Modified glucose oxidase methods

In contrast to the molecular wire of molecular interface, electron mediators are covalently bound to a redox enzyme in such a manner as an electron tunneling pathway is formed within the enzyme molecule. Therefore, enzyme-bound mediators work as molecular interface between an enzyme and an electrode. Degani et al. proposed the intramolecular electron pathway of ferrocene molecules which were covalently bound to glucose oxidase [ 4 ]. However, few fabrication methods have been developed to form a monolayer of mediator-modified enzymes on the electrode surface. We have succeeded in development of a novel preparation of the electron transfer system of mediator-modified enzyme by self-assembly in a porous gold-black electrode as schematically shown in Fig.12 [14]. 

Sakanaka M, Shibasaki T, Lederis K (1987) Corticotropin releasing factor-like immimoreac-tivityin the rat brain as revealed by a modified cobalt-glucose oxidase-diaminobenzidine method. J Comp Neurol 260 256-298... 

All electrodes react with their environment via the surfaces in ways which will determine their electrochemical performance. Properly selected surface modification can effectively enhance the electrode heterogeneous catalysis property, especially selectivity and activity. The bulk materials can be chosen to provide mechanical, chemical, electrical, and structural integrity. In this part, several surface modification methods will be introduced in terms of metal film deposition, metal ion implantation, electrochemical activation, organic surface coating, nanoparticle deposition, glucose oxidase (GOx) enzyme-modified electrode, and DNA-modified electrode. 

GOD-PAP glucose oxidase/p-aminophenazone method (modified Trinder reaction)... 

Degani Y, Heller A (1988) Direct electrical communication between chemically modified enzymes and metal electrodes. 2. Methods for bonding electron-transfer relays to glucose oxidase and D-amino-acid oxidase. J Am Chem Soc 110 2615-2620... 

Degani, Y., Heller, A., Direct Electrical Communication between Chemically Modified Enzymes and Metal Electrodes. 2. Methods for Bonding Electron-Transfer Relays to Glucose Oxidase and D-Amino-Acid Oxidase , J. Am. Chem. Soc. 110 (1988) 2615-2620. 

An enzyme sensor for glucose fabricated by the electrochemical polymerization method is described. Electropolymerized films of 2,2 -bithiophene is used to immobilized glucose oxidase at platinum electrodes. The responses of the enzyme-polymer electrodes toward glucose are analyzed under various conditions. The relation between performance of the polymer-modified electrode and properties of the polymer formed is also discussed. 

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