Fig. 2. Photothermal effect of OHH NPs . (A) Photothermal heating curve of water, HMPB, Ofloxacin and OHH NPs. (B) Infrared thermal images of different samples (0.1 mg/mL) irradiated with 808 nm light (1 W/cm2, 10 minutes). (C) The heating curve of OHH NPs under different power laser irradiation. (D) Temperature changes of different concentrations of OHH solution irradiated by 808 nm laser. (E) Photothermal effect of OHH NPs under 808 nm laser-on and then laser-off. Plot of linear time data versus −ln(θ), which was obtained from the cooling stage (F) Photostability of OHH NPs with 5 cycles.