3. Conclusions
In summary, an 880 nm NIR laser triggered TNPs as PTA for photothermal therapy of tumor in deep tissue was developed. In this work, a novel PTA, 3TT-IC-4Cl, was selected and used for PTT, it includes three fused thieno[3,2-b]thiophene as the central core and difluoro substituted indanone as the end groups, after encapsulation by FA-PEG-PBLA10 block copolymer and forming nanoparticles, the TNPs aqueous solution exhibit strong absorption at 880 nm due to the π-π stacking. DLS and TEM measurements showed that the TNPs have spherical shape and narrow size distribution with a mean diameter of 150 nm. These stable nanoparticles are suitable for the EPR effect and accumulation in the tumor tissue. TNPs exhibit excellent photothermal stability and high photothermal conversion efficiency after 880 nm laser irradiation. In the in vitro test, TNPs display excellent biocompatibility and significant phototoxicity. Therefore, the 880 nm triggered TNPs has great potential as an effective PTAs for photothermal therapy of tumor in deep tissue.