title: Direct electron transfer glucose biosensor based on glucose oxidase self-assembled on electrochemically reduced carboxyl graphene.
abstract: A glucose biosensor based on direct electron transfer of glucose oxidase (GOD) self-assembled on the surface of the electrochemically reduced carboxyl graphene (ERCGr) modified glassy carbon electrode has been reported. X-ray photoelectron spectroscopy (XPS) analyses of ERCGr indicate most of the oxygen-containing groups such as epoxy/ether groups and hydroxyl groups in the carboxyl graphene were eliminated, while carboxylic acid groups remained. GOD was immobilized on the ERCGr modified glassy carbon electrode via self-assembly. The cyclic voltammetric result of the electrode shows a pair of well-defined and quasi-reversible redox peaks with a formal potential of -0.467 V and a peak to peak separation of 49 mV, revealing that the direct electron transfer between GOD and the electrode has been achieved. The proposed biosensor exhibits a linear response to glucose concentrations ranging from 2 to 18 mM with a detection limit of 0.02 mM. Moreover, this facile, fast, environment-friendly and economical preparation strategy of ERCGr may be extended for the preparation of other graphene based enzyme electrode biosensors.
authors.affiliation: Biosensor National Special Laboratory, Key Laboratory of Biomedical Engineering of Ministry of Education, College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou 310027, PR China.
authors.forename: Bo
authors.initials: B
authors.lastname: Liang
authors.forename: Lu
authors.initials: L
authors.lastname: Fang
authors.forename: Guang
authors.initials: G
authors.lastname: Yang
authors.forename: Yichuan
authors.initials: Y
authors.lastname: Hu
authors.forename: Xishan
authors.initials: X
authors.lastname: Guo
authors.forename: Xuesong
authors.initials: X
authors.lastname: Ye
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D003217:Conductometry / Q000295:instrumentation*; D004566:Electrodes; D004579:Electron Transport; D004595:Electroplating; D004800:Enzymes, Immobilized / Q000737:chemistry; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005947:Glucose / Q000032:analysis* / Q000737:chemistry; D005949:Glucose Oxidase / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry*
chemical_list: D004800:Enzymes, Immobilized; D006108:Graphite; D005949:Glucose Oxidase; D005947:Glucose