Efficient Drug Delivery of Ti 3 C 2 T x MXenes for Synergistic Treatment of Human Hypopharyngeal Squamous Cell Carcinoma.

Ti 3 C 2 T x MXene is a versatile two-dimensional material that exhibits exceptional properties, such as an abundance of surface functional groups that facilitate modifications. Additionally, Ti 3 C 2 T x MXene possesses remarkable photothermal effects. In this study, ultrathin Ti 3 C 2 T x nanosheets with dimensions (∼200 nm) suitable for biological applications were prepared by ultrasonication of larger pieces of Ti 3 C 2 T x MXene with a cell pulverizer operating at a specific power. The ultrathin nanosheets exhibited a significant photothermal conversion efficiency (47.1%) under an 808 nm infrared laser irradiation. In addition, they showed an excellent mass extinction coefficient of 15.7 L g -1 cm -1 . By exploiting the intermolecular force between these ultrathin nanosheets and doxorubicin (DOX), a drug loading efficiency of 72.8% was achieved. Through layer-by-layer surface modification of a sulfhydryl-modified polymethacrylic acid (PMAsh) shell and a transferrin (Tf) layer with targeting function, a multifunctional nanomedicine platform (Ti 3 C 2 T x -DOX-PMAsh-Tf) was constructed. Experiments executed in vitro with cells and in vivo to inhibit tumors manifested that Ti 3 C 2 T x is biocompatible. Furthermore, the results showed that the drug release behavior of Ti 3 C 2 T x -DOX-PMAsh-Tf is responsive to glutathione (GSH) stimulation. The synergistic treatment of photothermal therapy and the anticancer drug DOX effectively achieved the inhibition of human hypopharyngeal squamous cell carcinoma.