Ultrasound Technology May Provide a New Vaccine Delivery Method

Earlier this week, at Acoustics 2023 Sydney, a doctoral researcher at the University of Oxford’s Institute of Biomedical Engineering, Darcy Dunn–Lawless, discussed his research on a painless, needle-free vaccine delivery method using ultrasound technology.

According to a release, the vaccine delivery mechanism is based on an acoustic property, cavitation, which forms and pops bubbles due to sound waves. The researchers hope to accomplish three primary goals using the mechanical energy produced by the popping of bubbles.

“First, to clear passages through the outer layer of dead skin cells and allow vaccine molecules to pass through. Second, to act as a pump that drives the drug molecules into these passages. Lastly, to open up the membranes surrounding the cells themselves, since some types of vaccine must get inside a cell to function,” said Dunn–Lawless in the press release, referring to the multiple uses of mechanical energy.

Despite the potential Dunn–Lawless and his colleagues demonstrated, they noted that 700 times fewer vaccine molecules were delivered by cavitation than injectable vaccines. However, cavitation still yielded a more robust immune response than injection.

The scientists postulate that this incongruency between molecule delivery and immune response may be attributed to the delivery target. They note that immune-rich skin that ultrasonic delivery targets may be superior to the muscles injectables target.

Dunn–Lawless predicts that the potential side effects can be easily managed.

“In my opinion, the main potential side effect is universal to all physical techniques in medicine: If you apply too much energy to the body, you can damage tissue,” Dunn–Lawless said. “Exposure to excessive cavitation can cause mechanical damage to cells and structures. However, there is good evidence that such damage can be avoided by limiting exposure, so a key part of my research is to try and fully identify where this safety threshold lies for vaccine delivery.”

In general, Dunn–Lawless maintains that this delivery method could offer a more effective, safe, and affordable vaccine administration strategy.

The potential benefits of this method need to be evaluated further. Dunn–Lawless continues to work on this research, collaborating with other scientists in Oxford’s Biomedical Ultrasonics, Biotherapy, and Biopharmaceuticals Laboratory (BUBBL).