Controlled preparation and photothermal properties of polydopamine submicrospheres

Polydopamine (PDA) as a good photothermal reagent can efficiently convert photon energy into heat energy, which can kill cancer cells by heating dissipation in targeted tumors. In this experiment, PDA submicrospheres were prepared by using dopamine hydrochloride as the reaction raw material, anhydrous ethanol and ultrapure water as the reaction solvent. Diethanolamine provided an alkaline reaction environment. By controlling the solvent composition ratio, submicrospheres with diameters ranging from 120 to 300 nm can be obtained. The water solution containing the PDA submicrospheres rapidly increased to 48 °C in 10 min with 1 W/cm2 power density and 980 nm near-infrared (NIR) light. PDA submicrospheres may have potential application in photothermal treatment.