NANOTECHNOLOGY AND APPLICATIONS

By Loh Zheng Yi 3I316

What are the pictures about?

Watch the Video…

http://www.youtube.com/watch?v=g3QLLc-q07Q

This video depicts many uses of nanotechnology in electronics and medicine. It also shows a brief overview of the history of nanogold

What is nanotechnology?

Study and application of control of matter on an atomic scale (10^-9)

Applications of nanotechnology Medicine Nanomaterials Molecular Self Assembly Nanoelectronics

Nanomaterials

Characteristics Vastly increased surface area to volume

ratio Altered electronic properties

Uniformity in packing of molecules/atoms

Types Fullerenes Nanotubes Nanoparticles

Nanomaterials

Did you know? In the nanoworld, Copper becomes transparent Aluminum becomes combustible Gold can be used as a catalyst Silicon becomes a conductor Ferroelectric materials are able to switch

their magnetization energy (That means you can’t made a memory chip in

the nanoscale using conventional methods!) Zinc Oxide can block UV light efficiently

(currently used in sunscreen)

Fullerenes

A molecule that is fully composed of carbon

First fullerene to be discovered – C60 fullerene

Various types Buckyballs Nanotubes Megatubes Polymers

Buckyballs

Spherical carbon allotropes

Can also be made with elements such as Boron and Silicon

Applications Can act as aromatics Can act as

superconductors under specific conditions

Nanotubes

Watch the video on the synthesis of carbon nanotubes and their applications http://www.youtube.com/watch?v=ikYhyjPjKBs

Nanotubes Allotropes of carbon such that they resemble a

tube Characteristics

Length to diameter ratios of up to 132 000 000: 1 Extreme strength Efficient thermal conductors along the tube (up to 10

times as much as metals) but insulators perpendicular to the tube length

Electrical conductors Length of up to 18.5cm More than 80times the tensile strength of stainless steel Experiments have created nanotubes harder than

diamond

Applications of nanotubes

Nanomotor Using nanotubes encased

within another nanotube Nanoelectrical systems

A sheet of nanotubes can act as loudspeakers that amplify sound through thermoacousticity

Nanotubes can be used for flexible displays and touchscreens

Application of nanotubes

Solar cells Uses carbon nanotube complexes of

buckyballs and nanotubes Buckyballs can trap electrons when

excited with light energy Nanotubes can then act as wires to

transmit the electrons

Nanoparticles

Small clusters of molecules/atoms that behave as a whole unit

Uniform packing Consists of colloids

Solid particles small enough to exhibit brownian motion

Nanoparticles

History (Yes, this seemingly modern science does have a history) In the Middle ages and the Renaissance

(14th to 17th century), people found a way to make pottery glister

This is done by the glazing of a metallic film of silver and copper nanoparticles onto the clay

Addition of copper and silver salts to

vinegar

The heat (600°C) caused copper and

silver ions to migrate to the surface

A reducing agent would then turn those ions into

nanoparticles of silver and copper

metals

Colloidal Gold Also known as Nanogold Suspension of gold nanoparticles in a fluid Formed by the reduction of chloroauric acid Properties

Colour ranges from yellow to red depending on size of particles Due to the ability of gold nanoparticles to confine

electrons and produce quantum effects Colloidal gold melts near 300°C unlike bulk gold

(1064°C) Gold is now a semiconductor Gold is no longer inert

Application of Nanogold

Technological Purposes Synthesis of extremely fine wires Synthesis of semi conductors for computers Synthesis of touch sensitive screens and advanced

data storage Synthesis of efficient chemical catalysts

Nanogold can catalyze the conversion of Carbon Monoxide into Carbon Dioxide with 100% efficiency

Nanogold can be used to make firefighting masks that protect against CO poisoning for several hours

Nanogold can purify water and detect contamination

Application of Nanogold

Medicinal purposes Gold Nanoparticles can be attached to

antibodies to be used as a beacon which can then be detected by equipment (e.g. dark field imaging) to identify cancer cells

The presence of nanogold in cancer cells also make the cells vulnerable to light energy that would cause nanogold to heat up the cell until it dies

The use of gold nanorods, coupled with IR laser light, can be used to detect tumors deep within the skin

Nanomedicine

The utilization of nanotechnology to help overcome current medicinal technology limits

Applications include Advanced drug delivery methods New therapies Neuroelectronic interfaces and

nanoelectronic based sensors Cell repair machinese?

Drug Delivery

Focuses on maximizing the effect of drugs (so that they do not end up in non useful place)

Nanoparticles can be taken up by cells (unlike bulk materials) because of their size This can cause drugs to be distributed to

the desired cells via complex delivery mechanisms

This can also eliminate problems such as death of normal cells caused by poor biodistribution

Nanoparticles as seekers

Several functional groups can be attached to a nanoparticle

As tumors lack an effective drainage system, nanoparticles can accumulate easily at such cites.

Some nanoparticles such as cadmium selenide glow when exposed to UV rays, thus revealing the cancer cells.

Neuroelectronic Interface

Synthesis of a molecular structure that will allow the neural impulses to be detected

Through nanotechnology, computers may be able to be used to control the neural network and treat diseases that affects the neural network

Many limitations due to possible malfunctions and electrical disruption

Nanoparticles as seekers

References

Lehigh University (2004, April 29). Nanogold Does Not Glitter, But Its Future Looks Bright. ScienceDaily. Retrieved August 21, 2010, from http://www.sciencedaily.com /releases/2004/04/040428062059.htm

Chang Qing, Sun (2008, June 27). Nanogold chemistry. SciTopics. Retrieved August 21, 2010, from http://www.scitopics.com/Nanogold_chemistry.html

http://www.mi2g.com/cgi/mi2g/frameset.php?pageid=http%3A//www.mi2g.com/cgi/mi2g/press/110210.php

http://www.nanowerk.com/news/newsid=15631.php http://en.wikipedia.org/wiki/Nanomedicine http://en.wikipedia.org/wiki/Carbon_nanotube http://en.wikipedia.org/wiki/Nanogold http://en.wikipedia.org/wiki/Fullerene http://en.wikipedia.org/wiki/Nanomaterials http://en.wikipedia.org/wiki/Nanoparticle