title: Immobilization of flavoproteins on silicon: effect of cross-linker chain length on enzyme activity.
abstract: The effect of cross-linker chain length on the activities of choline oxidase (ChO) and glucose oxidase (GOx) immobilized on oxidized silicon wafers has been investigated for the cross-linkers N-succinimidyl 4-maleimido-butyrate (GMBS) and N-succinimidyl 6-maleimidocaproate (EMCS). Enzyme activities were determined with an indirect fluorometric assay based on the production of hydrogen peroxide. Immobilization of ChO or GOx onto oxidized silicon with either cross-linker resulted in an 86-99% loss in enzymatic activity relative to the soluble form of the flavoprotein. However, the different cross-linkers had distinctly different effects on enzyme activity: EMCS-immobilized GOx was four times more active than GMBS-immobilized GOx; EMCS-immobilized ChO had a sevenfold higher activity than GMBS-immobilized ChO.
authors.affiliation: Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Washington, DC 20375-5000.
authors.forename: K M
authors.initials: KM
authors.lastname: Rusin
authors.forename: T L
authors.initials: TL
authors.lastname: Fare
authors.forename: J Z
authors.initials: JZ
authors.lastname: Stemple
mesh_terms: D000429:Alcohol Oxidoreductases / Q000737:chemistry*; D003432:Cross-Linking Reagents / Q000737:chemistry*; D004800:Enzymes, Immobilized / Q000737:chemistry*; D005470:Fluorometry; D005949:Glucose Oxidase / Q000737:chemistry*; D007700:Kinetics; D008956:Models, Chemical; D015394:Molecular Structure; D012825:Silicon / Q000737:chemistry*; D012995:Solubility
chemical_list: D003432:Cross-Linking Reagents; D004800:Enzymes, Immobilized; D000429:Alcohol Oxidoreductases; C019888:choline oxidase; D005949:Glucose Oxidase; D012825:Silicon