A Form-fitting Photovoltaic Artificial Retina

Retina chip gets both power and data from near-infrared light

4 min read

22 December 2009—Several teams of scientists and engineers have been trying for years to produce a practical retinal prosthesis for people afflicted by a progressive loss of photoreceptor cells. One problem all the researchers face is how to get power and data (the image) to a retinal chip that’s implanted at the back of a person’s eye. Some groups’ implants, such as those from the University of Southern California’s Doheny Eye Institute and an MIT-Harvard team get their power and data from RF signals beamed in from the outside, while other groups, including one at the University Eye Hospital in Tübingen, Germany, are working on getting the data as light entering the eye using RF energy to beam in the power. But a team from Stanford University has been working on what might seem like the obvious solution: using light entering the eye for both power and data.

The Stanford implant is designed as an array of miniature solar cells. The device—technically a subretinal implant, because it is placed behind the retina—is part of a system that includes a video camera that captures images, a pocket PC that processes the video feed, and a bright near-infrared LCD display built into video goggles. The pulsed 900-nanometer-wavelength image that shines into the eyes is enough to produce electricity in the chip. (A chip driven by just the ambient light coming in to your eye would produce current that is one-thousandth or less the strength required to trigger retinal neurons.) The researchers chose a near-infrared display because it is invisible. Some patients’ retinas might still have some working photoreceptors that could be stimulated by visible light. Visible light bright enough to stimulate cells would yield artifacts that would muddy the image generated in the brain.

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This CAD Program Can Design New Organisms

Genetic engineers have a powerful new tool to write and edit DNA code

11 min read
A photo showing machinery in a lab

Foundries such as the Edinburgh Genome Foundry assemble fragments of synthetic DNA and send them to labs for testing in cells.

Edinburgh Genome Foundry, University of Edinburgh

In the next decade, medical science may finally advance cures for some of the most complex diseases that plague humanity. Many diseases are caused by mutations in the human genome, which can either be inherited from our parents (such as in cystic fibrosis), or acquired during life, such as most types of cancer. For some of these conditions, medical researchers have identified the exact mutations that lead to disease; but in many more, they're still seeking answers. And without understanding the cause of a problem, it's pretty tough to find a cure.

We believe that a key enabling technology in this quest is a computer-aided design (CAD) program for genome editing, which our organization is launching this week at the Genome Project-write (GP-write) conference.

With this CAD program, medical researchers will be able to quickly design hundreds of different genomes with any combination of mutations and send the genetic code to a company that manufactures strings of DNA. Those fragments of synthesized DNA can then be sent to a foundry for assembly, and finally to a lab where the designed genomes can be tested in cells. Based on how the cells grow, researchers can use the CAD program to iterate with a new batch of redesigned genomes, sharing data for collaborative efforts. Enabling fast redesign of thousands of variants can only be achieved through automation; at that scale, researchers just might identify the combinations of mutations that are causing genetic diseases. This is the first critical R&D step toward finding cures.

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