Nanosonotechnology: the next challenge in cancer sonodynamic therapy

Sonodynamic therapy (SDT) is a newly developed anti-cancer treatment where ultrasounds are used to trigger the cytotoxic effect of chemical compounds, known as sonosensitizers. Although SDT is similar to photodynamic therapy (PDT), it differs in as much as the activation of the chemical compounds is achieved by energy transfer through ultrasounds rather than light. Moreover, SDT is able to focus the ultrasound energy onto malignant sites situated deeply within tissues, therefore, overcoming the main drawback linked to the use of PDT. Several physical and chemical mechanisms underlying ultrasound bioeffects and anti-cancer SDT take advantage of the non-thermal effect of acoustic cavitation generated by selected pulsed, or continuous ultrasounds. Since the physical-chemical structure of the sonosentizer is essential for the success of SDT, we believe that the different aspects related to nanotechnology in medicine might well be able to improve the triggering effect ultrasounds have on sonosensitizing agents. herefore, the aim of this review is to focus on how nanotechnology might improve this innovative anticancer therapeutic approach.