Fabrication of a new polyaniline grafted multi-wall carbon nanotube modified electrode and its application for electrochemical detection of hydrogen peroxide

A modified electrode is fabricated by grafting polyaniline (PANI) chains onto multiwalled carbon nanotube (MWNT) for the detection of hydrogen peroxide (H2O2). PANI grafted MWNT modified electrode (PANI-g-MWNT-ME) displays excellent electrocatalytic response to the detection of H2O2 in a concentration range of (1.0–20) × 10−8 M showing linear response to current, with an extended lower detection limit down to 1 nM. This modified electrode exhibits an accelerated electron transfer at the interface with minimized surface fouling and surface renewability. Further, electrochemical analysis of H2O2 performed in the presence of common interferents such as uric acid, ascorbic acid and acetaminophen with the modified electrode reveals that there is no overlapping signal from the interferents. The combined presence of MWNT and PANI in the modified electrode provides high sensitivity and selectivity.