Recent Developments of Inorganic Nanosensitizers for Sonodynamic Therapy

Abstract

As a noninvasive treatment, sonodynamic therapy (SDT) has been widely used in the treatment of tumors because of its ability to penetrate deep tissue with few side effects. As the key factor of SDT, it is meaningful to design and synthesize efficient sonosensitizers. Compared with organic sonosensitizers, inorganic sonosensitizers can be easily excited by ultrasound. In addition, inorganic sonosensitizers with stable properties, good dispersion, and long blood circulation time, have great development potential in SDT. This review summarizes possible mechanisms of SDT (sonoexcitation and ultrasonic cavitation) in detail. Based on these mechanisms, the design and synthesis of inorganic nanosonosensitizers can be divided into three categories: traditional inorganic semiconductor sonosensitizers, enhanced inorganic semiconductor sonosensitizers, and cavitation‐enhanced sonosensitizers. Subsequently, the current efficient construction methods of sonosensitizers are summarized including accelerated semiconductor charge separation and enhanced production of reactive oxygen species through ultrasonic cavitation. Furthermore, the advantages and disadvantages of different inorganic sonosensitizers and detailed strategies are systematically discussed on how to enhance SDT. Hopefully, this review could provide new insights into the design and synthesis of efficient inorganic nano‐sonosensitizers for SDT.

Improvement of the effectiveness of sonodynamic therapy: by optimizing components and combination with other treatments

“…In many previous studies, inorganic sonosensitizers have been found to have superior physical and chemical properties and high stability and can provide more nucleation sites for cavitation bubbles by ultrasonic stimulation, resulting in continuous ROS generation. 86 Unfortunately, it is obvious that inorganic sonosensitizers need to focus more attention on potential biosafety. [87][88][89][90] The combination of sonosensitizers and nanoplatforms can move beyond some of the inherent drawbacks of sonosensitizers and achieve higher tumor inhibition rates and improved ROS conversion rates.…”

An Ultrasound-Activated Nanozyme Sonosensitizer for Photoacoustic Imaging-Guided Breast Cancer Sonodynamic and Starvation Combination Therapy

“…16,17 Compared with organic sonosensitizers, inorganic sonosensitizers excel in enhancing the therapeutic effect of SDT due to their unique physical properties, such as stability and operability. 18,19 Moreover, some inorganic sonosensitizers not only convert O 2 to 1 O 2 but also break down water to produce hydroxyl radicals (• OH). 20−22 For example, gold-based nanoparticles have been reported to exhibit sonodynamic effects by the cavitation effect.…”

Recent advances in sonodynamic therapy strategies for pancreatic cancer

“…It primarily utilizes the reactive oxygen species (ROS) generated by sonosensitizers when they are exposed to ultrasound (US) waves to selectively destroy cancer cells (Yan et al, 2020; Yang et al, 2019). Therefore, the development of the novel sonosensitizers is important to enhance SDT's efficacy (He et al, 2023). Currently, there are two main categories of developed photosensitizers: organic photosensitizers, like porphyrins, and inorganic photosensitizers, such as titanium dioxide.…”

“…In addition, the ability of US to penetrate deep tissues makes SDT a potential option for treating deep‐seated tumors with minimally invasive surgery (Canaparo et al, 2022; X. Wang et al, 2022; Zeng et al, 2020). As a result, SDT compensates for the penetration depth limitations encountered by other treatment methods, making it a promising approach for targeting tumors located in hard‐to‐reach areas; thus, it is particularly valuable for managing pancreatic cancer (He et al, 2023). Third, with the help of US, the efficiency of ROS generation is much higher than the therapy strategy based on catalytic medicine (Guan et al, 2022; Lu et al, 2020; Shi et al, 2021; Teng et al, 2021; Yang et al, 2022; Yue et al, 2022).…”