Subtractive Nanopore Engineered MXene Photonic Nanomedicine with Enhanced Capability of Photothermia and Drug Delivery for Synergistic Treatment of Osteosarcoma

Two-dimensional (2D) nanomaterials as drug carriers and photosensitizers have emerged as a promising antitumor strategy. However, our understanding of 2D antitumor nanomaterials is limited to intrinsic properties or additive modification of different materials. Subtractive structural engineering of 2D nanomaterials for better antitumor efficacy is largely overlooked. Here, subtractively engineered 2D MXenes with uniformly distributed nanopores are synthesized. The nanoporous defects endowed MXene with enhanced surface plasmon resonance effect for better optical absorbance performance and strong exciton-phonon coupling for higher photothermal conversion efficiency. In addition, porous structure improves the binding ability between drug and unsaturated bonds, thus promoting drug-loading capacity and reducing uncontrolled drug release. Furthermore, the porous structure provides adhesion sites for filopodia, thereby promoting the cellular internalization of the drug. Clinically, osteosarcoma is the most common bone malignancy routinely treated with doxorubicin-based chemotherapy. There have been no significant treatment advances in the past decade. As a proof-of-concept, nanoporous MXene loaded with doxorubicin is developed for treating human osteosarcoma cells. The porous MXene platform results in a higher amount of doxorubicin-loading, faster near-infrared (NIR)-controlled doxorubicin release, higher photothermal efficacy under NIR irradiation, and increased cell adhesion and internalization. This facile method pioneers a new paradigm for enhancing 2D material functions and is attractive for tumor treatment.