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IEEE Nanomed 2009, October 18 - 21 , 2009 —Tainan, Taiwan
Nanoparticle Induced DNA Damage
Thomas Prevenslik
Discovery Bay, Hong Kong, China
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IEEE Nanomed 2009, October 18 - 21 , 2009 —Tainan, Taiwan
Introduction NPs offer significant technological advancements as
antibacterial agents in food processing, reducing infections in burn treatment, sunscreen skin lotions, and
treating cancer tumors.
However, NPs have a darkside
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Over the past few decades, experiments have shown NPs produce ROS of hydroxyl radicals that cause apoptosis/cell death and single and double strand breaks in the DNA.
ROS = Reactive Oxidative Species
IEEE Nanomed 2009, October 18 - 21 , 2009 —Tainan, Taiwan
Oxidative Stress Paradigm
ROS is correlated with the surface area of <100 nm NPs
Surface activity is the proposed ROS mechanism.
Problem – Coarse PM > 300 nm enhance ROS
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IEEE Nanomed 2009, October 18 - 21 , 2009 —Tainan, Taiwan
DNA Damage Levels
Direct DNA require at least photolysis at UV levels. The DNA ionization potential ~ 7.5 to 10 eV. Breaking
SS and DS in dry DNA ~ above 7 eV.
Indirect Hydroxyl radicals cause SS and DS breaks by chemical reaction ~ 5.2 eV break H-OH.
Most likely to DNA damage path.
Surface activity unlikely source of EM energy > 5 eV4
IEEE Nanomed 2009, October 18 - 21 , 2009 —Tainan, Taiwan
DNA Damage by EM Radiation
Experiments over pas 20 years show DNA damage by NPs that by conventional EM radiation
beyond the UV.
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mimics
IEEE Nanomed 2009, October 18 - 21 , 2009 —Tainan, Taiwan
Hypothesis
NPs in body fluids produce EM radiation beyond the UV that generates the ROS that provides:
Bactericidal action
But also damages the DNA
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IEEE Nanomed 2009, October 18 - 21 , 2009 —Tainan, Taiwan
QED induced EM radiation
Classically, heat (EM energy) is conserved by an increase in temperature.
But at the nanoscale, QM forbids an increase in temperature because specific heat vanishes.
QED allows heat to be conserved at the nanoscale by the emission of nonthermal EM
radiation
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IEEE Nanomed 2009, October 18 - 21 , 2009 —Tainan, Taiwan
QM Restrictions
cf Dn2 r hfEP
QED induces the creation of photons of wavelength by supplying EM energy to a box with walls separated
upon /2. For a spherical NP of diameter D having refractive index nr > 1:
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QM restricts the heat content of atoms depending on temperature and EM confinement given by the Einstein-
Hopf relation for harmonic oscillator
IEEE Nanomed 2009, October 18 - 21 , 2009 —Tainan, Taiwan
Einstein-Hopf Relation
0.00001
0.0001
0.001
0.01
0.1
1 10 100 1000
Wavelength - - microns
Pla
nck
Ene
rgy
- E -
eV
1
kT
hcexp
hc
E
9NPs
0.0258 eV Heat
capacity vanishes
IEEE Nanomed 2009, October 18 - 21 , 2009 —Tainan, Taiwan
QED radiation in NPs
• • • Specific Heat Vanishes
No Temperature change
EM
Emission
= 2Dnr
Molecular
Collisions
Laser/Solar/Supernova
Photons
Residual
Thermal
kT
Energy
Joule
Heat
NP
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IEEE Nanomed 2009, October 18 - 21 , 2009 —Tainan, Taiwan
NPs and Biological Cells
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Collision
DNA Damage
UV
H2OHydroxyl Radical
NP
Biological Cell Wall
NP
UV
IEEE Nanomed 2009, October 18 - 21 , 2009 —Tainan, Taiwan
Collisional Power
0.1
1
10
100
1000
0 500 1000 1500 2000
NP Diameter - D - nm
Col
lisio
nal P
ower
- Q
C -
nW
avag2
C N/MWm,m
kTpPD
32Q
Collision Power
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IEEE Nanomed 2009, October 18 - 21 , 2009 —Tainan, Taiwan
QED Photons and Rate
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0.1
1
10
100
1000
1 10 100 1000 10000
NP Diameter - D - nm
Pla
nck
Ene
rgy
- E P
- e
V
1.E+12
1.E+15
1.E+18
1.E+21
1.E+24
1.E+27E P
dNP /dt
QE
D P
hoto
n ra
te -
dNP /
dt.
Non-IonizeIonize
Silver nr = 1.35
CP
P Qdt
dNE Photolysis Power
IEEE Nanomed 2009, October 18 - 21 , 2009 —Tainan, Taiwan
PM Enhancement
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d
dUV
UV
NIRD
Collision
Collisions
DNA
DNA
IEEE Nanomed 2009, October 18 - 21 , 2009 —Tainan, Taiwan
PM Enhancement
1
10
100
1000
0 20 40 60 80 100
Fine NP Diameter - d - nm
Enh
ance
men
t Rat
io -
R
D = 1500 nm
D = 300 nm
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IEEE Nanomed 2009, October 18 - 21 , 2009 —Tainan, Taiwan
Conclusions NPs < 100 nm produce UV radiations act as bactericidal agents but also
damage DNA and increase the risk of further cancer.
NIR lasers are not necessary to kill cancers. The EM energy required to produce UV radiation is the thermal kT energy of surrounding solution
molecules that upon absorption is induced by QED to be frequency up-converted to UV levels.
The oxidative stress paradigm that DNA damage is caused by ROS produced proportional to the area of <100 nm NPs needs to be modified to include the
effect of larger 300-1500 nm PM.
Surface activity is an unlikely source of ROS
Sunscreens having NP < 100 nm NPs should be replaced by NPs > 100 nm
Silver NPs in limiting bacteria in food processing should cease immediately.
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IEEE Nanomed 2009, October 18 - 21 , 2009 —Tainan, Taiwan
Extensions Einstein’s Static Universe
Redshift in NPs means Universe is not expanding and dark energy does not exist.
TribochemistryRubbing of surfaces produces NPs that produce VUV to enhance chemical reactions
Gecko walking on walls and ceilingsSpatulae under index of refraction EM confinement produce electrostatic attraction
Unification of Static ElectricityRubbing of surfaces produces NPs that charge the surroundings.
Nanocatalysts and Chemiluminescence Gold NPs added to chemical reactants in solution enhance chemical reactions
X-rays from peeling Scotch TapeNPs that form as adhesive tears accumulates charge that at breakdown produces x-rays
Casimir forceEM confinement of BB thermal radiation in gap between parallel plates produces attraction
Etc…
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IEEE Nanomed 2009, October 18 - 21 , 2009 —Tainan, Taiwan
Questions & Papers
Email: [email protected]
http://www.nanoqed.org
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