Designed formation of Prussian Blue/CuS Janus nanostructure with enhanced NIR-I and NIR-II dual window response for tumor thermotherapy

Designing photothermal transducing agents (PTAs) with enhanced photothermal conversion efficiency (PCE) holds essential importance for photothermal tumor eradication applications. Currently, it is an effective way to improve the photothermal efficiency by designing the energy level transition leading to the enhancement of UV absorption. To address the challenge, we develop novel Prussian blue@polyacrylic acid/copper sulfide Janus nanoparticles (PB@PAA/CuS JNPs) via selective coating of PAA nano-hemisphere on one of the surfaces of PB NPs followed by the further formation of CuS on the PAA template. The experiments show that the energy level transition occurs between Janus structure. Besides, it offers enhanced absorption over NIR-I and NIR-II dual windows. The muscle tissue penetration studies suggest that the PB@PAA/CuS JNPs have deeper tissue penetration in the 1064 nm laser irradiation group, indicating their potential for treating deep-tissue-seated tumors. In a word, the unique PB@PAA/CuS JNPs show an enhanced tumor inhibitory effect over the NIR-I and NIR-II dual windows, which will open up new opportunities for improving PTT efficiency by the rational nanostructural design of PTAs.