Near-Infrared Multifunctional Antitumor Nanomaterial of Bismuth Sulfide Heterojunction Coupled with Mesoporous Polydopamine

Bismuth sulfide@bismuth nanorods (Bi₂S₃@Bi NRs) have emerged as promising photodynamic therapeutic agents due to Bi₂S₃@Bi being able to produce reactive oxygen species from self-supplied O₂. Combining photothermal and photodynamic therapies with chemotherapy is attractive but difficult to achieve. Here, we develop a subtle method to wrap Bi₂S₃@Bi NRs with photothermal mesoporous polydopamine, where chemotherapy drug doxorubicin hydrochloride can be loaded, thus providing multifunctional antitumor nanospheres. To our delight, the prepared triple-functional material exhibits excellent antitumor efficacy toward tumor cells under near-infrared light irradiation. This multifunctional antitumor nanomaterial is not only biocompatible but also suitable for tumor hypoxic microenvironments, having much better efficacy than single- or double-functional materials. This study highlights the great potential of combining photothermal, photodynamic, and chemotherapies.