Sonodynamic therapy (SDT) represents a promising approach for cancer treatment. Compared to photodynamic therapy, SDT offers increased penetration depth and higher precision. However, the practical application of SDT is constrained by the low water solubility, poor tumor specificity, and metabolic susceptibility of most sonosensitizers. Recent research has explored the use of piezoelectric materials as sonosensitizers in cancer treatment and inhibition of bacterial growth. Upon ultrasound excitation, the separation of electron-hole (e--h+) pairs occurs within the piezoelectric material. By improving the crystal structure of the material or incorporating other nanoparticles to prevent rapid recombination of e--h+ pairs, the piezoelectric material accumulates charges in the conduction band and valence band, achieving the redox potential of O2/·O2 -. This enables the piezoelectric material to serve as a sonosensitizer, leading to the concept termed Sono-Piezo Dynamic Therapy (SPDT). This review aims to define the concept of SPDT, provide a systematic overview of the historical development of piezoelectric materials in the application of SDT, and elucidate the potential mechanisms by which piezoelectric materials act as sonosensitizers. Importantly, various piezoelectric materials will be discussed in terms of their feasibility, advantages, and disadvantages as sonosensitizers, offering new perspectives for identifying potential sonosensitizers.
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