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““Lighting the Way to Lighting the Way to NanoNano--Technology through InnovationTechnology through Innovation””
P.N.Prasad
NanomaterialsNanomaterials Based Nanotechnology toBased Nanotechnology toMeet the 21Meet the 21stst Century Technical ChallengesCentury Technical Challenges
The Institute for Lasers, Photonics and Biophotonics The Institute for Lasers, Photonics and Biophotonics www.photonics.buffalo.edu
Global Government Funding in 2008:
7.849 B$
US: 1.821 B$
China: 0.510 B$
Russia: 1.076 B$ EU: 2.440 B$
India: 0.050 B$
Korea: 0.350 B$ Japan: 1.128 B$
http://www.cientifica.eu/images/Whitepapers/nor-sample.pdf
Restof World:0.510 B$
NANOTECHNOLOGY: A GLOBAL PRIORITY
The Institute for Lasers, Photonics and BiophotonicsMultidisciplinary Frontier Research in Lasers, Photonics and Biophotonics
Extensive Research Facility ($26 million)
Education and Training Funded by NSF
Industrial Collaboration : Co-development, Industrial training, advanced testing
Technology Transfer : 5 spin off companies (Laser Photonics Technology, ACIS, Hybrid Technologies, NanoBiotix and Solexant Inc.)
International collaboration : Joint research, Student exchange, Joint workshop
The Institute for Lasers, Photonics and Biophotonics The Institute for Lasers, Photonics and Biophotonics www.photonics.buffalo.edu
3-D Bar Code
SOLEXANT CORPORATION
Subject of Global Priorities Subject of Global Priorities
Energy
Health Care
ChemicalAnd
BiodefenseEnvironment
Information Technology
NANOMATERIALSDendrimers
Prasad & Frechet
DURINT
eehν Block Copolymer Morphologies
Thomas, M.I.T.
Block-copolymers
Bates
Supramolecular
assembly
Self-assembly of dendrons
Percec
3 nm 7 nm3 nm 7 nm
Nanoparticles: QDs
Prasad
np no
ne
~ 200 nm
~ 10 nm
Nanocomposites
Prasad
Liquid Crystal nanodroplets
QDsPolymer
Prasad & Suga
Bridger-DNA
2D periodic arrays
Lineararrays
DNAduplex
Continuedarrays
Continuedarrays
=
O
O
O
O
NN
O
OO
O
O
O
HN
NH
DNA-NH2
DURNT KickDURNT Kick--Off Meeting at UB, Nov. 3rd 2001Off Meeting at UB, Nov. 3rd 2001Self-assembly on DNA template
Self-assembly
Fuel CellsSolar Energy
NanotechnologyNanotechnologyforfor
EnergyEnergy
Oil & Gas
Bio-fuelsHydrogen
Fuel
ThermoelectricPower
Solid StateBatteries
Nanotechnology for Solar Energy ConversionOur objective:
Hybrid nanomaterials‐based next generation flexible
solar cells for broad band solar harvesting
Buffalo TeamProfessor P. N. PrasadProfessor A.N. CartwrightProfessor D. WatsonDr. H.S. OhDr. J. SeoDr. S.J. KimDr. P. RodriguesMr. W.J. KimMr. D.H. Lee
International CollaborationProfessor K.S. Lee, KoreaProfessor D.H. Choi, KoreaProfessor L. Akcelrud, BrazilProfessor J. Dutta, ThailandProfessor A. Ho, Hong KongProfessor, A. Gomes, Brazil
Nanotechnology for Efficient Harvesting of Solar EnergyNanotechnology for Efficient Harvesting of Solar Energy
Current technologies need improvement in:• IR conversion• UV conversion
Carrier multiplicationby UV absorption in quantum dots
Bi-exciton
Hot Exciton
ħωc
2.6 2.8 3.0 3.2 3.4 3.6 3.8 4.0 4.2
0.5
1.0
1.5
2.0
2.5
3.0
3.5
Nor
mal
ized
Car
rier E
xtra
ctio
n
[Ele
ctro
ns/ P
hoto
ns]
Photon Energy/Eg
Sample #0510073_3Absorption Peak: 1670nmApplied Bias: 3V
S.J. Kim, P.N.Prasad et al, Appl. Phys. Lett. 92, 031107 (2008)
Nanophotonics
solution:3 nm 7 nm3 nm 7 nm
QD with tunable absorption
Photon Harvestingby IR absorbing QDs
Facilitated Charge separationBy conjugation to SWNT
