Evaluation of nafion as media for glucose oxidase immobilization for the development of an amperometric glucose biosensor

Abstract

A novel glucose biosensor has been prepared by deposition of a mixture containing glucose oxidase dissolved in water and Nafion dissolved in methanol at the surface of a platinum disk electrode. Glucuse concentration is evaluated by measuring the amperometric current corresponding to hydrogen peroxide electrooxidation at 0.7 iJ vs. SCE. The addition of glucose oxidase to Nafion resulted in a Nafion-glucose oxidase film that was more permeable to anionic species than Nafion alone. The calibration curve for glucose is linear from 5 p M u p to about 10 mM. Tn oxygen-saturated solution, the linear range extended to 15 mM. The optimum pH for the assay was found to be 5.5. The enzyme is not stabilized against temperature deactivation when it is immobilized in Nafion. The Pt/Nafion-glucose oxidase electrodes showed good stability when stored dry at room temperature with 80% of the initial response retained after 250 days.

Highly efficient potentiometric glucose biosensor based on functionalized InN quantum dots

“…Upon the addition of 50 lM ascorbic acid or uric acid to 500 lM glucose solution the output (EMF) signal does not substantially change, as shown in Figure 5(a). This reveals that the presented biosensor has good selectivity which is attributed to the perm selective (charge-exclusion) property 18,19 of the Nafion film coated on the sensing electrode.…”

Functionalised zinc oxide nanotube arrays as electrochemical sensors for the selective determination of glucose

“…5. We suggest that the good selectivity of the present biosensor can be attributed to the permselective (charge-exclusion) property [43][44] of Nafion films coated on the electrode. The proposed…”

Carbon Nanotube-Based Cholinesterase Biosensors for the Detection of Pesticides

“…The suspension of CNTs in cetyltrimethylammonium bromide (CTAB) aqueous solution was also reported (Cai and Chen, 2004). Nafion has been used extensively for the modification of electrode surfaces and for the construction of amperometric biosensors because of the unique ion-exchange, discriminative, and biocompatibility properties (Fortier et al, 1992;Fan et al, 1992). Nafion contains two different regions: the hydrophobic polymer backbone and the ionized hydrophilic sulfonate groups outside the hydrophobic region.…”