Sun Wanying, Yan Xiaoxiao, Li Yingshu, Meng Nianqi, Feng Yufeng, Li Wei, Guo Xiaolu, Shen Xing-Can, Gao Cunji
Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources (Ministry of Education of China), Guangxi Key Laboratory of Chemistry and Molecular Engineering of Medicinal Resources, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, P. R. China.
ACS Nano. 2025 Jul 15;19(27):25422-25437. doi: 10.1021/acsnano.5c07358. Epub 2025 Jul 2.
Although bismuth sulfide (BiS) possesses a narrow bandgap, advantageous for sonodynamic therapy (SDT), a substantial portion of ultrasound (US)-excited electrons is lost due to rapid electron-hole pair recombination, hindering their surface participation in redox reactions. In this study, a sulfur vacancy engineering strategy was implemented to yield BiS with -generated abundant sulfur vacancies, which significantly enhanced electron-hole pair separation for reactive oxygen species (ROS) production under US irradiation. Subsequently, platinum (Pt) nanoparticles were grown on the BiS surface, forming a BiS-Pt Schottky heterojunction and optimizing catalytic activity. These Pt nanoparticles functioned as electron traps, inducing upward energy band bending and establishing a Schottky barrier, thereby bolstering electron-hole pair separation under US stimulation. Furthermore, the catalase (CAT)- and peroxidase (POD)-like activities of the Pt nanoparticles mitigated tumor hypoxia to augment SDT-induced singlet oxygen generation and triggered oxidative stress, respectively. Sono-excited holes were capable of depleting excessive intratumoral glutathione (GSH) and decomposing hydrogen peroxide into O, thus alleviating tumor hypoxia and consequently remodeling the tumor microenvironment. To further enhance tumor targeting and dispersity, BiS-Pt was modified with hyaluronic acid (HA), which specifically binds to CD44 receptors overexpressed on tumor cells. BiS-Pt@HA, exhibiting these combined functionalities, significantly suppressed tumor proliferation. This study outlines a methodology for enhancing the ROS generation efficiency of inorganic sonosensitizers characterized by narrow bandgaps.
尽管硫化铋（BiS）具有窄带隙，有利于声动力疗法（SDT），但由于电子-空穴对的快速复合，超声（US）激发的电子有很大一部分会损失，这阻碍了它们在表面参与氧化还原反应。在本研究中，实施了一种硫空位工程策略，以制备具有大量硫空位的BiS，这显著增强了在US照射下产生活性氧（ROS）时的电子-空穴对分离。随后，在BiS表面生长铂（Pt）纳米颗粒，形成BiS-Pt肖特基异质结并优化催化活性。这些Pt纳米颗粒起到电子陷阱的作用，引起能带向上弯曲并建立肖特基势垒，从而在US刺激下增强电子-空穴对的分离。此外，Pt纳米颗粒的过氧化氢酶（CAT）样和过氧化物酶（POD）样活性分别减轻了肿瘤缺氧，以增加SDT诱导的单线态氧生成并引发氧化应激。声激发的空穴能够消耗肿瘤内过量的谷胱甘肽（GSH）并将过氧化氢分解为O，从而减轻肿瘤缺氧并因此重塑肿瘤微环境。为了进一步增强肿瘤靶向性和分散性，用透明质酸（HA）修饰BiS-Pt，HA能特异性结合在肿瘤细胞上过度表达的CD44受体。具有这些综合功能的BiS-Pt@HA显著抑制了肿瘤增殖。本研究概述了一种提高具有窄带隙的无机声敏剂ROS生成效率的方法。