Enhanced charge collection by high mobility organics
Quantum dotsfor harvestingIR photons
Cho, Prasad et al.,Adv. Mater. 19, 232 (2007)
Nanotechnology for UV Light HarvestingChallenges:
Extracting charge generated by MEGShort (ps) exciton lifetime vs. long (ns) charge transfer
timeSurface recombination by traps and defects on QDsControlling phonon dynamics and charge transferUV transparency of matrix for Quantum Dots (QDs)
Our Approaches:
Lateral patterning of QDs for perpendicular junction formation using t-BOC ligandsSurface modification to minimize defects and trapsFundamental investigation of charge transfer dynamics between QDs and other materials using spectroscopic studyLigand exchange to reduce charge transfer barriersIncorporation of Transparent Conducting Oxides
τET
= 0.84 μs
electroelectro
dede
λ
= 1.34 μm
++++ N)(
glassglassITOITO
pentacene PbSe
QD PVK
Example of IR Example of IR PhotodetectionPhotodetection Enhancement :Enhancement :Case of Case of PentacenePentacene as a coas a co--constituentconstituent
•• Soluble precursor to pentacene
• Dramatic enhancement of photoconductive efficiencyFrom 3% to 8%
Max EQE ~ 8% Max EQE ~ 8% in the IRin the IR
Choudhury, et al., Appl. Phys. Lett. 89, 051109 (2006).
Infrared Sensitization for PhotovoltaicsChallenges
:
Photon harvesting in IR: Small absorption coefficient Need for a compatible low bandgap polymer matrixDevice Optimization: Low bandgap Low VocCreating environmentally friendly nanocrystals to
replace PbSe and PbSPhoto-enhanced oxidation of QDs: Short cell lifetime
Our Approaches
:
Plasmonic enhancement using metallic nanostructures and binary metal:semiconductor nanostructures
increase absorption Low bandgap polymers for better band alignment to QD
bandgapOptical Tuning of QDs combined with multi-junction solar
cell structuresNew “Green” IR absorbers (e.g., Cu2S)Oxygen free processing combined with encapsulation
PbSe
QDs
400 500 600 700 800 900 1000 1100 1200 1300
0.1
0.2
0.3
0.4
0.5
0.6
0.7
Abs
orba
nce
(a.u
.)
Wavelength (nm)
New IR absorbing nanoparticles
Optical and electrochemical properties of PCPDTBT
NSN
Br BrSS
NSN
n
PCPDTBT(Blue solid)
SS
+
Bu3Sn SnBu3
Polymerization(Stille coupling)
400 500 600 700 800 900
0.0
0.1
0.2
0.3
Abs
orba
nce
Wavelength (nm)
PCPDTBT film
Molecular weight Abs. max. HOMO LUMO Band gap
Mn = 26 kDaMw = 50 kDa
720 nm (film) -4.96 eV -3.60 eV
1.36 eV (EC)1.53 eV (OP)
NIR absorption
Development of efficient NIR polymer;Synthesis of the low-band gap polymer (PCPDTBT)
We can modify the polymer structures to obtain various polymer structures with tunable band gap(700-1000 nm)
NX
N
NY
N
RmSS n
R = Aromatic group (m=1,2) X = Y = S or Se
PCPDTBT:PCBM
ITOPEDOT
LiF/Al
500 600 700 800 9000.0
0.1
0.2
0.3
0.4
0.0
0.1
0.2
0.3
0.4
Absorbance
Spe
ctra
l res
pons
ivity
(A/W
)
Wavelength (nm)
PCPDTBT:PCBM (1:3.6)
Photovoltaic performance (preliminary result)
-0.2 0.0 0.2 0.4 0.6 0.8-10
-8
-6
-4
-2
0
2
4
Cur
rent
den
sity
(mA
/cm
2 )
Voltage (V)
AM 1.5G AM 1.5G through 715 nm long pass filter
Voc Jsc FF PCE
AM1.5G
0.65 8.17 0.37 1.96
Filter 0.62 2.69 0.40 0.68
NIR contribution: ~34.6%
CdSe multipod CdTe QD PbSe QD CdSe QD
Photo-patternable
Nanocrystal
Quantum Dots and Multipods
Current-voltage curves (a) at r.t. for an array of CdTe
NCs
in the dark and during excitation with white light. MSM device structure (b) for photoconductivity measurement.
