Thanks to a new nasal spray which uses gold nanoparticles to cross through the blood-brain barrier, life-saving medicines could soon be sent directly to the brain with just a sniff.
This protective barrier is keeping our brains safe from damaging toxins, but also makes it hard for beneficial drugs to be effective. So this nasal mode of delivery could enable all kinds of new treatments.
This spray has been developed by a team from Washington University in St. Louis. The team tested it on the antennae of locusts – insects with blood-brain barriers and olfactory networks that are anatomically similar to those in humans.
According to researchers, the nasal spray method could deliver drugs to the brain in as little as 30 to 60 minutes, based on these tests.
“The shortest and possibly the easiest path to the brain is through your nose,” says one member of the team, Barani Raman.
“Your nose, the olfactory bulb and then olfactory cortex: two relays and you’ve reached the cortex.”
The researchers have developed an aerosol spray made up of gold nanoparticles small enough to pass through the blood-brain barrier. In order to track the movement of the nanoparticles, fluorescent markers were added.
The nanoparticles moved through the antennas, olfactory nerves, and blood-brain barrier in just a few minutes, after exposing locusts to the spray, before spreading through the brain.
There are no noticeable changes noticed in the olfactory neurons of the locusts after the treatment, suggesting minimal disruption to brain function.
Adapting the technique are the next stages, so the gold nanoparticles can carry different types of medicines – and of course to see if the same approach could work with humans in addition to locusts.
If it does, this could be the best option yet for drug delivery to the brain. Pills aren’t precise at all and the medications contained in them struggle to get through the blood-brain barrier, while injections into the brain are invasive and risk damaging tissue.
This nasal spray is the latest example showing how nanotechnology could help improve our health: whether it’s fighting cancer or stopping allergies, we’re seeing tiny nanoparticles show a lot of potential for treating areas of the body that other drugs struggle to reach.
However, nanoparticles can be very carefully targeted thanks to their microscopic size – as in the case of chemotherapy drugs designed to hit cancer without affecting healthy tissue.
The scientists suggest their work could lead to more improved treatments for several health problems, including brain tumours, which could be targeted using a combination of a nasal spray and ultrasound.
Raman says: “This is only a beginning of a cool set of studies that can be performed to make nanoparticle-based drug delivery approaches more principled.“