2D MBene Nanosheets as Sonosensitizers for Ultrasound-Triggered Precision Cancer Therapy

Sonodynamic therapy, as a deep penetrating therapy method with high therapy efficacy, is garnering attention in the field of tumor therapy. Nevertheless, the trade-off between high sonodynamic efficacy and stability is difficult to balance for conventional sonosensitizers, which impedes their clinical translation. Exploring the sonodynamic performance of novel materials is imperative to synchronously achieve these two aims. Two-dimensional (2D) metal borides (MBene) possess enormous application potential in biotechnology fields, but so far there are few studies on sonodynamic therapy research. In this work, two types of metal boride nanosheets, orthorhombic and hexagonal molybdenum boride (MoAlB-MoB and Mo 4/3 B 2-x T z ), are synthesized, and their properties are characterized to understand the structure-properties relationship. The MBene nanosheets demonstrate superior and stable sonodynamic efficacy compared with commercial sonosensitizers (TiO 2 and indocyanine green) and a nanosheet sonosensitizer (Mo 2 C MXene). By delivering via microneedle, the MBene nanosheets can significantly inhibit tumor growth with a high precision through sonodynamic reactions. Mechanistic investigations reveal that immunity is activated and long-term immunity memory is established to suppress tumor. The structure-function relationship of MBene nanosheets are further simulated. This work elucidates the therapeutic potential and mechanistic foundations of MBene-based sonodynamic therapy, establishing a promising platform for sonodynamic cancer therapy.