Typical structure and components of DSSC
1. Absorption
2. Electron Injection
3. Regeneration
‐
Reaction at Cathode
Reactions at Anode
4. Re‐reduction of electron donor
Dye Sensitized Solar Cells (DSSC)
Operation Cycle
Counter Electrode
TCO Coating (FTO)
Pt
Glass
Glass
Electrolyte
Transparent Conducting Oxide Coating (FTO)
Photo-Electrode
Courtesy J. Dutta
Technical Challenges1.
Light Harvesting by QDSSCs2.
Electron injection between QDs
and the metal oxide substrate; hole injection from electrolytes (or hole transporting layers) to QDs.
3.
Charge-collection efficiencies of QDSSCs
and the problem of bulk electron transfer processes.
4.
Photostablity
and Longevity of QDSSC.
Our Strategy1.
High surface loading of QDs; near IR absorbing nanocrystals; plasmonic
enhancement of photoexcitation.
2.
Optimize interfacial charge transfer by surface functionalization
and better interconnectvity.
3.
Improve electron transport by using nanowires and hole transport
by using medium with high hole mobility.
4.
Surface functionalization
and protective coating.
Quantum Dot Sensitized Solar Cell Challenges
0.0 2.0x10-6 4.0x10-6 6.0x10-6 8.0x10-6
-0.020
-0.015
-0.010
-0.005
0.000
Abs
orba
nce
chan
ge
Time (s)
CdS-S-(CH2)15-CO2-TiO2 CdS-S-(CH2)5-CO2-TiO2 CdS-S-(CH2)2-TiO2
Distance‐dependent electron injection
Optimizing Charge Transfer in Composite SystemsMaterials assembly: modification of ligands
CdS(e)
TiO2R
O
OH + TiO2RO
O TiO2S R
O
OCdS(e)
AHSHSHO
H2O
B
Electron injection
hν
Dibbell, R.S.; Soja, G.R.; Hoth, R.M.; Watson, D.F. Langmuir 2007, 23, 3432-3439 Mann, J.R.; Watson, D.F. Langmuir 2007, 23, 10924-10928
400 500 600 700 800
-0.020
-0.015
-0.010
-0.005
0.000
Abs
orba
nce
chan
ge
Wavelength (nm)
CdS CdS-S-(CH2)2-CO2H CdS-S-(CH2)2-CH3 + TiO2 CdS-S-(CH2)2-CO2-TiO2
λpump
= 415 nm (6-8 ns)τdelay
= 160 ns1:1 THF:EtOH
Nanosecond transient absorption spectra
Dibbell, R.S.; Watson, D.F. J. Phys. Chem. C 2009, 113, 3139-3149
Nano‐wire
CB
VB
Eg
ee
CdSQD
Cu2
SQD
Direct and Fast transport electron in DSSC by using Nanowires
hν
Bandgap
Alignment
for Carrier Cascade
QD‐sensitized nanowires: directional charge transport
Collaboration: Prof. J. Dutta
(Thailand), Prof. A. Ho (Hong Kong), Prof. A. Gomes (Brazil)
