Department of Applied Science and Technology, Politecnico Di Torino, C.So Duca Degli Abruzzi 24, 10129, Turin, Italy.
CESAM - Universidade de Aveiro, Campus Universitário de Santiago, Aveiro, Portugal.
Biomed Microdevices. 2024 Aug 19;26(3):37. doi: 10.1007/s10544-024-00720-3.
Ultrasound radiation has been widely used in biomedical application for both diagnosis and therapy. Metal oxides nanoparticles (NPs), like ZnO or TiO NPs, have been widely demonstrated to act as excellent sonocatalysts and significantly enhance cavitation at their surface, making them optimal for sonodynamic cancer therapy. These NPs often possess semiconductive and piezoelectric properties that contribute to the complex phenomena occurring at the water-oxide interface during sonostimulation. Despite the great potential in applied sonocatalysis and water splitting, the complex mechanism that governs the phenomenon is still a research subject. This work investigates the role of piezoelectric ZnO micro- and nano-particles in ultrasound-assisted water oxidation. Three metal oxides presenting fundamental electronic and mechanical differences are evaluated in terms of ultrasound-triggered reactive oxygen species generation in aqueous media: electromechanically inert SiO NPs, semiconducting TiO NPs, piezoelectric and semiconducting ZnO micro- and nanoparticles with different surface areas and sizes. The presence of silver ions in the aqueous solution was further considered to impart a potential electron scavenging effects and better evaluate the oxygen generation performances of the different structures. Following sonoirradiation, the particles are optically and chemically analyzed to study the effect of sonostimulation at their surface. The production of gaseous molecular oxygen is measured, revealing the potential of piezoelectric particles to generate oxygen under hypoxic conditions typical of some cancer environments. Finally, the best candidates, i.e. ZnO nano and micro particles, were tested on osteosarcoma and glioblastoma cell lines to demonstrate their potential for cancer treatment.
超声辐射已广泛应用于生物医学诊断和治疗领域。金属氧化物纳米粒子（NPs），如 ZnO 或 TiO2 NPs，已被广泛证明是出色的声催化剂，并能显著增强其表面的空化作用，使其成为声动力学癌症治疗的理想选择。这些 NPs 通常具有半导体和压电特性，有助于解释在声刺激过程中发生在水-氧化物界面的复杂现象。尽管在应用声催化和水分解方面具有巨大潜力，但控制这一现象的复杂机制仍然是一个研究课题。本工作研究了压电 ZnO 微纳粒子在超声辅助水氧化中的作用。评估了三种具有基本电子和机械差异的金属氧化物，以评估它们在水介质中超声触发的活性氧物种生成的能力：电机械惰性的 SiO2 NPs、半导体 TiO2 NPs、具有不同表面积和尺寸的压电和半导体 ZnO 微纳粒子。还进一步考虑了在水溶液中存在银离子，以赋予潜在的电子捕获效应，并更好地评估不同结构的氧气生成性能。在超声照射后，通过光学和化学分析研究了表面声刺激的影响。测量了气态分子氧的产生，揭示了压电粒子在一些典型的癌症缺氧环境下产生氧气的潜力。最后，测试了最佳候选物 ZnO 纳米和微粒子对骨肉瘤和神经胶质瘤细胞系的作用，以证明它们在癌症治疗中的潜在应用。
