Rat Nerve Cell Pings Computer Chip
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Rat Nerve Cell Pings Computer Chip
By Tracy Staedter, Discovery News
April 19, 2006- A rat nerve cell attached to a semiconductor chip has
exchanged a signal with the chip, an achievement that could lead to
organic computers that process information like a brain, say
researchers.
In the long term, the technology also could lead to prosthetic limbs
that are controlled by a person's brain and nerves.
"If you know how single neurons couple to a chip, you can learn how
whole tissue couples to a chip," said Peter Fromherz, professor of
biophysics at Max Planck Institute for Biochemistry in Germany and
coordinator of the so-called NaChip project, which also involves
researchers from the University of Padua, Italy, and the University of
Zurich, Switzerland.
To make the nerve cell and the chip compatible, the researchers worked
with German microchip company Infineon to modify the chip's surface.
The resulting one-millimeter chip has more than 16,000 transistors that
match up with ion-carrying channels in the nerve cell.
The chips were specially coated so that they could be immersed in a
solution meant to keep the nerve cell alive.
Next, the team zeroed in on the protein fibronectin, which is involved
in many cellular processes, including tissue repair, blood clotting,
and cell adhesion. The scientists grew the nerve cell on the protein
and then used the protein to adhere the nerve to the silicon chip.
In addition to helping the cell adhere, the protein also served as a
gate through which charged particles of sodium - the "Na" in NaChip
- could move between the nerve and transistor.
By measuring the charge on the chip, the scientists confirmed that the
electrical pulses from the active neuron were finding their way to it.
They were also able to stimulate the nerve cell by sending an
electrical pulse from the chip's capacitors.
"From a major technology breakthrough point of view, the technique will
revolutionize the way it's done," said professor Naweed Syed, head of
the department of cell biology and anatomy at the University of
Calgary.
Eventually, the NaChip team plans to move beyond the single rat cell to
rat brain. According to Fromherz, the scientists have all of the tools
to couple hundreds of neurons to a semiconductor chip and conceivably
perform simple computations.