400 450 500 550 600 650
0.0
0.5
1.0
1.5
Abs
orba
nce
Wavelength (nm)
Novelty:•
Heterolayers
of QDs
via in situ
precipitation or
surfactant‐mediated
self‐assemblyObjectives:•
Enhanced light‐harvesting efficiency
(LHE)•
Cascading interfacial electron transfer
Heterolayer
QD‐sensitized solar cells
CdS‐TiO2
: optimizing fabrication, LHE 400 450 500 550 600 6500.0
0.5
1.0
1.5
Abs
orba
nce
Wavelength (nm)
TiO2 TiO2-CdS(6) TiO2-CdS(6)-CdSe(4)
In situ
precipitation
Heterolayer
QD‐sensitized solar cells
0.0 0.1 0.2 0.3 0.4 0.5 0.6-8
-6
-4
-2
0
Cur
rent
den
sity
(mA
cm
-2)
Voltage (V)
TiO2 TiO2-CdS(6) TiO2-CdS(6)-CdSe(4)
Jsc
= ‐6.4 mA
cm ‐2
Voc = 0.522 VFF = 0.41PCE = 1.4%
Removal of CO2
from Natural Gas
High porous matrix(proprietary materials)
Nanoparticle coated porous matrix
Dip c
oatin
g
CO2
storage platform
CO2
Nanoparticle CO2
scavenger(proprietary chemistry)
CO2
A Commercial Opportunity
Cancer
Aging Obesity
Addictions
InfectiousDiseases
Genetic Disorders
Current and Future Health Care Challenges
Health and Wellness through Life Span to Increase the “Quality of Life”
Disease PreventionEarly detection of disease Effective therapy (personalized)Post therapy/surgical assessmentCapacity to monitor therapeutic efficacy
Nanotechnology solution:NANOMEDICINE
Tailoring of Nanoparticle Platform
• Chemical “make-up” (inorganic; organic; hybrid)Single or multimodal imaging
• Shape (dots; rods; multipods)Spectral characteristics (controlled excitation/ emission)
• Size (1- 100 nm)Spectral characteristics, circulation control, biodistribution
• Porosity controlLoading/release of payloads
• Surface charge (positive, negative, neutral)Targeting agent coupling site, payload stability
• Surface characteristics (hydrophilic; hydrophobic)circulation control; payload stability
• Surface coating (organic; protein; nucleic acid)Biotargeting; circulation control; biodistribution; payload stability, controlled release
Nanotechnology-
based In Vitro Diagnostics
TORCH* Infections
Malaria
Influenza(Bird Flu)
Tuberculosis
HIV, HPV, Hepatitis B
Meningitis
*TORCH: Toxoplasmosis, Other agents (eg. Chicken pox, human parvovirus), Rubella, Cytomegaloviruse, Herpes simplex virus or HIV
