A study from MIT’s Mechanical Engineering Department suggests ultrasounds have the potential to damage coronaviruses.
Simulations show ultrasound waves at medical imaging frequencies can cause the virus’ shell and spikes to collapse and rupture.Through computer simulations, the team modeled the virus’ mechanical response to vibrations across a range of ultrasound frequencies. They found that vibrations between 25 and 100 megahertz triggered the virus’ shell and spikes to collapse and start to rupture within a fraction of a millisecond. This effect was seen in simulations of the virus in air and in water.
The team started with vibrations of 100 megahertz, or 100 million cycles per second, which they estimated would be the shell’s natural vibrating frequency, based on what’s known of the virus’ physical properties.
When they exposed the virus to 100 MHz ultrasound excitations, the virus’ natural vibrations were initially undetectable. But within a fraction of a millisecond the external vibrations, resonating with the frequency of the virus’ natural oscillations, caused the shell and spikes to buckle inward, similar to a ball that dimples as it bounces off the ground.
As the researchers increased the amplitude, or intensity, of the vibrations, the shell could fracture — an acoustic phenomenon known as resonance that also explains how opera singers can crack a wineglass if they sing at just the right pitch and volume. At lower frequencies of 25 MHz and 50 MHz, the virus buckled and fractured even faster, both in simulated environments of air, and of water that is similar in density to fluids in the body.
To refine and validate their simulations, the team is working with microbiologists in Spain, who are using atomic force microscopy to observe the effects of ultrasound vibrations on a type of coronavirus found exclusively in pigs. If ultrasound can be experimentally proven to damage coronaviruses, including SARS-CoV-2, and if this damage can be shown to have a therapeutic effect, the team envisions that ultrasound, which is already used to break up kidney stones and to release drugs via liposomes, might be harnessed to treat and possibly prevent coronavirus infection. The researchers also envision that miniature ultrasound transducers, fitted into phones and other portable devices, might be capable of shielding people from the virus.
The potential of ultrasound machines is endless.