CdSe nanocrystals as hydroperoxide scavengers: A new approach to highly sensitive quantification of lipid hydroperoxides

The CdSe nanocrystals (NCs), which have been widely employed for bioimaging, biosensing, and for quantifying inorganic anion and metal cations, and DNA detection, can also be used as good hydroperoxide scavengers. CdSe NCS are highly sensitive to hydroperoxides, so these NCs can be applied to monitor hydroperoxide generation and dynamics in living organisms. It was observed that the fluorescence quenching of CdSe NCs by hydroperoxide does not display a direct linear relationship between hydroperoxide concentration and CdSe NC concentration. Partial oxidation of surface Se atoms can decrease the quantum yield of the same NC but does not lead to complete quenching of its fluorescence. This excellent linearity makes the quantification of CdSe NCs in hydrogen peroxide or lipid peroxide possible. Fluorescent probes that re sensitive to hydroperoxide can provide a new means to better understanding oxidative stress, and signal transduction by hydroperoxides and NCs have great potential.