Collaboration with Center for Disease Control, Atlanta
A Commercial
Opportunity
•
Semiconductor nanoparticles
with unique, tunable optical properties•
Highly photostable•
Narrow, symmetric emission spectra•
Ease of bioconjugation•
Ability for multiplexed analysis
Quantum Dots: New generation Diagnostic probes
lysine
Size tunable emission following illumination with UV Light
3 nm 7 nm3 nm 7 nm
Y
Y
Y
Y
Antibody forbiorecognition PEG for enhanced
colloidal stability
J. Qian, P.N.Prasad et al, J. Phys. Chem. B. 2007, 111 (25), 6969.
ApplicationsIn vitro ImagingIn-vitro DiagnosticsTargeted Drug deliveryTheranostics
InIn--VitroVitro Imaging Using Imaging Using NanoemittersNanoemitters
for Early Detection of Diseasesfor Early Detection of DiseasesUsing Cellular SignaturesUsing Cellular Signatures
Technical Challenges Our Approach
Optical TransparencyNear-IR emitting Nanoparticles
Surface Functionalization
for aqueous dispersions, while retaining high quantum yield
Core-Shell Structures, Surface functionalization
and coating
CdTe
ZnTe Cysteine
Reduction of Cellular Toxicity
Surface Functionalization
and Biocompatible Coating
Targeting group
PEG group
CdTe ZnTe
Process Control for Uniformity and Scalability, Green Chemistry
New Aqueous SynthesisCadmiumPrecursor
TelluriumPrecusor
Stabilizing ligand
↑100°C
In Vitro NIR Imaging using CdTe
QDs
In vivo
NIR-NIR optical bioimaging data: Ex = 975 nm, Em = 800 nm
In Vitro NIR Imaging using up‐conversion nanoparticles
Confocal microscopy
image of live cancer cells
treated with NIR QDs.
Immunomicrobeads
captureanalytes
(soluble proteins)
Flow Flow CytometryCytometry: Rapid, multiplexed detection of trace amounts : Rapid, multiplexed detection of trace amounts of diseased cells/ protein biomarkers from biological samplesof diseased cells/ protein biomarkers from biological samples
(2) Lasers illuminate the dyes generating fluorescence
(1) Beads travel in a very narrow stream (thousands per sec) (4) Results are analyzed
(3) Multiple Signals are collected/detected/digitized
Microbeads
coated withcapture antibody
Bead A
Bead B
Bead C
QD-detection antibodieslabel the capture analytes
A Commercial
Opportunity
Technical challengesTechnical challengesEnhanced tissue penetration by light
Delivery across biological barriers (e.g. blood-brain barrier, liver, lung, etc.) andreduced nanotoxicity
and inflammatory response
Biodegradation and excretion of nanoparticles
Our strategiesOur strategies
Multimodal Imaging (e.g. PET, SPECT/CT, MRI and luminescence)
Reduction of hydrodynamic size of nanoparticles; modification of surface of nanoparticles
with long circulation “biocompatible”
polymer coating; conjugation of targeting biomolecules
to the nanoparticles.
Engineering biocompatible, stable, non-heavy metal based, and PEGylated
nanoparticles
(e.g. silicon).
Challenges and Solutions for In Vivo Nanotheranostics
Use of light in the biological window of optical transparency (~650 –
900 nm)
Molecular cellular morphological imaging and analysis
Near infrared phosphorescent polymeric nanomicelles: efficient optical probes for in vivo tumor imaging and detection
Biocompatible Silicon Quantum Dots as Biological Fluorescent Labels
Silicon nanoparticlesproduced by Laser-Driven
Pyrolysis
Process
Etching with
HF/HNO3
Etching with
HF/HNO3
Etching with
HF/HNO3
Hydrogen terminated
Silicon particles
Diff
eren
t co l
ors
of p
hoto
l um
ines
cenc
e
Erogbogbo, Prasad et al. ACS Nano
2008, 2(5), 873-876.
