Photoelectronic properties of horseradish peroxidase-functionalized CdSe/silica mesoporous composite and its sensing towards hydrogen peroxide

CdSe nanocrystals were prepared within a template of mesoporous silica (MS) spheres via chemical reaction, and then the as-synthesized CdSe/MS composites were dip coated on an optically transparent electrode. The photoelectric properties of CdSe/MS composite film were examined under ultraviolet (UV) illumination at the excitation wavelength of 365 nm. The CdSe/MS composite can facilitate charge rectification and minimize charge recombination as shown by its higher photocurrent. Most importantly, horseradish peroxidase (HRP)-functionalized CdSe/MS-modified electrode (HRP/CdSe/MS) had a stronger response toward hydrogen peroxide (H2O2) under UV illumination than in the dark. The result demonstrates the potential application of HRP/CdSe/MS composite film as a novel biosensor for monitoring H2O2 under UV illumination.