Figure 4.

(A) The scheme of pH/NIR-II responded drug release and heat generation. (B) Photothermal heating curves of IR-AFN@PTX-FA solution at different concentrations under 5 min of 1064 nm laser irradiation (0.75 W/cm²). (C) Photothermal heating curves and (D) thermal images of 200 ug/ml of IR-AFN@PTX-FA solution irradiated by different laser power density (under 5 min of 1064 nm laser irradiation). (E) Temperature variations (ΔT) of IR-AFN@PTX-FA after the continuous irradiations of 5 min of 1064 nm laser for 5 cycles. (F) Release kinetics of PTX from IR-AFN@PTX-FA in PBS buffer (pH = 7.4 and 5.0) with or without 1064 nm laser irradiation (0.75 W/cm²).

Abbreviations: IR, IR1061; AFN, apoferritin; PTX, paclitaxel; FA, folic acid; NIR-II, second near infrared; PBS, phosphate buffer solution.