Si only
Si-RGD
Erogbogbo, Prasad et al. Under review in PNAS (USA). 2009
Tumor targeting with silicon NPs
ORMOSIL based multimodal nanoparticle platform
In-Vivo DiagnosticsMultimodal Nanoplatforms
for Medical Imaging
PET124I labeled-ORMOSIL
MRIGd-doped Nanophosphor
OpticalGd-doped Nanophosphor
M. Nyk, P.N.Prasad et al, Nano Letters, 2008, 8(11):3834; R. Kumar, P.N.Prasad et al. Avd. Func. Mater. (In Press, 2008)
SPECT/CT125I labeled-ORMOSIL
Nature Defense Mechanisms
Biological Barriers
SkinProtects against
environmental insult and microbial invasion
Mucosal barriersProtects surfaces against
environmental insults (chemical, bacterial and
particles)
Blood Brain BarrierProtects brain by
regulating the entrance of chemical and micro/nano
materials
Reticulo-Endothelial Barrier (RES)
Captures foreign materials for removal by liver and spleen
Time dependent liver clearance of PEGylated
ORMOSIL nanoparticles
Liver
AbdominalCavity
Day 0 Day 3 Day 7
Day 7(Dissected mouse)
Liver
Intestine
Stomach
Liver
Spleen
Dissected Mouse
Day 0 Day 7
Strategies for overcoming RES barrier
•
Encapsulating molecules within ultrafine nanoparticles
(diameter below 50 nm)
•
Modulation of surface charge of nanoparticles: Neutral or moderately negative surface charge favors RES escape
•
Coating nanoparticle surface with PEG or any other inert polymer
UPPER LAYERBLOOD END
DAY1 DAY2 DAY3 DAY4
DAY1 DAY2 DAY3 DAY4
LOWER LAYERBRAIN END
Gold nanorod
(GNR) –
fluorescent siRNA
Nanoplex:Optical tracking of time dependent transport across BBB
Confocal images showing enhanced staining of cells with time,thus indicating BBB transport
QR-RGD
QR only
In vivo diagnostics: Early detection of cancerTumor targeted delivery of RDG peptide conjugated QRs
following systemic injection
Tumor
Tumor
Yong, Prasad et al. Under review in ACS Applied Materials and Interfaces. 2009
PEGylatedPhospholipid molecule
Biodegradable PLGA molecule
Doxorubicin
Biodegradable Nanoparticles
in Imaging and Drug delivery
Cancer nanotechnologyTargeted delivery ●
Controlled release ●
Multimodal therapy ●
Real time monitoring
With Uttam
Sinha, M.D.Univ. of Southern California
Gene TherapyHead & Neck, Lung cancer
Gold NanorodGold Nanorod
With McMaster Univ.
Neutron capture therapyBrain, prostate cancer
NaYF4: Tm/GdNaYF4: Tm/Gd
With Anirban
Maitra, M.DJohns Hopkins Univ. Medicine
ChemotherapyPancreatic, Prostate cancer
lysine
YY
YYlysine
YY
YYlysinelysine
YY
YYlysine
YY
YYlysine
YY
YYlysinelysine
YY
YY
Magnetic therapy
US patent No. 6,514,481
Nanoclinic
Breast & Oral cancer
With Ravi K Pandey, Ph.D.Roswell Park Cancer Institute
PSPSSi
O
OO
I
SiO OI
ORMOSIL nanoparticle
SiO
OO I
PSPSSi
O
OO
I
SiO OI
ORMOSIL nanoparticle
SiO
OO I
Photodynamic therapyCervical, skin cancer
3 product familiesnanoTherapeutics30nm silica based Source Indication
nanoMag
nanoPDT
nanoXRay
• MRI
• Lasers
• X-Ray
Local treatment forsuperficial & cavity cancer
Local treatmentin the irradiation area
Local treatment and potentially whole body
A new dimension in cancer care
Paris, France http://www.nanobiotix.com/
Nanoplex
Gene delivery using nanoparticles
•Electrostatic gene condensation•Efficient cellular entry•Non-toxicity•High gene expression/silencing
Nucleus
Endosome
Protein
Nanoplex
Nucleus
Endosome
Protein
Nanoplex
Gene Augmentation e.g. CFTR gene in Cystic Fibrosis Gene Silencing e.g. Oncogene in Cancer
Nucleus
Endosome
Protein
Nanoplex
Nucleus
Endosome
Protein
Nanoplex
