Hydrogen peroxide residue determination in food samples by a glassy carbon electrode modified with CuO-SWCNT-PDDA nanocomposites

Copper oxide-single walled carbon nanotube (CuO-SWCNT) hybrid nanostructure and poly-(diallyldimethylammonium chloride) (PDDA) modified glassy carbon electrode (GCE) for sensitive enzyme-free H 2 O 2 detection has been fabricated via electrostatic interaction strategies. Characterization by XRD, IR and SEM showing that CuO was coated on SWCNT molecular wires, and positively charged PDDA attached to the negatively charged SWCNT, thus CuO-SWCNT-PDDA was constructed. The reduction peak current of H 2 O 2 was significantly increased due to the catalytic property of CuO, which was further enhanced by the synergic effect of SWCNT due to its improvement of electron transfer rate. The calibration curve was linear in the range of 1–1150 µM with a detection limit of 0.39 µM. The electrode coupled with amperometric measurement was successfully applied in H 2 O 2 residue determination in milk and the soaking solutions of chicken paw samples. The results have no remarkable difference compared with the reference UV–Vis method.