Ultrasound drug delivery is an emerging technology for more precisely targeted medication without the side effects.
By Saminder Marwa
Side effects might soon be history, thanks to nanoparticles and sound.
The problem with side effects
Ever noticed the folded leaflet inside medicine boxes, speedily-read warnings at the end of a drug advert, or been reminded to check the label of medication you take before driving? They all have one thing in common—side effects.
We know that medicines work wonders: Painkillers stop pain receptors from even detecting pain, anesthetic allows surgery to be more precise, antibiotics stop a simple cut from being a death sentence. However, some medicines target the wrong area, leading to side effects, like the common chemotherapy side effect of hair loss, and nausea after taking antibiotics.
Side effects are defined as any “unintended,” secondary effect. The phrase is used, in terms of medication, to describe other impacts that medicine can have. And this doesn’t just apply to feeling sleepy after taking medicine—side effects can be much more serious. The common cancer treatment, chemotherapy, has a side effect of damaging healthy cells, leading to hair loss, and weakening the immune system, making patients more susceptible to infections.
Nanotech for drug delivery
So if we know that medicines have a hard time finding where to go, how can we make them more precise? A new study from Stanford Medicine answers exactly that by presenting an innovative solution to deliver drugs with extreme precision, within a few millimeters of the target area. This technology uses a super-small package, a nanoparticle, to wrap around drugs and prevent them being released until needed, at their target destination. These ultra-tiny packaging containers are about 1/100,000 width of a strand of a human hair. They shield the drug as it travels through the body, preventing unwanted effects outside the target area.
Nanoparticles aren’t new to scientists. This idea of wrapping drugs has many challenges; earlier nanoparticles were made of uncommon compounds, making them expensive and complex to make. They also had to be stored at sub-zero temperatures, specifically -80 degrees Celsius (-112 degrees Fahrenheit) and weren’t stable at body temperature.
These issues made it nearly impossible to use nanoparticles effectively in human treatments, as the medicine would degrade before reaching its target. To solve this, researchers used a phospholipid shell, made of the same material found in cell membranes. These shells were also used in the COVID-19 mRNA vaccines. This meant that the technology to manufacture them was widely available, affordable, and fast enough to keep up with demands.
Nanotech and ultrasound drug delivery: a smarter way to heal
Scientists had a breakthrough when they realized ultrasound waves could be used to break open this shell at the right place. Ultrasound is a type of sound that has such a high frequency that humans cannot hear it. It might be familiar from its use in prenatal pregnancy scans to visualize the fetus.
To make these nanoparticles distinguishable and differentiated by ultrasound, these nanoparticles need to be either more or less easy for sound waves to move through the material, and so, less dense.
To make these nanoparticles more responsive to ultrasound, the scientists added a solution of 5 percent sucrose sugar to the liquid core of these liposomes. This solved the balance of ensuring these liposomes would be detected by ultrasound, as well as maintaining the stability. The nanoparticle shells are machined to be ultrasound-sensitive, so if we make sure that we release ultrasound waves at the target area, we can make sure the drugs only reach where they’re needed.
Trialing the ultrasound method
When tested against an injection of free-floating ketamine in mice, researchers found that mice that they had treated with the novel ultrasound drug delivery had less than 50 percent of ketamine in each organ. Furthermore, the mice had three times the amount of ketamine in the target area than other parts of the same organ with liposomes compared to the control. The usage of liposomes meant a controlled, targeted ultrasound drug delivery that led to a reduction in anxious behavior. This change in delivery method could make ketamine a prospective treatment for depression, without the side effects of dissociation.
The researchers also explored using ultrasound drug delivery to a specific muscle group or nerve, which proved to be effective in mice. This would be a huge advantage to patients in pain, as local anesthetics wouldn’t have to be injected at the site of the pain, but could instead be injected anywhere else.
Learn more about ultrasound innovations in Neuromodulation: How We Manipulate Brain Cells
Why it matters: the future of precision medicine
While the results in mice are promising, researchers must now conduct further testing to ensure the technology works in humans, particularly in how the nanoparticles respond within different tissues and organs. As of now, early trials are in planning to trial ketamine targeting in humans using this technology to tackle chronic pain.
In sum, this new technology utilizes ultrasound drug delivery to make medicine smarter, safer, and more efficient. The implications for the future of healthcare are huge—from treatments for Parkinson’s and Alzheimer’s, to reduced side effects of chemotherapy, and making pain management more effective. This technology has the ability to act as a GPS system for medicine, paving the way for chemotherapy with fewer side effects and faster recovery times.
This study was published in the peer-reviewed journal Nature Nanotechnology.
Reference
Purohit, M. P., Yu, B. J., Roy, K. S., et al. (2025). Acoustically activatable liposomes as a translational nanotechnology for site-targeted drug delivery and noninvasive neuromodulation. Nature Nanotechnology, 20, 1688–1699. https://doi.org/10.1038/s41565-025-01990-5
Featured image of a nanoparticle chemistry lab by Rede Galega de Biomateriais on Flickr, licensed as CC BY-NC 2.0.
About the Author
Saminder Marwa is a Biology BSc student studying at Queen Mary, University of London. She is fascinated by how science can reshape healthcare—from drug development and designing smarter, safer medicines, to cancer research. Her work explores how innovation in biology and technology can make medicine more precise, effective, and kind to the body. Connect with her on LinkedIn.
