A one-pot synthesis of multifunctional BiS nanoparticles and the construction of core-shell BiS@Ce6-CeO nanocomposites for NIR-triggered phototherapy.

As a direct thin band gap n-type semiconductor, bismuth sulfide (Bi2S3) nanomaterials possess great near-infrared (NIR)-triggered photothermal effects, photoacoustic (PA) and computed tomography (CT) imaging properties. Hence, Bi2S3 nanomaterials have become a research focal point in multiple domains, such as the construction of NIR-triggered nanosystems for cancer therapy. In this study, through a simple one-pot synthesis with the assistance of EDTA-2Na, we first obtained monodispersed spherical Bi2S3 of uniform particle sizes with fascinating photothermal and PA/CT imaging properties. Based on this, we introduced the photosensitizer Ce6 with photodynamic property and CeO2 with the O2-evolving characteristic, and thus designed a core-shell structure of the Bi2S3@Ce6-CeO2 nanocomposites (Bi2S3@Ce6-CeO2 NCs). The as-received Bi2S3@Ce6-CeO2 NCs exhibited a remarkable synergetic photothermal and photodynamic therapeutic effect both in vitro and in vivo, demonstrating its promising potential for cancer treatments. In the long term, the multifunctional PA/CT properties of both Bi2S3 NPs and Bi2S3@Ce6-CeO2 NCs in this study also supply a novel Bi2S3-based platform for constructing integrated diagnosis and treatment platforms.