Polyvinylferrocenium modified Pt electrode for anaerobic glucose monitoring.
An amperometric enzyme electrode for the determination of glucose under anaerobic solution conditions was developed by immobilizing glucose oxidase and then by adsorbing ferrocene in polyvinylferrocenium matrix coated on a Pt electrode surface. The amperometric response due to the electrooxidation of ferrocene that the reduced flavin adenine dinucleotide centers of glucose oxidase was measured at a constant potential. The response characteristics of the enzyme electrode were investigated. The effects of the thickness of the polymeric film, the amount of the enzyme immobilized, the amount of the mediator, the glucose concentration, the applied potential, operating pH and temperature on the response of the enzyme electrode were studied. The response time and the optimum pH were found to be 30-40 s and pH 7.4 at 25 degrees C, respectively. The linear response was observed up to 5.0 mM glucose concentration that the produced detectable current was 0.0075 mM glucose concentration. The activation energy (E(a)) of immobilized enzyme reaction was calculated to be 41.3 kJ mol(-1) from the Arrhenius plot. The apparent Michaelis-Menten constant (K(Mapp)) was found to be 6.05 mM glucose according to the Lineweaver-Burk graph of the Michaelis-Menten equation under the optimum conditions. The interference signal due to the most common electrochemical interfering species was also evaluated.
Gülce
Ahmet
A
Department of Chemical Engineering, Selçuk University, 42031 Konya, Turkey. hgulce@selcuk.edu.tr
Gülce
Handan
H
D000327:Adsorption; D000693:Anaerobiosis; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D004563:Electrochemistry / Q000295:instrumentation / Q000379:methods*; D005296:Ferrous Compounds / Q000737:chemistry*; D005947:Glucose / Q000032:analysis*; D005949:Glucose Oxidase / Q000737:chemistry*; D010984:Platinum / Q000737:chemistry*; D011145:Polyvinyls / Q000737:chemistry*; D011485:Protein Binding
D020099:Coated Materials, Biocompatible; D005296:Ferrous Compounds; D011145:Polyvinyls; C451099:polyvinylferrocenium; D010984:Platinum; D005949:Glucose Oxidase; D005947:Glucose