Electrodeposited nanoscale zinc oxide particles: facilitating the electron transfer of immobilised protein and biosensing

The electron transfer of redox‐active sites of immobilised haemoglobin (Hb) has been studied by voltammetric experiments. The electrode surface was modified by nanoparticles (NPs) to make a suitable substrate for electric wiring of protein molecules and efficient electron transferring. Hence, the Hb/zinc oxide NPs/platinum electrode was prepared by chronoamperometric deposition of the NPs and immobilisation of protein molecules. The electrochemical behaviour of the prepared biosensor was quasi‐reversible and showed a pair of redox peaks with a formal potential ( E 0′ ) of 214 mV. Additionally, the electron transfer rate constant ( k s ) of immobilised Hb was about 0.621 s −1 . Biocatalytic reduction of hydrogen peroxide was also examined on the prepared biosensor. Result indicated to good sensitivity, wide linear range and low detection limit of 6 μM.