Critters on a Chip
(or what is the HBM for bacteria?)
By: Elizabeth Nelson
exciting developments are taking place at the former top-secret
nuclear plant in Oak Ridge, TN. One of the most innovative is
'Critters on a Chip.'
Mike Simpson has developed an amazing
part-living, part-silicon chip that can detect pollutants, explosives,
and various chemicals in water and soil. Critters on a Chip (2
millimeters x 2 millimeters) consists of living sensors (including
bioluminescent bacteria) placed on a standard integrated circuit.
We wonder if Dr. Simpson has ran ESD characterization tests on
When pollutants, explosives, or other
targeted substances get close to the chip, the bioluminescent
bacteria emits a blue-green light. The chip may also be used to
transmits signals to computers which is helpful in medial disgnostics
and industrial process monitors. Simpson explains "Because
the integrated circuits are small, low-power, rugged and can be
made wireless, they can be placed in areas other devices cannot."
Many times biological signals are
extremely faint. Sometimes, medical professionals have trouble
reading a person's blood type, and other vital signs. Current
tests to determine Rh factors in blood, presence of HIV, and chemical
signatures of heart attacks can be life-threateningly slow. Because
of this need, scientists have been trying to develop a microcircuit
that is able to better detect these molecules since the 1970's.
However, it is very difficult to mix microchips and liquids. When
a mix is created, it is usually too expensive or not flexible
enough to use bor drugs and viruses.
The critters on a chip could replace
today's bulky, expensive and complicated optical detection systems
that use photo multipliers and optical fibers buried in the ground.
It could also allow for more extensive monitoring of a remediation
site with no increase in cost.
The sensor that has been unveiled
by Oak Ridge National Laboratory inventors uses a genetically
engineered bacterium known as Pseudomonas fluorescens HK 44. This
solution is extremely sensitive to the common petroleum pollutant
This is useful for monitoring hazardous waste sites.
The product is expected to be reasonably
priced under $1 and disposable. Unfortunately, there is a downside
to Critters on a Chip. The bacteria that live on the circuit need
food and it is possible for the bacteria to die and/or mutate.
This will inevitably lead to experation dates on the chips.
It is still unknown when Critters
on a Chip can be expected on the market.