title: Electrocatalytic tuning of biosensing response through electrostatic or hydrophobic enzyme-graphene oxide interactions.
abstract: The effect of graphene oxidative grades upon the conductivity and hydrophobicity and consequently the influence on an enzymatic biosensing response is presented. The electrochemical responses of reduced graphene oxide (rGO) have been compared with the responses obtained from the oxide form (oGO) and their performances have been accordingly discussed with various evidences obtained by optical techniques. We used tyrosinase enzyme as a proof of concept receptor with interest for phenolic compounds detection through its direct adsorption onto a screen-printed carbon electrode previously modified with oGO or rGO with a carbon-oxygen ratio of 1.07 or 1.53 respectively. Different levels of oGO directly affect the (bio)conjugation properties of the biosensor due to changes at enzyme/graphene oxide interface coming from the various electrostatic or hydrophobic interactions with biomolecules. The developed biosensor was capable of reaching a limit of detection of 0.01 nM catechol. This tuning capability of the biosensor response can be of interest for building several other biosensors, including immunosensors and DNA sensors for various applications.
authors: Nanobioelectronics and Biosensors Group, Catalan Institute of Nanoscience and Nanotechnology, ICN2 Campus de la UAB, 08193 Bellaterra, Barcelona, Spain.
authors: Luis
authors: L
authors: Baptista-Pires
authors: LEITAT Technological Center, 08225 Terrasa, Spain.
authors: Briza
authors: B
authors: Pérez-López
authors: Nanobioelectronics and Biosensors Group, Catalan Institute of Nanoscience and Nanotechnology, ICN2 Campus de la UAB, 08193 Bellaterra, Barcelona, Spain.
authors: Carmen C
authors: CC
authors: Mayorga-Martinez
authors: Nanobioelectronics and Biosensors Group, Catalan Institute of Nanoscience and Nanotechnology, ICN2 Campus de la UAB, 08193 Bellaterra, Barcelona, Spain.
authors: Eden
authors: E
authors: Morales-Narváez
authors: Oxide Nanoelectronics Group, Catalan Institute of Nanoscience and Nanotechnology, ICN2 Campus de la UAB, 08193 Bellaterra, Barcelona, Spain.
authors: Neus
authors: N
authors: Domingo
authors: Catalan Institute of Nanoscience and Nanotechnology, ICN2 Campus de la UAB, 08193 Bellaterra, Barcelona, Spain.
authors: Maria Jose
authors: MJ
authors: Esplandiu
authors: Phononic and Photonic Nanostructures, Catalan Institute of Nanoscience and Nanotechnology, ICN2 Campus de la UAB, 08193 Bellaterra, Barcelona, Spain.
authors: Francesc
authors: F
authors: Alzina
authors: Phononic and Photonic Nanostructures, Catalan Institute of Nanoscience and Nanotechnology, ICN2 Campus de la UAB, 08193 Bellaterra, Barcelona, Spain; ICREA, Institució Catalana de Recerca i Estudis Avançats, 08010 Barcelona, Spain.
authors: Clivia M
authors: CM
authors: Sotomayor-Torres
authors: Nanobioelectronics and Biosensors Group, Catalan Institute of Nanoscience and Nanotechnology, ICN2 Campus de la UAB, 08193 Bellaterra, Barcelona, Spain; ICREA, Institució Catalana de Recerca i Estudis Avançats, 08010 Barcelona, Spain. Electronic address: arben.merkoci@icn.cat.
authors: Arben
authors: A
authors: Merkoçi
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D002384:Catalysis; D002396:Catechols / Q000032:analysis* / Q000378:metabolism; D055664:Electrochemical Techniques / Q000295:instrumentation; D004800:Enzymes, Immobilized / Q000737:chemistry / Q000378:metabolism*; D004867:Equipment Design; D006108:Graphite / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D057230:Limit of Detection; D008958:Models, Molecular; D014442:Monophenol Monooxygenase / Q000737:chemistry / Q000378:metabolism*; D010084:Oxidation-Reduction; D010087:Oxides / Q000737:chemistry*; D055672:Static Electricity
chemical_list: D002396:Catechols; D004800:Enzymes, Immobilized; D010087:Oxides; D006108:Graphite; D014442:Monophenol Monooxygenase; C034221:catechol
keywords: Electrocatalytic tuning; Electrostatic interactions; Hydrophobic interactions; Oxidized graphene oxide; Reduced graphene oxide