Functionalized CuBiS nanoparticles for dual-modal imaging and targeted photothermal/photodynamic therapy.

Multifunctional nano-biomaterials with the integration of diagnostic and therapeutic functions have shown great promise in improving the efficacy of cancer therapy. Herein, a new nanoplatform based on functionalized CuBiS nanoparticles (NPs) is fabricated for tumour-targeted combination phototherapy. The as-synthesized hydrophobic CuBiS NPs are modified with DSPE-PEG/DSPE-PEG-NH, followed by the conjugation of the photosensitizer chlorin e6 (Ce6) and the target ligand folic acid (FA). The introduced Ce6 can further form a chelate complex with Gd. The rationally designed CuBiS-PEG-(Ce6-Gd)-FA NPs, which have high physiological stability and good biocompatibility, can specifically target FA-receptor over-expressed tumour cells. The CuBiS-PEG-(Ce6-Gd)-FA NPs exhibit effective dual-modal CT and MR imaging in the xenografted HeLa tumours. Importantly, excellent in vivo anti-tumour effects have been achieved by synergistic photothermal/photodynamic therapy using the multifunctional NPs. We expect that this versatile nanoplatform will play a role in exploring precise cancer diagnosis and therapy.