Microbubble technology bypasses blood brain barrier, says researcher

11-Sep-2018 - Last updated on 08-Aug-2019 at 18:08 GMT

(Image: Getty/Verger)

A study at Washington University in St. Louis has shown a new way to deliver drugs to the brainstem in a non-invasive administration: microbubbles and ultrasound.

Hong Chen, assistant professor at Washington University, conducted a study of a drug delivery system that gets medications to the brainstem. The study is to be published next month in the journal Controlled Release.

Chen’s drug delivery system is called FUSIN, or focused ultrasound with intranasal delivery.

“The fundamental hypothesis of this study was that blood vessel expansion and contraction induced by microbubble expansion and contraction can enhance the transport of intranasally-administered agents into the focused ultrasound-targeted brain region,” said Chen.

The microbubbles work as a contrast agent in the ultrasound. When ultrasound waves are focused on them, the bubbles expand and contract to pump directly towards the brainstem – similarly to red blood cells.

“Microbubbles are unique in that they expand and contract when sonicated by ultrasound, which pushes and pulls on the vessel wall and potentially contributes to the enhanced and localized brain drug delivery observed in this study,” Chen further explained.

FUSIN works on two nerves, olfactory and trigeminal, to carry the nanoparticles directly to the brain.

By bypassing the blood-brain barrier, the drug can reach the brain stem, which previously has been a challenge, and once doing so it can target the drug delivery to the tumor itself.

According to the study, not only does this delivery technology allow for the drug to target a specific area, it also prevents toxicity as the drug does not circulate around the body.

Pushing the bubbles forward

FUSIN, according to Chen, may be the answer to treating brain-based diseases. In particular, it is believed by researchers that this system would be especially powerful in curing diffuse intrinsic pontine gliomas (DIPG), a pediatric brain cancer with a five-year survival rate of 2%.

However, Chen believes that this technique is not limited solely to DIPG, but can be applicable for the use of treating other brain cancers and Alzheimer’s disease.