Bienzyme based biosensing platform using functionalized carbon nanotubes.
This work presents a novel approach to design an amperometric transducer capable of detecting glucose and hydrogen peroxide. The biosensor is based on a bienzyme-channelling configuration, employing the enzymes glucose oxidase and horseradish peroxidase, which were immobilized with Toluidine blue (TB) functionalized multiwalled carbon nanotubes (MWNTs). TB was covalently immobilized with carboxylic acid groups of the carbon nanotubes via carbodiimide reaction. The MWNT/TB/GOD/HRP/Nf nanobiocomposite was prepared by mixing the GOx and HRP solution with TB functionalized CNTs followed by mixing homogeneously with Nafion. The MWNTiTB/GOD/HRP/Nf nanobiocomposite was characterized by scanning electron microscopy. The performance of the MWNT/TB/GOD/HRP/Nf nanobiocomposite modified electrode was examined by electrochemical impedance spectroscopy and cyclic voltammetry. Linear calibrations were achieved upto 1.4 x 10(-7)-1.6 x 10(-3) M for glucose and 6.8 x 10(-8)-1.7 x 10(-3) M for H2O2. A remarkable feature of this bienzyme electrode is the possibility to detect glucose and H2O2 at very low applied potentials where the noise level and interferences from other electro-active compounds are minimal.
Jeykumari
D R Shobha
DR
Department of Analytical Chemistry, School of Chemical Sciences, University of Madras, Guindy Campus, Chennai 600025, India.
Narayanan
S Sriman
SS
D015374:Biosensing Techniques; D004563:Electrochemistry; D005949:Glucose Oxidase / Q000737:chemistry; D006735:Horseradish Peroxidase / Q000737:chemistry; D006861:Hydrogen Peroxide; D037742:Nanotubes, Carbon / Q000737:chemistry
D037742:Nanotubes, Carbon; D006861:Hydrogen Peroxide; D005949:Glucose Oxidase; D006735:Horseradish Peroxidase