2013 colombiausanano...arvind raman mechanical engineering, birck nanotechnology center, purdue...
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2013 ColombiaUSANano
1
14 Invited speakers from the US representing
Rice, Cornell, Univ. Illinois, Northeastern, UT San
Antonio, Purdue, and CTO of GE (Energy Systems)
Panelists
Carlos Fonseca, the director of Colciencias
Vice-rectors of research of U. de los Andes, U.
Nacional, Universidad EAFIT, Universidad de
Antioquia, Universidad del Valle, Universidad
Pontificia Bolivariana
Alex Orr, US embassy
Neil Vallesteros, ONR-global
Arden Bement, Purdue’s Global Policy Research
Institute
Ann Mason, then director of Fulbright-Colombia
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Outcomes2013 ColombiaUSANano Univ de los Andes 2017 USAColombia Nano
Univ Antioquia- Northeastern University partnership on
nanomedicine
Uniandes-SENA-Penn State collaboration on nanotech
education
Nacional-U. Texas collaboration on nanoparticles
Sumicol Corona- Univ of Illinois collaboration on nanoceramics
Universidad Pontificia Bolivariana Nanotechnology Engineering
Program launched
SENA workshop on nanotechnology with Purdue
The Nanotechnology Center effort was been taken up by RutaN
– national policy for nanotechnology infrastructure proposed
Proyecto Interchange
2
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Advances in Atomic Force Microscopy for the Characterization of Complex Materials and Live Cells
Arvind Raman
Mechanical Engineering, Birck Nanotechnology Center, Purdue University
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Top ten discoveries in materials
science in the past 50 yearsMaterials Today, vol 11, 2008, P. Ball, Nature Materials, 2008
The International Technology Roadmap for Semiconductors
Scanning probe microscopes
Giant magnetoresistive effect
Semiconductor lasers and light-emitting diodes
National Nanotechnology Initiative
Carbon fiber reinforced plastics
Materials for Li ion batteries
Carbon nanotubes
Soft lithography
Metamaterials
3
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4
Bio-AFM
Andor spinning disk confocal
+Asylum MFP3DCypher Asylum
Agilent 55002 Nanotec Electronica’s
Polytec LDV MSA400
Virtual Environment for
Dynamic AFM (VEDA 2.0)
AFM Research Facilities
Atomic resolution TM-AFM
mica and Calcite in water
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nanoHUB resources for AFM
5
D. Kiracofe, J. Melcher, S. Hu and A. Raman ~2000 users; ~15,000 simulations • Used by all major AFM companies• Air/vacuum/water simulations• AM/FM-AFM, bimodal
Virtual environment for dynamic AFM (VEDA) is a open-source, free cyber-infrastructure enabled online simulator for AFM available on nanohub (www.nanohub.org). VEDA funded by Network for Computational Nanotechnology and Dow AFM division
I have been using VEDA …
… found it to be extremely useful.
… enabled us to make better choices
in designing new probes.
… used VEDA as a check on other
calculations.
Roger Proksch, President
Asylum Research
Colombian PI’s such as Alba Avila also deploy tools on nanoHUB
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AFM Trends
Quantitative physical property mapping
Combined instruments
Sub-surface imaging
High-speed imaging
Higher-resolution imaging
6
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Biophysical properties of cells are
connected to biochemical state Example-Motility requires the
rearrangement of cytoskeletal networks in
the cell
Motility is driven by extension of
lamellipodia at the front of the cell and
retraction of trailing edge driven by actin
filaments and dynamic microtubules
7S. Etienne-Manneville (2013) Annu. Rev. Cell Dev. Biol. 29: 471-99.
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Methods to probe live cell mechanics
8
Bao,Espinosa, et al. Experimental Mechanics, 2009
AFM is unique in its capability to map cell properties on a substrate
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Bacteria
Surface tension due to turgor pressure
Bending stiffness of cell wall
Visco-elasticity
Properties are heterogeneous
Applications to new antimicrobial drugs
9
Bacterianamehere.pbworks.com Mammalian eukaryotic cells
Viscoelasticity
Adhesion
Osmotic pressure
Properties are heterogeneous
Applications to early diagnosis
of cancer, understanding the
mechanical action of medicine
and fundamental cell biology
www.nih.gov: blue- microtubules, red- intermediate
Filaments , green- actin filaments
Mapping local properties of living cells
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How to measure live cell mechanical properties with the AFM?
