Fig. 2

Photothermal properties, release profiles and biocompatibility of AHTPR NPs in vitro. a, b The infrared thermal images and time-dependent temperature elevation of AHTPR at various concentrations under 1.0 W cm⁻² 808 nm laser irradiation. c Time-dependent temperature change of AHTPR (120 µg mL⁻¹) under 808 nm laser irradiation with different laser power. d Photothermal stability curve of AHTPR (120 µg mL⁻¹) NPs following on/off NIR laser irradiation (2.0 W cm⁻²) for 5 cycles. e UV–vis spectra of AIBI, HTPR and AHTPR. f The UV–vis absorption spectra of AIBI with different concentrations. g The release profiles of AIBI from AHTPR in PBS with different pH values without or with NIR irradiation (808 nm, 1.0 W cm⁻², 10 min). h Cell viability of BMSCs after 24 h of treatments with various concentrations of AHTPR NPs. i Hemolysis assay of different concentrations of AHTPR samples