Nanoparticle mediated gene silencing: Implications in drug addiction therapy
Gene silencing efficiency of gold nanorod(GNR)-siRNA
nanoplex
is higher than that obtained using commercial agent (siPORT)
0
20
40
60
80
100
siPROT-neg control siRNA(200pM)
GNR 640-DARPP-32 siRNA(200pM)
siPROT-positive controlDARPP-32 siRNA (200pM)
% C
hang
e in
DA
RPP
-32
expr
essi
on
A.C. Bonoiu, P.N. Prasad, et al. Submitted to Proceedings of The National Academy of Sciences of USA, (2008) Collaboration with Stanley M Schwartz, M.D., Buffalo General Hospital
Slow Release of active principles
For Maximizing Efficacy
Nanofibers
for ImprovedTopical Formulations
Nanotechnology for Cosmetics Nanocosmetics
*
*US nanocosmetic
market in 2001 19 $B was extended at 58 $B in 2008
Deep Skin Penetration of
Anti-aging nanocosmetics
Nano-stabilized Botanicals Enabling
New Class of Cosmaceuticals
Nanoencapsulated
ScentsFor Long Lasting perfume
NanotechnologyFor
Information
Communication:
•
Reconfigurable Photonic
Crystals
•
3D Plasmonic
Guiding and Routing
Network
Displays(Organic Displays:
OLED, PLED)Storage:•
3D Two-Photon Storage•
Holographic Storage
Processing:•
Electro-optic Processing Using Supramolecular
Structures
and Nanocomposites
•
Electrically and Optically Switchable
Photonic Crystals
Nanotechnologyfor
Environment
Rapid in-field and remotemonitoring
Nanoporous
membranetechnology for
decontaminationand purification
Nanoparticle basedcapture platform
Nanostructured
sensorand device platforms
Nanotechnologyfor
Chem/Bio Defense
Rapid in-field and remote detection
Nanomedicine
based
rapid medical responseNanostructured
capture anddetoxification platform
Rapid disseminationof information
Nanostructuredsensor platforms
Fundamental and Technical Challenges for Nanotechnology
•
Fundamental Understanding of Physics at Nanoscale
(Electronic, Photonic, Magnetic)
•
New Physical and Chemical Processes
•
Manipulation of Excitation & Dynamics on Nanoscale
•
Control of Interfacial Interactions
•
Device Integration of Nanostructures
•
Nano-toxicity
NanotechnologyNanotechnology
• A new Multidisciplinary Scientific Research Frontier
• Ripe for Technological Innovation and Commercial Opportunities
• Destined to create Immense Societal Impact
Acknowledgements
Prof. A.CartwrightDr. K.TramposchDr. E.J. BergeyDr. G.S.HeDr. H. PudavarDr. K.T. YongDr. T. OhulchanskyyDr. I. RoyDr. S. KimMr. J. QianDr. H. DingDr. A. KachynskiDr. A. KuzminDr. A. PlissDr. A. BonoiuDr. D. BharaliDr. R.KumarDr. S. MahajanDr. J.W. SeoMr. S.J. KimMr. S.S. Kim
AFSOR (Dr. Charles Lee)National Cancer InstituteNational Science FoundationAFRL (Dr. Augustine Urbas)OISHEI FOUNDATION
Outside Collaborators
Prof. R. PandeyProf. A. OseroffProf. M. StachowiakProf. K.S. LeeProf. M. SamocProf. P. KnightDr. P. WallaceDr. A. MaitraDr. S. SchwartzDr. U. SinhaProf. J. DuttaProf. A. Ho Prof. A. Gomes
The Institute for Lasers, Photonics and Biophotonics The Institute for Lasers, Photonics and Biophotonics www.photonics.buffalo.edu
““Lighting the Way to Lighting the Way to NanoNano--Technology through InnovationTechnology through Innovation””
P.N.Prasad
NanomaterialsNanomaterials Based Nanotechnology toBased Nanotechnology toMeet the 21Meet the 21stst Century Technical ChallengesCentury Technical Challenges
The Institute for Lasers, Photonics and Biophotonics The Institute for Lasers, Photonics and Biophotonics www.photonics.buffalo.edu
•
Theory: multiscale
