Title of article :
Direct electrochemistry of cytochrome c and biosensing for hydrogen peroxide on polyaniline grafted multi-walled carbon nanotube electrode
Author/Authors :
Lee، نويسنده , , Kwang-Pill and Gopalan، نويسنده , , Anantha Iyengar and Komathi، نويسنده , , Shanmugasundaram، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2009
Pages :
8
From page :
518
To page :
525
Abstract :
Cytochrome c (cyt c) was immobilized into a matrix consisting of polyaniline (PANI) and multi-walled carbon nanotubes (MWNT) by a new strategy. First, PANI chains were grafted onto MWNT through electropolymerization. Second, the amine groups in PANI chains were oxidized at an applied potential of +0.80 V to acquire positive charges that would effectively immobilize negatively charged cyt C. The ITO/MWNT-g-PANI(O)/cyt c electrode exhibited a pair of redox peaks with a peak potential separation (anodic to cathodic) of 0.25 V (vs Ag/AgCl) in 0.1 M phosphate buffer (pH 7.0). The results demonstrated that ITO/MWNT-g-PANI(O)/cyt c promoted direct electron transfer between cyt c and electrode with a high electron transfer rate constant (17 s−1). The ITO/MWNT-g-PANI(O)/cyt c electrode catalyzes the reduction of H2O2. The ITO/MWNT-g-PANI(O)/cyt c biosensor displays an amperometric response to H2O2 with a linear concentration range from 0.5 μM to 1.5 mM (r = 0.99, n = 12), a high sensitivity (32.2 μAm M−1) and fast response (9 s) and detection limit of 0.3 μM (S/N = 3).
Keywords :
cytochrome c , Direct electron transfer , Hydrogen peroxide , Grafted polyaniline , multi-walled carbon nanotube
Journal title :
Sensors and Actuators B: Chemical
Serial Year :
2009
Journal title :
Sensors and Actuators B: Chemical
Record number :
1437706
Link To Document :
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