In this work, the electrocatalytic oxidation of hydroxylamine on a glassy carbon electrode modified with oracet blue and multi-walled carbon nanotubes (OBMWCNT-GCE) has been studied. The peak potential of hydroxylamine at OBMWCNT-GCE surface shifts by about 320 and 335mV toward negative values compared with those at a MWCNT and activated GCE surface. Kinetic parameters for the oxidation of hydroxylamine at the modified electrode surface were determined by cyclic voltammetry measurements. The amperometric detection of hydroxylamine was carried out at 170 mV in a 0.1 mol L-1 phosphate buffer solution (pH 7.0) resulting in two linear response ranges of 4.0-102.4 µmol L-1 and 102.4-5820.9 µmol L-1 and the limit of detection of 0.7 µmol L-1. The amperometric response for hydroxylamine determination proved to be repeatable, fast and stable. Finally, OBMWCNT-GCE was successfully applied to the hydroxylamine determination in two water natural samples.
hydroxylamine; multi-walled carbon nanotubes; oracet blue; amperometry; electrocatalytic oxidation
