Luminescent CeO:Eu nanocrystals for robust in situ HO real-time detection in bacterial cell cultures.

Hydrogen peroxide (HO) quantification in biomedicine is valuable as inflammation biomarker but also in assays employing enzymes that generate or consume HO linked to a specific biomarker. Optical HO detection is typically performed through peroxidase-coupled reactions utilizing organic dyes that suffer, however, from poor stability/reproducibility and also cannot be employed in situ in dynamic complex cell cultures to monitor HO levels in real-time. Here, we utilize enzyme-mimetic CeO nanocrystals that are sensitive to HO and study the effect of HO presence on their electronic and luminescent properties.