Sounding the death knell for microbes?

• Sonodynamic antimicrobial chemotherapy (SACT) kills microbes by the ultrasound activation of phototoxic sonosensitizers.
• SACT has the potential as a form of ultrasound-mediated antimicrobial therapy.

Over the past 5 years, several studies showed that ultrasound, which is sound with a frequency >20 kHz, is able to kill bacteria by activating molecules termed sonosensitizers (SS) to produce reactive oxygen species, which are toxic to microbes. It is our opinion that this work opens up the potential for the development of a novel form of ultrasound-mediated antimicrobial therapy. Termed sonodynamic antimicrobial chemotherapy (SACT), we define this therapy as a regime where a SS is selectively delivered to target microbial cells and activated by ultrasound to induce the death of those microbial cells. Here, we review recent work on SACT, current understanding of its mechanisms, and future prospects for SACT as a therapeutically viable antimicrobial regime.