Nanotechnology

Prof. Andrea M. Armani

Overview

Definition of Nano

Intel Chip

Applications of Nanotechnology

Size and Scale: Factors of 1000

Courtesy of Charles Tahan

Size and Scale: Factors of 1000

Courtesy of Charles Tahan

Size and Scale: Factors of 1000

Courtesy of Charles Tahan

First Nanotechnology: Stained GlassGold (Au) and Silver (Ag) nanoparticles create colorsGold (Au) and Silver (Ag) nanoparticles create colors

Size: 25nm Size: 100nm

Size: 50nm Size: 40nm

Gol

d

SilverSize: 100nm Size: 100nm

The New York Times; Images courtesy of the Stained Glass Museum, Britain; Kenneth Chang, "Tiny Is Beautiful: Translating 'Nano' Into Practical", The New York Times, February 22, 2005.

Overview

Definition of Nano

Intel Chip

Applications of Nanotechnology

Who does nano?

El t i l

Mechanicalengineers

Ci il

One example:

Electricalengineers

Civilengineers

Chemicalengineers

AeronauticalEngineers/scientists

High performance polymer solar cell

MaterialsComputerEngineers/scientists

EnvironmentalEngineers/scientists

Engineers/scientists

Impact areas of Nanotechnology

• Energy• Solar cells• Batteries

• “Technology”• Computers• OLEDs• Photonics• Photonics

• Biotechnology• Imaging

Di ti• Diagnostics• Therapeutics (cancer, HIV)

• Consumer ProductsSki• Skin care

• Composites

Solar Energy

Nanowire based

Crystalline Silicon

Nanowire based

Polymer based

Nano-Silicon Solar Cells

Same amount of energy even when bent!- The solar cell doesn’t break!

Yoon, J. et al, Nat. Mat. 7 (2008).

Silicon solar microcells: with microlens

Yoon, J. et al, Nat. Mat. 7 (2008).

Silicon solar microcells: with microlens

- Lens array increases collection efficiency of solar cell if the sun is “on-axis”y y

Yoon, J. et al, Nat. Mat. 7 (2008).

Energy: Nanowire-based solar cellsOne problem with solar cells isOne problem with solar cells is getting all of the solar energy from the anode to the cathode efficiently.

The nanowires act as thousands of little electrical wires, providing conduction paths.conduction paths.

Panel made with nanowire technology

Quantum Dot/Nanowire Solar cells

Z O i lZnO nanowires grown on a glass substrate and decorated with CdSe quantum dots is the photoanode.

A second glass substrate, coated with a 100 Å layer of Pt, is the photocathode.

The space between the two electrodes isThe space between the two electrodes is filled with a liquid electrolyte (to encourage transfer), and the cell is illuminated from the bottom, as shown.

Leschkies, K. et al, Nano Lett. 7 (2007).

Impact areas of Nanotechnology

• Energy• Solar cells• Batteries

• Biotechnology• Imaging• Diagnostics• Therapeutics (cancer HIV)• Therapeutics (cancer, HIV)

• “Technology”• Computers

OLED• OLEDs• Photonics

• Consumer ProductsSki• Skin care

• Composites

BiotechnologyDrug Discovery Biomedical DevicesDrug Discovery•Solving structures of virus/bacteria to understand how to inhibit behavior•Developing new methods to block interactions between pathogen and host

Biomedical Devices•Curing degenerative diseases•Repairing traumatic injuries•Minimally invasive surgary

interactions between pathogen and host

Imaging Diagnostics

Au nanoparticle HIV treatment Neural Implant

Imaging•Developing new imaging modalities (equipment)•Developing new enabling tools (new fluorescent molecules lasers etc )

Diagnostics•Developing new diagnostic methods•Developing new tools (devices or platforms)

fluorescent molecules, lasers, etc.)

Quantum dot imaging Nano-cantilever sensor

El t i l M h i l

Sensing Methods

Electrical Mechanical

In2O3nanowire

Si/SiO2back gate

Ti/Au electrodes

example: Nanowire/Nanotube based detection example: Cantilever based detectionexample: Nanowire/Nanotube-based detection

University BaselZhou, USC

example: Cantilever-based detection

OpticalMagnetic

example: Fluorescent-probe assayY

Y

Y

example: Magnetic nanoparticles

G. MacBeath, Nat. Gen. 32 2002.

Chemical Sensing

Operation principle: NO2 molecules withdraw electrons from In2O3

ON

In2O3nanowire

Ti/A

Si/SiO2 back gate

Ti/Au electrodes

Advantage of In2O3 nanowires:

In

Advantage of In2O3 nanowires:1. Single crystal; 2. No amorphous coating (as compared to

Si NWs with amorphous SiO2);3 Hi h f t l ti3. High surface-to-volume ratio.

