title: Enzymatically synthesized polyaniline layer for extension of linear detection region of amperometric glucose biosensor.
abstract: In this article a new method for fabrication of enzymatic electrodes suitable for design of amperometric glucose biosensor and/or anode of biofuel cell powered by glucose is presented. Glucose oxidase (GOx) E.C. 1.1.3.4. from Penicillium vitale was immobilized on the carbon rod electrode by cross-linking it with glutaraldehyde (GOx-electrode). Catalytic activity of immobilized GOx was exploited for polymerisation of aniline by taking a high concentration of hydrogen peroxide produced during the catalytic action of immobilized GOx and locally lowered pH due to the formation of gluconic acid; it created optimal conditions for the polymerisation of aniline. The GOx layer was self-encapsulated within formed polyaniline (PANI) matrix (GOx/PANI-electrode). Properties of the GOx/PANI-electrode have been studied and results were compared with GOx-electrode. The results show that the upper detection limit of glucose using GOx-electrode was dramatically changed by the formation of PANI layer. An increase in the upper detection limit, optimal pH region for operation and stability of GOx based electrode modified by PANI was detected when comparing that of an unmodified GOx-electrode.
authors.affiliation: NanoTechnas-Center of Nanotechnology and Material Science, Faculty of Chemistry, Vilnius University, Naugarduko 24, 03225 Vilnius, Lithuania.
authors.forename: Asta
authors.initials: A
authors.lastname: Kausaite-Minkstimiene
authors.forename: Viktor
authors.initials: V
authors.lastname: Mazeiko
authors.forename: Almira
authors.initials: A
authors.lastname: Ramanaviciene
authors.forename: Arunas
authors.initials: A
authors.lastname: Ramanavicius
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry*; D015374:Biosensing Techniques / Q000295:instrumentation*; D003217:Conductometry / Q000295:instrumentation*; D004800:Enzymes, Immobilized / Q000737:chemistry; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005947:Glucose / Q000032:analysis*; D005949:Glucose Oxidase / Q000737:chemistry*; D016014:Linear Models
chemical_list: D000814:Aniline Compounds; D004800:Enzymes, Immobilized; C416807:polyaniline; D005949:Glucose Oxidase; D005947:Glucose