Glucose Biosensor Based on Multi‐Walled Carbon Nanotube Modified Glassy Carbon Electrode

Abstract

An amperometric glucose biosensor based on multi-walled carbon nanotube (MWCNT) modified glassy carbon electrode has been developed. MWCNT-modified glassy carbon electrode was obtained by casting the electrode surface with multi-walled carbon nanotube materials. Glucose oxidase was co-immobilized on the MWCNT-modified glassy carbon surface by electrochemical deposition of poly(o-phenylenediamine) film. Enhanced catalytic electroreduction behavior of oxygen at MWCNT-modified electrode surface was observed at a potential of À 0.40 V (vs. Ag j AgCl) in neutral medium. The steady-state amperometric response to glucose was determined at a selected potential of À 0.30 V by means of the reduction of dissolved oxygen consumed by the enzymatic reaction. Common interferents such as ascorbic acid, 4-acetamidophenol, and uric acid did not interfere in the glucose determination. The linear range for glucose determination extended to 2.0 mM and the detection limit was estimated to be about 0.03 mM.

Conductive Mesocellular Silica–Carbon Nanocomposite Foams for Immobilization, Direct Electrochemistry, and Biosensing of Proteins

“…The time required for reaching 95 % of the steady-state response is less than 4 s. The linear calibration range for glucose is 0.05-5.0 mM (r = 0.999, n = 11) with a detection limit of 35 lM. The linear range of up to 5.0 mM is comparable to that observed for the electrocatalytic reduction of dissolved oxygen by MWCNTs, [31] is larger than the 2 mM limit for oxygen-sensitive glucose biosensors, [32,33] and is indeed much larger than the 0.28 mM value based on the same mechanism for gold-nanoparticle-modified electrodes. [25] Such an extended linear range arises from the increased oxygen content around the immobilized GOD due to the large surface area and mesoporous volume of the MSCF.…”

“…The amperometric response of the MSCF/GOD/Nafionmodified electrode to glucose starts at a potential of -0.25 V and reaches its maximum value at -0.4 V; the latter value has been used here for the amperometric detection of glucose. This applied potential appears to be more negative than those based on the consumption of dissolved oxygen, [31,32] such as carbon nanotubes immobilized on electrodes, which electrocatalytically reduce dissolved oxygen.…”

A Mediator‐Free Bienzyme Amperometric Biosensor Based on Horseradish Peroxidase and Glucose Oxidase Immobilized on Carbon Nanotube Modified Electrode

“…), higher than the mono-enzyme biosensor [12,32]. The detection limit was estimated to be about 0.5 mM for a signal-to-noise of 3.…”

“…Incorporation of redox proteins and enzymes on CNT-modified electrodes exhibited superior performance for the good electronic communication between CNT and the proteins/ enzymes. Cytochrome c [10], horseradish peroxidase [11] and glucose oxidase [12] adsorbed on carbon nanotubes showed good electrochemical properties. Direct electrochemistry of redox enzymes at electrodes incorporated with novel materials has also been explored [13 -14].…”

Electroanalytical Applications Based on Carbon Nanotube/Prussian Blue Screen-printable Composite

“…Some authors 6,7 have widely reviewed the ability of CNTs to promote electron transfer reactions regarding different biomolecules and their biosensing applications such as Pt nanoparticles and CNT composite, 8 modification of glassy carbon electrodes with CNT, 9 and a binder-less composite CNT/graphite/enzyme mixture packed in a needle. 10 Several methods have also been proposed for the immobilization of CNTs on electrochemical transducer like the CNT/epoxy composites, 11 formulation of CNT/Teflon composite, 12,13 CNT/Nafion association 14 and CNT/chitosan system 15 because they are not readily dispersed in aqueous medium.…”