Simultaneous Determination of Nitrite and Hydrogen Peroxide Using Hemoglobin Modified Pencil Lead Electrode as a Novel Biosensor: Application to the Analysis of Mother’s Milk

In the present paper simultaneous determination of nitrite and hydrogen peroxide using hemoglobin modified pencil lead electrode (Hb/PLE) prepared by a simple and rapid electroless method was described. In the first part of the work the reduction of NO2 and H2O2 at the modified electrode was investigated by cyclic voltammetry. Then under optimal conditions using differential pulse voltammetry, the biosensor could be used for the determination of H2O2 at concentration ranging from 5 to 240 M and NO2 at concentration ranging from 10 to 240 M. The detection limits were 3×10−6 and 5×10−6 M, for NO2 and H2O2 respectively. Differential pulse voltammetry also used for the simultaneous determination of NO2 and H2O2. This modified electrode successfully used for the determination of NO2 and H2O2 in tap water and mother’s milk samples.