title: Biosensor based on laccase immobilized on plasma polymerized allylamine/carbon electrode.
abstract: In this work, a simple and rapid method was used to functionalize carbon electrode in order to efficiently immobilize laccase for biosensor application. A stable allylamine coating was deposited using a low pressure inductively excited RF tubular plasma reactor under mild plasma conditions (low plasma power (10 W), few minutes) to generate high density amine groups (N/C ratio up to 0.18) on rough carbon surface electrodes. The longer was the allylamine plasma deposition time; the better was the surface coverage. Laccase from Trametes versicolor was physisorbed and covalently bound to these allylamine modified carbon surfaces. The laccase activities and current outputs measured in the presence of 2,2'-azinobis-(3-ethylbenzothiazole-6-sulfonic acid) (ABTS) showed that the best efficiency was obtained for electrode plasma coated during 30 min. They showed also that for all the tested electrodes, the activities and current outputs of the covalently immobilized laccases were twice higher than the physically adsorbed ones. The sensitivity of these biocompatible bioelectrodes was evaluated by measuring their catalytic efficiency for oxygen reduction in the presence of ABTS as non-phenolic redox substrate and 2,6-dimethoxyphenol (DMP) as phenolic one. Sensitivities of around 4.8 μA mg(-1)L and 2.7 μA mg(-1)L were attained for ABTS and DMP respectively. An excellent stability of this laccase biosensor was observed for over 6 months.
authors.affiliation: Laboratoire de Génie des Procédés Plasma et Traitements de Surface, Université Pierre et Marie Curie-Chimie ParisTech, Paris, France. malika.ardhaoui@ucd.ie
authors.forename: Malika
authors.initials: M
authors.lastname: Ardhaoui
authors.forename: Sudhir
authors.initials: S
authors.lastname: Bhatt
authors.forename: Meihui
authors.initials: M
authors.lastname: Zheng
authors.forename: Denis
authors.initials: D
authors.lastname: Dowling
authors.forename: Claude
authors.initials: C
authors.lastname: Jolivalt
authors.forename: Farzaneh Arefi
authors.initials: FA
authors.lastname: Khonsari
mesh_terms: D000499:Allylamine / Q000737:chemistry*; D055162:Biocatalysis; D015374:Biosensing Techniques; D002244:Carbon / Q000737:chemistry*; D055664:Electrochemical Techniques; D004566:Electrodes; D004800:Enzymes, Immobilized / Q000737:chemistry / Q000378:metabolism; D042845:Laccase / Q000737:chemistry / Q000378:metabolism*; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry / Q000378:metabolism; D058105:Polymerization; D055454:Trametes / Q000201:enzymology
chemical_list: D004800:Enzymes, Immobilized; D000499:Allylamine; D002244:Carbon; D042845:Laccase; D010100:Oxygen