Single-molecule detection of reactive oxygen species: application to photocatalytic reactions.

In this review, we have focused on the oxidation reactions of single dye molecules by reactive oxygen species (ROS). The methodologies for the single-molecule detection of ROS, such as hydroxyl radical (HO*), singlet oxygen (O(2)(a(1)Delta(g))), and hydrogen peroxide (H2O2), have been introduced together with examples. In particular, a successful application using the single-molecule fluorescence technique for the investigation of the TiO2 photocatalytic oxidation reactions is demonstrated in detail.