Abstract
A novel mechanism to detect hydrogen peroxide (H2O2) using a poly(N-butyl benzimidazole) (PBBI)-modified gold (PBBI/Au) electrode is proposed. Synthetic PBBI was oxidized using a mixture of acetic acid (AcOH) and H2O2 to form PBBI N-oxide (PBBINO). The structure of PBBINO was verified by Fourier transform infrared spectroscopy (FT-IR) and the degree of oxidation was measured by X-ray photoelectron spectroscopy (XPS). Moreover, the oxide could be reduced electrochemically back to PBBI. Based on this reaction, a novel enzyme-free PBBI/Au electrode was developed to detect H2O2 in the presence of AcOH electrochemically. The biosensor detected H2O2 linearly over concentrations ranging from 25μM to 10mM with a detection limit of 6.25μM in phosphate buffer solution (PBS) mixed with AcOH at pH 6.4. In addition, at an applied potential of -0.5V, the sensor characteristics could be tuned using AcOH over a pH range of 3.7-6.4. The sensitivity of the probe could be enhanced from 35.1 to 419.4μAmM-1cm-2 by modifying the surface morphology of the PBBI/Au electrode from a smooth plane to a granular, three-dimensional configuration. Furthermore, it was not influenced by interfering compounds and showed high thermal stability.
Original language | English |
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Pages (from-to) | 114-120 |
Number of pages | 7 |
Journal | Analytica Chimica Acta |
Volume | 693 |
Issue number | 1-2 |
DOIs | |
State | Published - 05 05 2011 |
Keywords
- Biosensor
- Hydrogen peroxide
- Peracetic acid
- Poly(N-butyl benzimidazole)
- Poly(N-butyl benzimidazole) N-oxide