Construction and evaluation of tumor nucleus-targeting nanocomposite for cancer dual-mode imaging - Guiding photodynamic therapy/photothermal therapy.

To tackle the barrier of the insufficient intra-cellular delivery of reactive oxygen species (ROS) and heat, we designed a multifunctional nanoplatform to release ROS and heat directly in the cell nucleus for enhancing combined photodynamic therapy (PDT) and photothermal therapy (PTT) of tumors. As a photothermal agent, WS2 nanoparticles were adsorbed photosensitive Au25(Captopril)18- (Au25) nanoclusters via electrostatic interaction. And Dexamethasone (Dex), a glucocorticoid with nucleus targeting capability, played a key role in the intra-nuclear process of heat and ROS. PTT can increase intra-tumoral blood flow to promote Au25 produce more ROS for PDT. Under near infrared (NIR) laser irradiation at a single 808 nm, these nucleus targeting WS2 nanoplatforms showed a significant decreased cell viability of 18.2 ± 1.7% and a high DNA damage degree of 59.6 ± 8.3%. Furthermore, the WS2 nanoplatform could be further used for X-ray computed tomography (CT) images. Taken together, our study provided a new prospect for effectively diagnostic and enhancing PTT/PDT efficacy.