AgBiS2 nanoparticles with synergistic photodynamic and bioimaging properties for enhanced malignant tumor phototherapy

Bismuth (Bi)-based nanoagents for synergistic photodynamic therapy (PDT) and photothermal therapy (PTT) are attracting attention and are highly desired for malignant tumor diagnosis and treatment, but producing these materials is still a challenge. Here, we designed theranostic nanoparticles (NPs) based on AgBiS2 for computed tomography (CT) imaging and phototherapy of malignant tumors. These AgBiS2 NPs could effectively convert light into heat (with a high photothermal conversion efficiency of 36.51%) and significantly increase the generation of intracellular reactive oxygen species (ROS) under near infrared (NIR) laser irradiation. Remarkably, the combined PTT/PDT successfully inhibited the growth of a highly malignant osteosarcoma in vivo. In addition, AgBiS2 NPs exhibited an enhanced CT contrast ability for tumor imaging and killed clinically derived Staphylococcus aureus (S. aureus) to prevent infection. In conclusion the ability of AgBiS2 NPs to be used in phototherapy and CT imaging and their antibacterial abilities indicate that they are promising candidates for malignant tumor theranostics.