10
Force distance curves at a pointCross et al, 2007, Iyer et al Nature Nanotechnology, 2009
Point by point force distance curves (force volume)
Radmacher et al, Micron 2012
- Low resolution (~ 32 by 32) , Low speed ~ 100’s of pixels a minuteNormal vs malignant thyroid cell maps
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Our approach- multi-harmonic AFM
Use high frequency, directly excited, resonant probes
scanning over sample at high speed
Observe changes in harmonics to map local mechanical
properties (viscoelasticity) – Multiharmonic AFM
Use harmonic balance to determine local properties
>10,000 pixels per minute throughput
11Raman, Trigueros, Cartagena et al, Nature Nanotechnology, 2011
i
β
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Example 1: fibroblasts
12Raman, Trigueros et al, Nature Nanotechnology, 2011
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Organ: Mammary gland; breast
Disease: carcinoma
Derived from metastatic site: Pleural effusion
Cell Type: Epithelial
MDA-MB-231 cell
Example 2: Carcinoma cells (~20 min)
Syk EGFPNucleusTubulin
Collaboration with Dr. R. Geahlen and M. Krisenko, Purdue Cancer Center
to understand the mechanobiology of Syk tumor suppression
No Syk
expressed
Low Syk
induction
Krisenko, Cartagena, Raman, Geahlen, “Nanomechanical property maps of breast cancer cells by multi-
harmonic atomic force microscopy reveal Syk-dependent changes in microtubule stability mediated by
MAP1B”, Biochemistry, 2014
Dr. R. Geahlen
13
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Boosting speed (~1 min., 256 by 256 pixels, 10,000’s pixels a minute)
Cartagena, Raman et al., NPG Scientific Reports, 2015 14
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Cartagena, Raman et al., NPG Scientific Reports, 2015
Nanomechanical kinetics of Syk
knockdown on breast cancer cells
A0
EstorageEloss
d0
15
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3T3 fibroblasts
CO2-independent
medium, 37°C
Cantilever (BL-TR-
400PB) with a spherical
probe (5 μm diameter);
k = 0.03 nN/nm;
Scanner displacement
rate: 2 μm/s
Z-axis
Force-displacement curve
Z-a
xis
How to extract viscoelastic parameters directly from the force curves?Efremov, Raman et al, Measuring nanoscale viscoelastic parameters of cells directly from AFM force-displacement curves, in review Scientific Reports, 2017
Quantifying viscoelastic relaxation of live cells rapidly
16
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Combined fluorescence and AFMAFM
head
Spinning disk
confocal
(SDC)
microscope
Measuring cell relaxation during nano-indentation
by staining of actin cytoskeleton with SIR-actin
probe in MDA-MB-231 cells
X-Y
Z-Y
17
Z-Y section X-Y section
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AFM Trends
Quantitative physical property mapping
Combined instruments
Sub-surface imaging
High-speed imaging
Higher-resolution imaging
18
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Polymer based nano-composites use nano-fillers
CNT’s, graphene, Nanoparticles of silica, clay, Ti02, iron oxide
Applications: Sensors, transparent electronic applications (touch screen
displays), flexible energy storage devices (supercapacitors, batteries,
solar cells), Antimicrobial films in food packaging, Filtration/separation
membranes
19
Scalable manufacturing of nanocomposites
Supercapacitor based on aligned
MWCNT/PANI composite films Lin, H.
et al. Scientific Reports 3, 1-6 (2013).
CNT thin-film transistors on a flexible and
transparent PEN substrate. Sun, D. et al.
Nature Nanotechnology 6, 156-161 (2011).CNT based bulk-heterojunction PA layer based on SWCNT
networks , Kymakis, Amaratunga, APL 80(1), 2012
CNT based electrode layer
Rowell et al. , APL 88(23), 2006
Polyimide film with dispersed graphene
micro-gravure coated on PETR2R microgravure and slot-
die system from MIRWEC
Roll to Roll
Systems
Opto-electro
nics
Drug Delivery Systems
Smart Packaging
Energy Generat
ion/ Storage
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20H. C. Anderson, "Prinsessen paa Ærten”, 1835
Dispersion and connectivity of percolating networks of CNT’s
fullerenes, graphene, are difficult to judge other than by bulk
measurements. Can AFM help?
Is it possible to see
underneath the surface?
