Enhanced Cancer Imaging and Chemo‐Photothermal Combination Therapy by Cancer‐Targeting Bismuth‐Based Nanoparticles

Abstract Due to the complexity and heterogeneity of cancer, the clear and accurate tumor imaging and image‐guided multimodal synergistic therapy are highly in demand. Here, bismuth (Bi)‐based mesoporous‐silica‐coated nanoparticles (BMSNs) are successfully fabricated with the silica shell thickness being lower than the Bi nanoparticle diameter. Then, an MCF‐7 breast cancer‐targeting peptide (termed AR) is modified onto the surface of BMSNs. The obtained nanoparticles (BMSN‐AR) show a significantly higher loading of doxorubicin hydrochloride (DOX). The resultant BMSN‐AR‐DOX can agglomerate in the tumor site, enabling enhanced computed tomography (CT) imaging of the whole tumor. Under 808 nm near‐infrared (NIR) laser irradiation, the BMSN‐AR‐DOX also effectively converts light energy into thermal energy to achieve synergistic chemo‐photothermal therapy in vivo. The chemo‐photothermal combination therapy is found to be more effective than chemotherapy or photothermal therapy alone. This work demonstrates that tumor‐homing peptides can guide nanoparticles to tumors and allow the nanoparticles to enhance cancer imaging and photothermal/chemo combination therapy.