A: exposed to NO2 in airA: exposed to NO2 in airB: UV light illumination to recover the deviceC: turn off UV;

C. Zhou: EE/MASC

Detection of PSA

PSA is a bio marker for the presence of prostate cancer, which is the most frequently diagnosed

cancer among men in the UScancer among men in the US.

Standard PSA Probability of cancer

0-2 ng/mL 1%

2 4 / L 15%2-4 ng/mL 15%

4-10 ng/mL 25%

>10 ng/mL >50%

Collaboration with Richard Cote, USC Center for Cancer Research

Selective detection of PSA in PBS

Individual In2O3 Nanowire:Enhanced Conduction

Nanotube Mat:Reduction Conduction

1. No response when BSA was added2. Detection of PSA down to 5ng/mL achieved in Phosphate Buffered Solution (PBS) buffer2. Detection of PSA down to 5ng/mL achieved in Phosphate Buffered Solution (PBS) buffer

Real-time detection of PSA in aqueous environment

J. Am. Chem. Soc.; 2005; 127(36); 12484

Optical sensing technologyHigh Concentration Single MoleculeHigh Concentration Single Molecule

• Fluorescent Arrays (ex. ELISA)• Microscopy (confocal, wide field)

Imaging• Total Internal R fl tiReflection Fluorescencemicroscopy (TIRF)• Nanoscopyab

eled

py

Probes• Optical Tweezers

D Lidk t l N t Bi t h 22 2 (2004) T Ch l N l A id R 34 17 (2006)

L

D. Lidke, et al, Nat. Biotech. 22 2 (2004). T. Chan, et al, Nucl. Acids Res. 34 17 (2006).

• Resonant/Evanescent microcavity

ee

• Optical waveguides• Surface plasmon resonance

R t it

abel

-fre • Resonant cavity

A. Armani, et al, Science (2007).

La

Y. Fainman, UCSD

Optical Sensor Fabrication

Silica toroid

Silicon pillar

(a)

SEM of microtoroid resonator85m

(a) (b) (c) (d)

D. Armani et al, Nature 421 (2003).Q~106 Q~10850m

Armani Lab Research

O ti l Ch D t t bl Si lOptical Change:• Refractive index change• Diameter change

Detectable Signal:• Q change• Resonant frequency change

ansm

issi

on

• Material loss change • Transmission change

Previous detection demonstrationsMolecules Cells

Tra

Wavelength ()

sion

sion

Wavelength Change

- Molecules - Cells- Chemicals - Virus- Protein conformations Tr

ansm

iss

Tran

smis

s

Transmission Change Q ChangeWavelength () Wavelength ()

A. M. Armani, et al, Science (2007).

Armani Lab: Sensors need to be specific

Click Chemistry www.bioteach.ubc.ca

HN

NH

Oprobe

Click Chemistry b oteac ubc ca

Lipid bilayers

SiO2

O O OH

Si OMe

C

O

O

NOH

N h d i i id (NHS) t h i tN-hydroxysuccinimide (NHS) ester chemistry

H. K. Hunt, et al, Sensors, under review (2010). L. M. Freeman, et al, Nano Letters, under review (2010).

Quantum Dots changed world of taking images of cells in the early 1990’s

Imaging: Cadmium Selenide QDot’sQuantum Dots changed world of taking images of cells in the early 1990 s.

Imaging: Cell Structure Review

M

Imaging: QDots

Mouse• Microtubules (green, Qdot 525-streptavidin)• Mitochondria (red, Qdot 605-streptavidin)• Nuclei (Hoechst blue dye - a dye that is preferentially absorbed by the nucleus).Nuclei (Hoechst blue dye a dye that is preferentially absorbed by the nucleus).

Imaging: Half-life of QDot

H lf lif ti til d /fl t l l i l itti li htHalf-life~time until a dye/fluorescent molecule is no longer emitting lightlonger half-life = better fluorescent molecule (for most applications)

Nuclear antigens stained with Alexa Fluor 488 (green dye)Microtubules stained with Qdot 605 streptavidin conjugate (red QDot).Microtubules stained with Qdot 605 streptavidin conjugate (red QDot).

The time series shows emission after an initial illumination.

QD t h h l h lf lif !QDots have much longer half-life!

“Lighting Up Cells with Quantum Dots,” Biotechniques, 34(2), 296 (2003).

