Studeo
10th June 2010, 17:15
Part-Human, Part-Machine Transistor Devised
http://news.discovery.com/tech/transistor-cell-membrane-machine.html
By embedding a nano-sized transistor inside a cell-like membrane,
scientists link humans and machines more intimately than ever.
By Eric Bland
Wed Jun 2, 2010 10:46 AM ET
Man and machine can now be linked more intimately than ever, according
to a new article in the journal ACS Nano Letters. Scientists have
embedded a nano-sized transistor inside a cell-like membrane and
powered it using the cell's own fuel.
The research could lead to new types of man-machine interactions where
embedded devices could relay information about the inner workings of
disease-related proteins inside the cell membrane, and eventually lead
to new ways to read, and even influence, brain or nerve cells.
"This device is as close to the seamless marriage of biological and
electronic structures as anything else that people did before," said
Aleksandr Noy, a scientist at the University of California, Merced who
is a co-author on the recent ACS Nano Letters. "We can take proteins,
real biological machines, and make them part of a working
microelectronic circuit."
To create the implanted circuit, the UC scientists began with a simple
transistor, an electronic device that is the heart of nearly every
cell phone and computer on the planet. Instead of using silicon, the
most common material used in transistors, the scientists used a next
generation material known as a carbon nanotube, a tiny straw-shaped
material made from a single curved layer of carbon atoms arranged like
the panels of a soccer ball.
The scientists then coated the carbon nanotube transistor with a lipid
bilayer, basically a double wall of oil molecules that cells use to
separate their insides from their environment. The scientists didn't
use an actual cell membrane, however.
To this basic cellular structure the UC scientists added an ion pump,
a biological device that pumps charged atoms of calcium, potassium,
and other elements into and out of the cell. Then they added a
solution of adenosine tri-phosphate, or ATP, which fuels the ion pump.
The ion pump changes the electrical charge inside the cell, which then
changes the electrical charge going through the transistor, which the
scientists could measure and monitor.
In their initial device the biological pump powered the artificial
transistor. Future devices could work just the opposite, where an
outside electrical current could power the pump and alter how quickly
ions are pumped into or out of a cell. That could have dramatic
effects.
For instance, instead of using drugs to block the release or uptake of
various drugs or neurotransmitters, scientists could change the
electricity regulating the ion pump, which would then change the
amount of the drug or molecule inside, or outside, the cell.
Other groups have tried to mix man and machine before, said Itamar
Willner, a scientist from the Hebrew University of Jerusalem, but none
have achieved this level of intimacy.
"Previous students used enzymes that were not incorporated into
membranes in the transistors," said Willner. "In this case, an enzyme
that usually works in the membrane was linked to carbon nanotubes."
The new enzyme-transistor link could help eventually monitor and even
treat diseases and conditions, said Willner.
Some of the most obvious medical conditions the embedded transistor
could help study, or alleviate, are toxins and poisons. Many of these
chemicals puncture cell membranes and cause the cell's inner fluid, or
cytoplasm, to leak out, essentially bleeding the cell to death. Other
toxins create ion imbalances inside the cells, which can cause
paralysis and other conditions.
If the cells could be encouraged to pump the necessary ions into or
out of the cell that could help treat a specific condition. Though any
actual treatment based on this technology is still years away, said
Willner.
"We don't want to just sense things, we also want to treat them," said
Willner. Clinical applications may still be years away, but the new
research is the most intimate link between life and machines that has
yet been created.
http://news.discovery.com/tech/transistor-cell-membrane-machine.html
By embedding a nano-sized transistor inside a cell-like membrane,
scientists link humans and machines more intimately than ever.
By Eric Bland
Wed Jun 2, 2010 10:46 AM ET
Man and machine can now be linked more intimately than ever, according
to a new article in the journal ACS Nano Letters. Scientists have
embedded a nano-sized transistor inside a cell-like membrane and
powered it using the cell's own fuel.
The research could lead to new types of man-machine interactions where
embedded devices could relay information about the inner workings of
disease-related proteins inside the cell membrane, and eventually lead
to new ways to read, and even influence, brain or nerve cells.
"This device is as close to the seamless marriage of biological and
electronic structures as anything else that people did before," said
Aleksandr Noy, a scientist at the University of California, Merced who
is a co-author on the recent ACS Nano Letters. "We can take proteins,
real biological machines, and make them part of a working
microelectronic circuit."
To create the implanted circuit, the UC scientists began with a simple
transistor, an electronic device that is the heart of nearly every
cell phone and computer on the planet. Instead of using silicon, the
most common material used in transistors, the scientists used a next
generation material known as a carbon nanotube, a tiny straw-shaped
material made from a single curved layer of carbon atoms arranged like
the panels of a soccer ball.
The scientists then coated the carbon nanotube transistor with a lipid
bilayer, basically a double wall of oil molecules that cells use to
separate their insides from their environment. The scientists didn't
use an actual cell membrane, however.
To this basic cellular structure the UC scientists added an ion pump,
a biological device that pumps charged atoms of calcium, potassium,
and other elements into and out of the cell. Then they added a
solution of adenosine tri-phosphate, or ATP, which fuels the ion pump.
The ion pump changes the electrical charge inside the cell, which then
changes the electrical charge going through the transistor, which the
scientists could measure and monitor.
In their initial device the biological pump powered the artificial
transistor. Future devices could work just the opposite, where an
outside electrical current could power the pump and alter how quickly
ions are pumped into or out of a cell. That could have dramatic
effects.
For instance, instead of using drugs to block the release or uptake of
various drugs or neurotransmitters, scientists could change the
electricity regulating the ion pump, which would then change the
amount of the drug or molecule inside, or outside, the cell.
Other groups have tried to mix man and machine before, said Itamar
Willner, a scientist from the Hebrew University of Jerusalem, but none
have achieved this level of intimacy.
"Previous students used enzymes that were not incorporated into
membranes in the transistors," said Willner. "In this case, an enzyme
that usually works in the membrane was linked to carbon nanotubes."
The new enzyme-transistor link could help eventually monitor and even
treat diseases and conditions, said Willner.
Some of the most obvious medical conditions the embedded transistor
could help study, or alleviate, are toxins and poisons. Many of these
chemicals puncture cell membranes and cause the cell's inner fluid, or
cytoplasm, to leak out, essentially bleeding the cell to death. Other
toxins create ion imbalances inside the cells, which can cause
paralysis and other conditions.
If the cells could be encouraged to pump the necessary ions into or
out of the cell that could help treat a specific condition. Though any
actual treatment based on this technology is still years away, said
Willner.
"We don't want to just sense things, we also want to treat them," said
Willner. Clinical applications may still be years away, but the new
research is the most intimate link between life and machines that has
yet been created.