextrins / Q000737:chemistry; D006735:Horseradish Peroxidase / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000737:chemistry*
chemical_list: D003505:Cyclodextrins; D006861:Hydrogen Peroxide; D006735:Horseradish Peroxidase