Forget Shots - New Implants Could Deliver Meds
If you’re diabetic or have Pernicious anemia you have to
manage injections, sometimes daily. Now there’s hope for treating such
chronic diseases via implants powered by nothing more than
light-triggered engineered cells.
The implants could also monitor toxins in the body in real time,
providing long-term health data — either warning you to take your heart
meds or even administering the meds themselves.
The technology, reported in the journal Nature Photonics,
consists of transparent polymer implants. Each implant has genetically
modified cells in it that activate in response to light. The cells can
be programmed to release chemicals.
Myunghwan Choi and Seok Yun led a joint Harvard University and
University of Toronto team to build a set of implants made of hydrogel, a
polymer material that is compatible with tissue. Each hydrogel implant
was 4 millimeters by 40 millimeters, and only a millimeter thick. The
patches were loaded up with cells engineered to respond to light.
Choi and Yun demonstrated the implants in two ways. In one
experiment they used them to deliver insulin, and in another they were
toxin detectors.
The insulin system was used on diabetic mice. The scientists
sent blue light through an optical fiber to the implant, inducing the
cells in the implant to make a protein that stimulates insulin
production.
For the toxin detection, the engineered cells emitted green
light in the presence of heavy metals. By measuring the light levels
from the implant, they could see how much heavy metal was present.
There is still work to be done before it gets to local clinics.
First, the cells have to be taken from the host — otherwise there is
the risk of immune reactions. Also, the transmission of light through
the hydrogel has to be extended — humans are bigger than mice. Third, it
will take time to discover how porous the hydrogels should be in order
to best deliver the kinds of drugs necessary.
If that happens, one day our bodies could be networked as much as our devices.