A non-enzymatic sensor for hydrogen peroxide based on polyaniline, multiwalled carbon nanotubes and gold nanoparticles modified Au electrode

We describe the construction of a polyaniline (PANI), multiwalled carbon nanotubes (MWCNTs) and gold nanoparticles (AuNPs) modified Au electrode for determination of hydrogen peroxide without using peroxidase (HRP). The AuNPs/MWCNT/PANI composite film deposited on Au electrode was characterized by Scanning Electron Microscopy (SEM) and electrochemical methods. Cyclic voltammetric (CV) studies of the electrode at different stages of construction demonstrated that the modified electrode had enhanced electrochemical oxidation of H2O2, which offers a number of attractive features to develop amperometric sensors based on split of H2O2. The amperometric response to H2O2 showed a linear relationship in the range from 3.0 mu M to 600.0 mu M with a detection limit of 0.3 mu M (S/N = 3) and with high sensitivity of 3.3 mA mu M-1. The sensor gave accurate and satisfactory results, when employed for determination of H2O2 in milk and urine.