The generally undesirable bandgap and electron–hole complexation of inorganic sonosensitizers limit the efficiency of reactive oxygen species (ROS) generation, affecting the effectiveness of sonodynamic therapy (SDT). Comparatively, the novel polyvinylpyrrolidone‐modified copper bismuthate (PCBO) sonosensitizers are manufactured for a “three‐step” SDT promotion. In brief, first, the strong hybridization between Bi 6s and O 2p orbitals in PCBO narrows the bandgap (1.83 eV), facilitating the rapid transfer of charge carriers. Additionally, nonequivalent [CuO4]6− layers reduce crystal symmetry, confer PCBO unique piezoelectricity, and improve electron–hole separation under ultrasonic (US) excitation. This allows PCBO to convert US energy into chemical energy to produce ROS, achieving the accumulation of abundant ROS, resulting in apoptosis and tumor suppression. Concurrently, PCBO also acts as a glutathione scavenger to reduce tumor antioxidant capacity and improve efficacy. To the best of authors understanding, this study reveals PCBO as an innovative piezoelectric sonosensitizer and provides a meaningful paradigm for designing energy conversion strategies for tumor suppression.

中文翻译：

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新型空间不对称铋酸铜介导的能量转换增强，实现“三步”肿瘤抑制

无机声敏剂通常不理想的带隙和电子空穴络合限制了活性氧（ROS）的产生效率，影响声动力疗法（SDT）的有效性。相比之下，新型聚乙烯吡咯烷酮改性铋酸铜（PCBO）声敏剂是为了“三步”推广SDT而制造的。简而言之，首先，PCBO中Bi 6s 和O 2p 轨道之间的强杂化缩小了带隙（1.83 eV），有利于载流子的快速转移。此外，非等价的[CuO4]6−层降低了晶体对称性，赋予 PCBO 独特的压电性，并改善超声波 (US) 激励下的电子-空穴分离。这使得PCBO能够将US能量转化为化学能产生ROS，实现丰富ROS的积累，从而导致细胞凋亡和肿瘤抑制。同时，PCBO还作为谷胱甘肽清除剂，降低肿瘤抗氧化能力，提高疗效。据作者所知，这项研究揭示了 PCBO 作为一种创新的压电声敏剂，并为设计用于抑制肿瘤的能量转换策略提供了有意义的范例。