Fig. 2. (a) The EPR signals of DMPO for O₂⁻˙ characterization in the presence of 10 μM EBD-1 in CH₃OH at room temperature (808 nm laser; 200 mW cm⁻² for 60 s). (b) O₂⁻˙ detection in HeLa cells incubated with EBD-1 using DHE (10 μM, λ_ex = 488 nm, λ_em = 570–620 nm) under irradiation (808 nm laser; 200 mW cm⁻²). (c) OH˙ detection in HeLa cells incubated with EBD-1 using HPF (λ_ex = 488 nm, λ_em = 530 nm) under irradiation (808 nm laser; 200 mW cm⁻²) and the 3D imaging of OH˙ in HeLa cells by using HPF as an indicator after 10 min of laser irradiation (obtained using ImageJ). Scale bar = 20 μm.