AFM for sub-surface nanometric imaging?
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Electrostatic and stress fields probe
the sub-surface
21
dC/dZ
kcontact
Kelvin Probe
Force Microscopy
Contact Resonance AFM
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22
0D: Barium titanate / polydimethylsiloxane
(BaTiO3/PDMS)1D: Single-walled carbon nanotubes /
polyimide (SWNTs/PI)
2D: Reduce graphene oxide / polystyrene
nanocomposite (RGO/PS) Nano-composite
ComponentsProperties
0D
PDMS Polymer, Insulator,
εr = 2.3 – 2.8
BaTiO3 Ceramic, ferroelectric
εr = 1200 (20°C, 1kHz)
1D
PI Polymer, insulator
εr = 4
SWNTs Semiconductor or metallic
2D
PS Polymer, insulator
εr = 2.4 – 2.7
RGO Carbon-based, conductor
2nd harmonic KPFM
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Comparative studies of 2nd harmonic
KPFM and CR-AFM
23
M. Cadena, et al., accepted, App. Phys. Lett, 2016
M. Cadena, A. Raman, et al. Nanotechnology, 24 (13): 135706, 2013
A. Castaneda, A. Avila, A. Raman, ACS Nano, 2014
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24
Computer-aided tomography
M. Cadena, et al., accepted, App. Phys. Lett, 2016
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25
Region 1 Region 2
Computer-aided tomography
M. Cadena, et al., accepted, App. Phys. Lett, 2016
A. Castaneda, A. Avila, A. Raman, ACS Nano, 2014
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AFM Trends
Quantitative physical property mapping
Combined instruments
Sub-surface imaging
High-speed imaging
Higher-resolution imaging
26
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27
E, s, h, H, Fad
=10MPa, 2 nN …
E, s, h, H, Fad
=10kPa, 3 nN …
Thank you for your attention!
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Mapping local properties of viruses
Heterogeneity of material properties of viruses is due to the
intrinsic variation in the viral shells due to assembly of different
protein subunits, and due to the subsurface DNA structure
Elasticity, electrostatics, hydration forces, adhesion
Important for
Templating nanomaterials
Design virus mimmetic nanocontainers
Biophysics of viral infection 28
Eukaryotic virusesBacteriophages
CA B
25 nm
DNA layers
DNA stretchestail
pore
DNA
D
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Bacteriophage ɸ29 Mature Virion
TailCollar
Capsid
29
Heterogeneities in material properties maps are
due to variations in assembly of protein
subunits in the viral capsid, collar and tail knob
and subsurface DNA structure.
Cartagena, Hernando-Pérez et al., RSC Nanoscale 2013
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dAFM sub-surface imaging methods Dynamic AFM (repulsive regime)
Near surface
Needs large indentations on the surface
For soft materials
Ultrasound transmission using heterodyning
(Briggs, Kolosov, Cuberes, Tetard, Passian,
Thundat, Campbell, Arnold etc.)
Electrostatic methods
Electrostatic force gradients are modulated by local
dielectric properties
Local dielectric properties depend on sub-surface
properties
Can electrostatic/KPFM methods be used for sub-
surface imaging of nano-composites?
30Jespersen and Nygard APL, 2007; Zhao et al Nanotechnology, 2010
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Sub-surface imaging
31
How deep can we see?
What limits the resolution?
Non-destructive 3D Tomography?M. Cadena, A. Raman, et al. Nanotechnology, 24 (13): 135706, 2013
A. Castaneda, A. Avila, A. Raman, ACS Nano, 2014
M. Cadena, et al., accepted, App. Phys. Lett, 2016
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Layered sample analysis
Contrast can be seen down to 400nm32
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Computational analysis
Field spreading limits resolution
Can computations be used for 3D tomography?
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Interaction forces in dynamic AFM
34
Each model has a small set of parameters describing physical properties
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Finite element results for an AFM tip near a polyimide/SWNT composite sample. In (a), the computed electrostatic
force difference (F) and stiffness difference (k*) as a function of buried CNT bundle depth (radius = 20 nm, length
= 300 nm). The simulations for two tip radii are included for comparison. In (b), the FWHM calculated from the profile
across a CNT bundle as a function of CNT depth. A typical result, plotted in the inset, graphically illustrates the
higher lateral resolution produced by the CR-AFM technique
Computer-aided sub-surface
reconstruction and depth sensitivity