Polydopamine-Modified 2D Iron (II) Immobilized MnPS 3 Nanosheets for Multimodal Imaging-Guided Cancer Synergistic Photothermal-Chemodynamic Therapy.

Manganese phosphosulphide (MnPS 3 ), a newly emerged and promising member of the 2D metal phosphorus trichalcogenides (MPX 3 ) family, has aroused abundant interest due to its unique physicochemical properties and applications in energy storage and conversion. However, its potential in the field of biomedicine, particularly as a nanotherapeutic platform for cancer therapy, has remained largely unexplored. Herein, a 2D "all-in-one" theranostic nanoplatform based on MnPS 3 is designed and applied for imaging-guided synergistic photothermal-chemodynamic therapy. (Iron) Fe (II) ions are immobilized on the surface of MnPS 3 nanosheets to facilitate effective chemodynamic therapy (CDT). Upon surface modification with polydopamine (PDA) and polyethylene glycol (PEG), the obtained Fe-MnPS 3 /PDA-PEG nanosheets exhibit exceptional photothermal conversion efficiency (η = 40.7%) and proficient pH/NIR-responsive Fenton catalytic activity, enabling efficient photothermal therapy (PTT) and CDT. Importantly, such nanoplatform can also serve as an efficient theranostic agent for multimodal imaging, facilitating real-time monitoring and guidance of the therapeutic process. After fulfilling the therapeutic functions, the Fe-MnPS 3 /PDA-PEG nanosheets can be efficiently excreted from the body, alleviating the concerns of long-term retention and potential toxicity. This work presents an effective, precise, and safe 2D "all-in-one" theranostic nanoplatform based on MnPS 3 for high-efficiency tumor-specific theranostics.