Study on the photothermal performance of supra-(carbon nanodots) developed with dicyandiamide N-doped

In the present work, the dicyandiamide N-doped supra-CNDs were synthesized just within 24 h. The supra-CNDs exhibited a new strong absorption band at longer wavelengths (450–900 nm) and higher photothermal conversion efficiency (55.49 % and 46.02 % irradiation at 730 nm and 808 nm, respectively). The supra-CNDs can still maintain excellent photothermal stability and reusability after three on/off cycles. The survival rate of cancer cells incubated with supra-CNDs was above 90 %, but the value was drastically reduced to 4.24 % and 7.25 % after strong photothermal ablation at 730 nm and 808 nm, respectively. The cell killing ability of the supra-CNDs was also validated by photothermal ablation experiment. The excellent photothermal performance and low toxicity make the supra-CNDs highly promising application in photothermal therapy.