| Authors | Hossain Ali Rafiee Pour, Hassan Shafiey, Hedayatollah Ghourchian |
|---|---|
| Journal | Analytical and Bioanalytical Electrochemistry |
| Page number | 126-141 |
| Serial number | 3 |
| Volume number | 1 |
| Paper Type | Full Paper |
| Published At | 2009 |
| Journal Grade | ISI |
| Journal Type | Typographic |
| Journal Country | Iran, Islamic Republic Of |
Abstract
Cytochrome c (Cyt c) was absorbed on gold electrode modified with a
mixture (1:3) of 11-mercapto-1-undecanol and 11-mercaptoundecanoic acid (C11)
solutions. The Cyt c/C11/Au electrode thus prepared showed a well-defined quasi
reversible voltammetric peak with electron transfer rate constant of 234 s-1. The surface
coverage of Cyt c oriented on the surface of C11-modified electrode was determined to
be 4.73×10-11 mol cm-2. The Cyt c/C11/Au electrode linearly responded to H2O2 in the
concentration range from 90 to 500 μM with a correlation coefficient of 0.9973. Using
the reciprocal plot of the steady state current versus hydrogen peroxide concentration,
apparent Michaelis constant for the Cyt c was estimated to be 759 μM. In addition,
voltammetric analysis was used to study the in situ denaturation of the immobilized Cyt
c by gradual addition of either urea up to 8 M or dimethyl formamide (DMF) up to 55%.
It was revealed that the mechanism of Cyt c denaturation depends on media (organic or
aqueous) were used. So that in the presence of DMF it follows a two-phase process,
whereas in urea containing buffer solution, it pursues a single-phase course.