Courtesy of Stanford University Medical Center
Using live cells arrayed on a chip, a Stanford University team has prototyped an implantable silicon wafer designed not only to improve sight in macular degeneration patients, but also to dispense drugs and collect fluid samples inside the body.1 The implant, now in development, will be nearly 2.5 cm in diameter, 10 microns thick, and honeycombed with hundreds of microchannels, which will dispense neurotransmitters either from onboard stores or a tiny reservoir implanted nearby.
Implanted in the macula, the part of the retina directly behind the pupil, the chip will be photoactivated: Light striking the chip creates an electric field that moves the transmitters (which will replace those the dead or dormant macular cells cannot provide) through the channels and out tiny apertures. The light's intensity will control dosage.
The same chip could both dispense drugs in the brain or elsewhere in the...