Ultrasmall PEI-Decorated Bi(2)Se(3) Nanodots as a Multifunctional Theranostic Nanoplatform for in vivo CT Imaging-Guided Cancer Photothermal Therapy

Bi-based nanomaterials, such as Bi(2)Se(3), play an important part in biomedicine, such as photothermal therapy (PTT) and computed tomography (CT) imaging. Polyethylenimine (PEI)-modified ultrasmall Bi(2)Se(3) nanodots were prepared using an ultrafast synthetic method at room temperature (25°C). Bi(2)Se(3) nanodots exhibited superior CT imaging performance, and could be used as effective photothermal reagents owing to their broad absorption in the ultraviolet–visible–near infrared region. Under irradiation at 808 nm, PEI-Bi(2)Se(3) nanodots exhibited excellent photothermal-conversion efficiency of up to 41.3%. Good biocompatibility and significant tumor-ablation capabilities were demonstrated in vitro and in vivo. These results revealed that PEI-Bi(2)Se(3) nanodots are safe and a good nanotheranostic platform for CT imaging-guided PTT of cancer.