modeling (molecular, nanoscopic, bulk )
•
Synthesis and materials characterization•
Synthesis and surface functionalization
of nanoparticles•
Synthesis of functional organic monomers, oligomers, and polymers•
Assembly of nanoscopic
components into hybrid materials
•
Comprehensive characterization of relevant physical and chemical
processes•
Characterization of materials and surfaces•
Spectroscopy on multiple timescales•
Femtosecond-to-picosecond: electron injection dynamics•
Nanosecond-to-microsecond: electron injection yields, charge-
separated-state lifetimes
•
Device fabrication & characterization:
I-V measurements, short-circuit photocurrent action spectra
Nanotechnology for Solar Energy Conversion
Our capabilities:
A NEW APPROACH:Optical IR to visible up-conversion in RE nanoparticles
for solar cells
500 750 1000 1250 1500 1750 20000.0
0.2
0.4
0.6
0.8
1.0
1.2
[A.U
]
Wavelength [nm]
Solar Spectrum Polymer absorption
(P3HT/PCBM)
Reusable Energy by up-convertgin
Device Structure usingReflection Hologram
hν
hνhν’
Photovoltaic Cell
TPA Up‐Converting Layer
Reflection Hologram
Visible Abs. & IR Trans.
Up‐converting using IR
Reflection for IR & hν’
Upconverting
nanoparticle layer
980 nm
Excitation
Yb,Tm:NaYF4Yb,Er:NaYF4
ChloroformWater
50 nm
Up-converting nanoparticles
Engineering Fabrication and Integration of Nanostructures
A Commercial Opportunity
Photopatterning of Nanoparticles (Prasad, Propriety Technology)
Glass substrate Spin casting of NCs Photopatterning the film through a mask
UV
Develop the patterned filmUsing proper solvent
Photomask
NC
NC
Photopatterned
QDsGlass substrate Spin casting the NCs Photopatterning
the film Develop the patterned film
W.J. Kim, P.N. Prasad et al, Nano Lett., 2008, 8, p. 3262
UV
Photomask
100 μm 100 μm
Near IR
Up-conversion
Security Card
Security Application
Collagen
Gold nanorods/MMP’s
inhibitors
Collagen Type IIIBasal expression
Gold nanorods/siRNA
Castaneda L. et all.2008 Prasad et all. 2009 unpublished data
Gold nanoparticles/peptides
Personalized skin treatment with biocompatibile materials
Collagen Cross-Linking with Au Nanoparticles
Collagen Type IIIRecovered
Nanocosmetics present and future
•Skin Surface protection
• Skin surface penetrationRehydratation
/remodelation
•Skin treatment deep dermal/transdermal
deliver of therapeutic agents
The skin model ‘in vivo’In vitro skin model for testing
nanocosmetics
“Lighting the Way to Nano-Technology through Innovation”Slide Number 2Slide Number 3Slide Number 4Slide Number 5Slide Number 6Slide Number 7Nanotechnology for Efficient Harvesting of Solar EnergySlide Number 9Slide Number 10Slide Number 11Slide Number 12Slide Number 13Slide Number 14Slide Number 15Slide Number 16Slide Number 17Slide Number 18Slide Number 19Slide Number 20Slide Number 21Slide Number 22Slide Number 23Slide Number 24Slide Number 25Slide Number 26Slide Number 27Slide Number 28Slide Number 29Slide Number 30Slide Number 31Slide Number 32Slide Number 33Slide Number 34Slide Number 35Slide Number 36Slide Number 37Slide Number 38Slide Number 39Slide Number 40Slide Number 41Slide Number 42Nanoparticle mediated gene silencing:�Implications in drug addiction therapySlide Number 44Slide Number 45Slide Number 46Slide Number 47Slide Number 48Slide Number 49Slide Number 50Slide Number 51“Lighting the Way to Nano-Technology through Innovation”Slide Number 53Slide Number 54Slide Number 55Slide Number 56Slide Number 57