Multifunctional Two-Dimensional Core–Shell MXene@Gold Nanocomposites for Enhanced Photo–Radio Combined Therapy in the Second Biological Window

Abstract

Multifunctional nanoplatforms with special advantages in the diagnosis and treatment of cancer have been widely explored in nanomedicine. Herein, we synthesize two-dimensional core–shell nanocomposites (Ti3C2@Au) via a seed-growth method starting from the titanium carbide (Ti3C2) nanosheets, a classical type of MXene nanostructure. After growing gold on the surface of Ti3C2 nanosheets, the stability and biocompatibility of the nanocomposites are greatly improved by the thiol modification. Also importantly, the optical absorption in the near-infrared region is enhanced. Utilizing the ability of the high optical absorbance and strong X-ray attenuation, the synthesized Ti3C2@Au nanocomposites are used for photoacoustic and computed tomography dual-modal imaging. Importantly, the mild photothermal effect of the Ti3C2@Au nanocomposites could improve the tumor oxygenation, which significantly enhances the radiotherapy. No obvious long-term toxicity of the nanocomposites is found at the injected dose. This work highlights the promise of special properties of MXene-based multifunctional nanostructures for cancer theranostics.

2D Nanomaterials for Cancer Theranostic Applications

“…Ta 4 C 3 –IONP nanocomposite MXenes have also been demonstrated to be efficient breast‐cancer theranostics through bimodal CT/MR imaging‐guided PTT . Recently, our group also constructed multifunctional 2D Ti 3 C 2 @Au nanocomposites for bimodal‐imaging‐guided cancer therapy in the NIR‐II range . By growing Au on the surface of Ti 3 C 2 nanosheets, NIR‐II optical absorption in was greatly enhanced.…”

Second Near‐Infrared Absorbing Agents for Photoacoustic Imaging and Photothermal Therapy

“…2D titanium carbide (Ti 3 C 2 ) nanosheets coated with a gold shell to form Ti 3 C 2 @Au nanosheets was reported by Cheng and co‐workers for PA imaging–guided radiotherapy (RT) and NIR‐II PTT combinational therapy ( Figure a) . The NIR absorbance of Ti 3 C 2 @Au nanosheets increased with the rising of Au/Ti ratio (Figure b).…”

“…NIR irradiation was conducted by 1064 nm laser at 0.75 W cm −2 for 10 min, while the dose for RT was 6 Gy. Reproduced with permission . Copyright 2019, American Chemical Society.…”

Two-dimensional metal carbides and nitrides (MXenes): preparation, property, and applications in cancer therapy

“…Tang et al successfully prepared 2D core-shell Ti 3 C 2 @Au nanocomposites using the simple seed growth method [99]. Due to the growth of Au on the surface of Ti 3 C 2 , the stability of MXene was greatly improved by mercaptan chemistry, and the absorbance of nanocomposites in the window of NIR-I and NIR-II was significantly improved.…”

“…Ren et al developed (A) Tumor volume growth curves of mice after various treatments (n = 5). NIR irradiation was conducted by 1064 nm laser at 0.75 W cm −2 for 10 min, whereas the dose for RT was 6 Gy [99]. (B) Photographs of tumors harvested from mice 14 days after the treatments [99].…”