Near-infrared (NIR)-absorbing
metal-based nanomaterials have shown tremendous potential for
cancer therapy, given their facile and controllable synthesis, efficient photothermal conversion, capability of spatiotemporal-controlled
drug delivery, and intrinsic imaging function.
Tantalum (Ta) is among the most biocompatible metals and arouses negligible adverse
biological responses in either oxidized or reduced forms, and thus Ta-derived nanomaterials represent promising candidates for biomedical applications. However, Ta-based nanomaterials by themselves have not been explored for NIR-mediated photothermal ablation
therapy. In this work, we report an innovative Ta-based multifunctional nanoplatform composed of biocompatible
tantalum sulfide (TaS2) nanosheets (NSs) for simultaneous NIR
hyperthermia,
drug delivery, and computed tomography (CT) imaging. The TaS2 NSs exhibit multiple unique features including (i) efficient NIR light-to-heat conversion with a high photothermal conversion efficiency of 39%. (ii) high
drug loading (177% by weight), (iii) controlled drug release triggered by NIR light and moderate acidic pH, (iv) high
tumor accumulation via heat-enhanced
tumor vascular permeability, (v) complete
tumor ablation and negligible side effects, and (vi) comparable CT imaging contrast efficiency to the widely clinically used agent
iobitridol. We expect that this multifunctional NS platform can serve as a promising candidate for imaging-guided
cancer therapy and selection of
cancer patients with high
tumor accumulation.