Direct spectroelectrochemistry of peroxidases immobilised on mesoporous metal oxide electrodes: Towards reagentless hydrogen peroxide sensing

In this paper, we employ two peroxidases (horseradish peroxidase, HRP and cytochrome c peroxidase, CcP) to demonstrate their ability to retain their redox and biological functions after their immobilisation on mesoporous TiO2 and SnO2 electrodes. We will also demonstrate the use of HRP immobilised on the metal oxide electrodes for the development of reagentless optical and electrochemical biosensors for the detection of hydrogen peroxide (H2O2) with low detection limit of 0.04 and 1 μM, respectively.