Skin as delivery target

Skin•Skin represent the largest and most easily accessible organ of the body•Low permeability to most moleculesLow permeability to most molecules•Outer layer (approximately 20 microns thick) is the contributor to impermeability

ff fDrug related properties that affect flux•Concentration gradient of drugs within the skin

•Ability of drugs to partition into the skinAbility of drugs to partition into the skin•Ability of drugs to partition out of the skin into the underlying tissues

•DiffusivityD t i d b h i l t t f th•Determined by chemical structure of the

drug

http://www.clinimed.co.uk/Portals/10/images/Derm_Figure1.jpg

Transdermal Patch with nano-needles

Delivery of drug/vaccine into skinExample of transdermal patch(polymer needles)

Images: Courtesy Nanotechnology Victoria Ltd, Resin Design

Benefits Of Transdermal Patches•Transdermal patches can deliver nano formulated drugs/vaccines which

Benefits of Transdermal PatchesBenefits Of Transdermal Patches•Transdermal patches can deliver nano-formulated drugs/vaccines, which

• have unique properties• can easily enter blood vessels once delivered to skin• can target particular cell types, such as immune cells

•Examples of drugs that could be patch-delivered: • proteins such as insulin

•Examples of vaccines that could be patch delivered:• protein vaccines• protein vaccines• DNA vaccines.

•Due to directed delivery of nano-formulated drugs/vaccines, the use of patches means that

• only small quantities of drugs/vaccines are required• less drug/vaccine is ‘wasted’

i.e. dispersed in blood or connective tissue before it reaches target cellsp g• less side effects due to small dosage delivered directly to target cells • an optimal immune response is generated.

Benefits of Transdermal Patches

Protrusions can be specifically engineered to ensure:D li di tl t i• Delivery directly to immune cells therefore less material required

• Painless application and noPainless application and no scar tissue formation

• Versatility in applications: vaccines, drugs, hormones, wound healing proteins.

Image: Courtesy Nanotechnology Victoria Ltd

Microscopic images of transdermal patch protrusions

Out-of-plane Micro-needle

f fThere is still some debate about if it is better to focus on using nano- to improve transfer across skin (ie poke small holes) or if the development of nano-syringes should be focusfocus

Proceedings of IEEE, 92:1, (2004).

Capsule Endoscopy aka PillCam

• Swallowable system: 11mmx30mm

• Include video camera, light source and itransmitter

• 50,000 images transferred during 8hr test

• Recoverable

• Passes through system “naturally”

Esophagus Images with PillCam

Normal Possible Barrett’s* in esophagusNormal Possible Barrett s in esophagus

PillCam images:

Barrett’sClassic Endoscopy images

Barrett s

http://www.amc.edu/http://singluten.files.wordpress.com

*Barrett’s: change in cellular lining of the lower esophagus; related to gastrointestinal reflux; can result in a peptic ulcer

VeriChip

OOnly FDA-approved human-implantable RFID microchip

Security (and other tracking methods) hasSecurity (and other tracking methods) has reached the subcutaneous level for Mexico’s attorney general and at least 160 people in his office (as of March 2007).

They have been implanted with microchips that get them access to secure areas of their headquarters.q

The chips are made by VeriChip.

IEEE Spectrum, March 2007.

Impact areas of Nanotechnology

• Energy• Solar cells• Batteries

• Biotechnology• Imaging• Diagnostics• Therapeutics (cancer HIV)• Therapeutics (cancer, HIV)

• “Technology”• Computers

OLED• OLEDs• Photonics

• Consumer ProductsSki• Skin care

• Composites

Technology

Photonics(Nanowire laser)

Computers (Intel Chip)

Nano-lithography(dip-penlithography)

Micro/Nano-machines(Microgears imaged with a spider mite)

Technology: Armani Group Research

Waveguide

500nm

Resonant Cavity

500m500m

H. Hsu, C. Cai and A. M. Armani Opt. Express 17 25 (2009).; H. S. Choi.,et al Opt. Lett. 35 4 (2010).X. Zhang, et al, Appl Phys Lett 96, 153304 (2010).

Technology: OLED

OLED O i Li ht E itti Di dOLED: Organic Light Emitting Diode

Nobel Prize in Chemistry (2000) for conducting polymers:for conducting polymers:• Heeger (UCSB)• MacDiarmid (U Penn)• Shirakawa (U Tsukuba)

Technology: OLED

Samsung’s Bendable OLED display

Research Group MembersP t d /G d t St d tPost-docs/Graduate Students

Undergrad Students Fields:BiologyBiomedical EngineeringChemistryChemical Engineering

Funding:

Chemical EngineeringElectrical EngineeringMaterials Science