Bio/Chem agent detection and decontamination

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Bio/Chem agent detection and decontamination
Kin P. Cheung
Electrical Computer Engineering
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The most dangerous bioagent attack is in the form
of aerosol
An adult human inhales 10 100 liter per minute
of air
Infective doses of selected aerosol BW
agents Anthrax 800010,000 spores 5
spores/Liter Brucellosis 10100
organisms 0.01 /Liter Plague 3000
organisms 1 /Liter Q fever 110
organisms 0.001 /Liter Tularemia 1050
organisms 0.01 /Liter Smallpox 10100
organisms 0.01 /Liter Viral encephalitides
10100 organisms 0.01 /Liter Viral hemorrhagic
fevers 110 organisms 0.001 /Liter Botulinum
toxin 0.07 µg/kg 3ng /Liter Staph.
enterotoxin B 0.02 ug/kg (lethal) 1ng /Liter
D. R. Walt, D. R. Franz, Analytical Chem. 72(23),
738A(2000).
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Assume a particle 104 heavier than air molecule
Average thermal velocity 400cm/s
The impingement rate to a 1cm2 area detecting
surface is
Passive detector is out of the question.
Sample concentration method that collect 1000
liters of air in one minute is needed.
Ultra compact detector is not a practical goal.
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Large number of detectors are assumed to be in a
distributed network that requires minimum human
intervention for extended period.
For civilian protection, sufficient time must be
budgeted for after alarm procedure
Detector that requires consumable is not
practical.
Immunoassay based technology is not attractive.
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Optical detection has fundamental issues
The basic composition of all life form are the
same.
Very little difference between microbes
How to tell the difference between naturally
occurring and harmless aerosols from harmful one?
High false alarm rate is worse than no alarm.
The only region of spectrum that has the
potential to distinguish one microbe from another
is the millimeter wave.
High-resolution THz spectroscopy is very
promising.
A unique, ultra high sensitivity, ultra broad
band, ultra high resolution THz spectroscopy
method is being developed for bio-aerosol
detection here at Rutgers.
The three ultras are of key important!
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Bio/Chem agent decontamination using non-thermal,
atmospheric pressure plasma
Atmospheric pressure, non-thermal plasma is well
known to have high potential for waste gas
treatment and medical instrument sterilization.
The main problem has been cost.
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The promising potential of plasmas for decon was
clearly identified during the U.S. Militarys
Decon Front End Analysis (FEA) conducted in
December 1998. This FEA forms the backbone of the
Joint Services Decon Master Plan. Technologies
were graded against 21 different criteria that
were weighted by the militarys user community.
Atmospheric-pressure plasma (APP) ranked high in
most functional areas.
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The problems are energy efficiency, logistics,
size and cost.
All atmospheric pressure plasma requires high
voltage supply.
Some requires high power RF.
Some only operate in special carrier gas.
Most requires cooling
Most are not very reliable
Most are bulky
The ideal combination of high efficiency, operate
in one air, running in low DC voltage, compact,
long life and low cost does not exist.
Practical implementation for home land defense is
not yet possible.
We are building a unique plasma source using the
combination of MEMS and IC technology that will
satisfy this ideal plasma source requirement.
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Emergency protection application
A compact forced air plasma source coupled with
air filter can be used to create a positive
pressure personal protection zone
A low cost, bio/chem emergency protection garment
can be made.