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Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

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Page 1: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present
Page 2: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Overview• Towards precise patterning of nanoparticles for

nanoelectronic and plasmonic devices• DNA used to from complex nanostructures

• Authors present method of fabricating nanoparticle arrays with controlled periodicity with 3-D DNA nanotubes

-Rothemund, P. W. K. Nature 440, 297-302 (16 March 2006)

Page 3: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Design

• One long DNA strand (black) with 170 short ‘staple’ strands (red)

• (A), (B), (C) are clustered biotin

• DNA forms 6-helix nanotube bundle (412 x 6 nm)

Page 4: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Assembly & Binding

• Height = 1.7- 3.5 nm (6 nm)

• Length = 436 +/- 14 nm (412 nm)

Page 5: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Assembly & Binding

• Successful attachment of 9 streptavidin (height increase ~0.5 nm)

• Periodicity of 45 nm (43 nm expected)

Page 6: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Assembly & Binding

• QDs have similiar spacing

• 5.5 nm height cross section

• 49 nm periodicity

Page 7: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Spatial Control

Page 8: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Conclusion

• Powerful and convenient pathway to control nanoparticle patterning

• Self-assembling scaffold for nanoscale electronic and photonic devices

• Variations available for spacing, length, QD size, and QD material

Page 9: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present
Page 10: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Controlled Drug Deliver

• Self-assembled micelles– Biocompatible and biodegradable– Amphiphilic block copolymers (PEG, PCL,

PLA)

• Inefficient drug release

Page 11: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

PEG Alternative

• Dextran (Dex)– Aqueous soluble, biocompatible, branching– -OH functionality for conjugation

• Authors report shell-sheddable biodegradable Dex-SS-PCL micelles for drug delivery

Page 12: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Reduction-Responsive Delivery

Page 13: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Synthesis

Page 14: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Micelle Formation

• Average micelle size increased from 60 to 200 nm with DTT addition– Aggregates from lose of

solubilizing shell

• Little change after 24hrs w/o DTT

Page 15: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

DOX Release

Page 16: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Cellular Uptake

2 hr

4 hr

24 hr

Page 17: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Cellular Uptake

2 hr

4 hr

24 hr

Free DOX

No DOX

Page 18: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Toxicity

• Free DOX and cleavable micelle show similar response

• Control and non-DOX loaded micelle show similar response

Page 19: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Conclusion

• Nontoxic Dex-SS-PCL diblock copolymers with high drug loading efficiency were developed

• Micelles are stable and allow for rapid drug release in response to intracellular levels of reducing potential

Page 20: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present
Page 21: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Overview

• Effort to mix nanoparticles (NP) with polymers to combine unique physical properties with processibility

• Need efficient ways to control NP arrangement in polymer matrix– Dispersion of NP impacts electronic,

transport, and mechanical properties

Page 22: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

NP Incorporation

Page 23: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Phase Dispersion

Page 24: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Conclusions

• Initially NPs are randomly incorporated in swollen polymers

• Polymers pack more densely with water and NPs phase segregate to polymer core-shell interface

Page 25: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Nano Lett., Article ASAPPublication Date (Web): January 26, 2010

Page 26: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Goals

• Efficient, highly portable energy sources for hand-held electronics

• Decreasing power requirements– Augment batteries with ‘scavenger’ systems– Salvage otherwise wasted energy

Page 27: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Wasted Energy…

• Work by the human body– Breathing

• Lung expansion/contraction generate ~1 W (charge pacemakers?)

– Walking• A heel strike during walking has 67 W of power

available (~1-5% energy to power cell phones)

Page 28: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Piezoelectrics

• Crystals become electrically polarized by mechanical stress (and vice versa)

• Processing - high temperature, rigid inorganic substrates• Authors present approach to incorporate crystalline

piezoelectric lead zirconate titanate (PZT) onto rubber substrates for flexible energy conversion

-http://www.piezomaterials.com/

Page 29: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Production

Processed into nanothick ribbons and printed onto polydimethyl-siloxane (PDMS) stamps via dry transfer

Page 30: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Function(a) Schematic of a specimen indicating

piezoelectric bending and measurement.

(b) Oscillating pressure (left axis) and induced dielectric displacement (right axis)

Page 31: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Characterization

Page 32: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Summary

• Highly crystalline piezoelectric ceramic ribbons have been transferred onto flexible rubber substrates

• Efficient electromechanical energy converters towards wearable/implantable energy harvesters

• Challenges to overcome: stretchable substrates, cycling longevity, storage/power conversion on substrates…

Page 33: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present
Page 34: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Light Concentration

• Surface plasmons– Electromagnetic surface waves carried by

density fluctuations of electrons

• Patterned metals– Films, trenches, gaps, tips for control and

delivery of surface plasmons

Page 35: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Surface Plasmons

• Focusing on tip or apex allows for excitation of highly local and extremely intense optical fields– ‘Optical lightning rod’

• Authors present three-dimensional plasmonic nanofocusing with patterned gold and silver pyramids

Page 36: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Nanopyramids

500 nm

500 nm

200 nm

1000 nm

Light incident from above is backscattered into plasmons that travel up sides and corners, converging at the apex

Page 37: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Fabrication

-Xu, Q., Tonks, I., Fuerstman, M., Love, C., Whitesides, G. Nano Lett., 2004, 4 (12), 2509.- Henzie, J., Kwak, E., Odom, T. Nano Lett, 2005, 5 (7), 1199.

Page 38: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Fabrication

-Xu, Q., Tonks, I., Fuerstman, M., Love, C., Whitesides, G. Nano Lett., 2004, 4 (12), 2509.- Henzie, J., Kwak, E., Odom, T. Nano Lett, 2005, 5 (7), 1199.

Page 39: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Simulations

Page 40: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Simulations

Page 41: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Imaging

Page 42: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Pyramids in Action

Page 43: Overview Towards precise patterning of nanoparticles for nanoelectronic and plasmonic devices DNA used to from complex nanostructures Authors present

Conclusion

• 3-D nanofocusing with well-defined plasmonic hot spots

• Applications in scanning-probe microscopy, optical trapping, high-density data storage

• Thin films allow for backside excitation