Figure 2.

a) Time‐dependent temperature increase of UCTTD solution under NIR laser irradiation with various power intensity (0.1, 0.3, 0.5, 0.7 or 0.9 W cm⁻²) and b) different concentrations of UCTTD (0, 150, 300, 600, 900 or 1200 µg mL⁻¹) irradiated identical laser power (0.5 W cm⁻²). c) Photothermal stability of UCTTD solution (1.2 mg mL⁻¹) upon 10 min laser irradiation (0.5 W cm⁻²) and 10 min cooling for six on/off cycles. d) Irradiation‐cooling curve of UCTTD solution irradiated with an 808 nm laser at 0.5 W cm⁻², and the linear fit of time/−ln (θ) gained from the cooling process. e) The loading mass curve of PC4 at the concentrations of 25, 50, 100, 150 or 200 µg mL⁻¹ to the UCTTD. f) The release behavior of PC4 from the UCTTD in pH 7.4, 6.5, 6.0, and 5.5 PBS measured by the UV–vis spectrometer.