Co₃O₄-cored carbon dots for chemiluminescence analysis of intracellular hydrogen peroxide

Co₃O₄-cored carbon dots were prepared to induce chemiluminescence from the carbon dots in the presence of hydrogen peroxide at neutral pH. Neither a strong oxidative agent nor alkaline was needed as a co-reactant, which permitted for the first time the application of CDs for such chemiluminescence analysis of cells. The detection limit of hydrogen peroxide was determined to be 10 μM. Due to their good cellular permeability and low cytotoxicity, these nanoparticles were loaded into cells. The greater luminescence observed in cells with elevated intracellular hydrogen peroxide levels showed that our probe could measure the change in concentration of hydrogen peroxide inside cells.