It's tough to deliver medication quickly
and precisely to different parts of the eye.
Traditionally medicine for conditions like glaucoma
or diabetic macular odema is injected into the eye
or dropped onto the surface and left to diffuse
slowly throughout.
This delivery method isn't always accurate
and means the entire eye receives the drug.
The process can be slow irritating and painful for
the patient.
Researchers wanted to build
tiny delivery vehicles they could drive
to deliver cargo quickly to specific
parts of the eye particularly through
the dense jelly called the vitreous humour.
So they use nano scale 3d printing
to create small spiral-shaped delivery bots.
The bots were nearly 200 times smaller
than the diameter of a human hair.
Their tiny size and a nonstick coating made it
easier for them to pass the tight matrix
of the vitreous humour.
The spiral bots also contained magnetic material which
meant the researchers could drive them
forward backward left or right
with a magnetic field.
The scientists injected a solution containing
around 10,000 of the spiral bots into eyes collected
from pigs and put the eyes in a magnetic field.
They used imaging techniques and dissection
to see if the bots have been able to pass through
the eyeball's jelly all the way to the back
where the light the sensing retina lives.
The bots were able to deliver their cargo to
the right place in much less time than
simple diffusion would allow.
Next the researchers are planning to test the spiral bots
in a living animal's eye.
It will be years before any humans have
tiny spiral robots delivering drugs to
the back of their eyes. But the work is a step forward
in building controllable vehicles to aim medicine at
precise targets in sensitive areas of the body.
