Renal-Clearable Hollow Bismuth Subcarbonate Nanotubes for Tumor Targeted Computed Tomography Imaging and Chemoradiotherapy

Although metallic nanomaterials with high X-ray attenuation coefficients have been widely used as X-ray computed tomography (CT) contrast agents, their intrinsically poor biodegradability requires them to be cleared from the body to avoid any potential toxicity. On the other hand, extremely small-sized nanomaterials with outstanding renal clearance properties are not much effective for tumor targeting because of their too rapid clearance in vivo. To overcome this dilemma, here we report on the hollow bismuth subcarbonate nanotubes (BNTs) assembled from renal-clearable ultrasmall bismuth subcarbonate nanoclusters for tumor-targeted imaging and chemoradiotherapy. The BNTs could be targeted to tumors with high efficiency and exhibit a high CT contrast effect. Moreover, simultaneous radio- and chemotherapy using drug-loaded BNTs could significantly suppress tumor volumes, highlighting their …