title: Direct electrochemistry of glucose oxidase immobilized on a hexagonal mesoporous silica-MCM-41 matrix.
abstract: The direct electrochemistry of glucose oxidase (GOD) immobilized on a hexagonal mesoporous silica modified glassy carbon electrode was investigated. The adsorbed GOD displayed a pair of redox peaks with a formal potential of -417 mV in 0.1 M pH 6.1 phosphate buffer solution (PBS). The response showed a diffusion-controlled electrode process with a two-electron transfer coupled with a two-proton transfer reaction process. GOD immobilized on a hexagonal mesoporous silica retained its bioactivity and stability. In addition, the immobilized GOD could electrocatalyze the oxidation of glucose to gluconlactone by taking ferrocene monocarboxylic acid (FMCA) as a mediator in N(2) saturated solutions, indicating that the electrode may have the potential application in biosensors to analyze glucose. The sensor could exclude the interference of commonly coexisted uric acid, p-acetaminophenol and ascorbic acid and diagnose diabetes very fast and sensitively. This work demonstrated that the mesoporous silica provided a novel matrix for protein immobilization and the construction of biosensors.
authors.affiliation: Department of Chemistry, Nanjing Normal University, Nanjing, PR China. daizhihuii@njnu.edu.cn <daizhihuii@njnu.edu.cn>
authors.forename: Z H
authors.initials: ZH
authors.lastname: Dai
authors.forename: J
authors.initials: J
authors.lastname: Ni
authors.forename: X H
authors.initials: XH
authors.lastname: Huang
authors.forename: G F
authors.initials: GF
authors.lastname: Lu
authors.forename: J C
authors.initials: JC
authors.lastname: Bao
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D020099:Coated Materials, Biocompatible / Q000737:chemistry; D004563:Electrochemistry / Q000295:instrumentation / Q000379:methods*; D004800:Enzymes, Immobilized / Q000737:chemistry; D005947:Glucose / Q000032:analysis* / Q000737:chemistry*; D005949:Glucose Oxidase / Q000737:chemistry*; D016062:Porosity; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012822:Silicon Dioxide / Q000737:chemistry*
chemical_list: D020099:Coated Materials, Biocompatible; D004800:Enzymes, Immobilized; D012822:Silicon Dioxide; D005949:Glucose Oxidase; D005947:Glucose