In measurements, we take nano as ^-9

Definition : The world at a microscopic level, as dealt with by nanotechnology

Definition : The engineering of functional systems at the molecular scale

With 15/342 atoms, this parallel-shaft speed reducer gear is one of the largest nanomechanical devices every modeled in atomic detail.

Definition : A particle having one or more dimensions of the order of 100nm or less

A bulk material should have constant physical properties regardless of its size, but at the nano-scale size-dependent properties are observed (eg. yellow gold, gray silicon)

Pure gold has a bright yellow colour Maintains without oxidizing in air or

water Physical properties :

› Dense› Soft› Shiny (Not for nanoparticles)› Most malleable and ductile pure metal

known

Measured in nanometers as the gold particles contains only tens, hundreds of atoms (Note:1nm = 1 billionth a metre!)

Gold itself does not always glitter If gold was created in tiny chunks, it

turns red, blue, yellow and other colours

10nm particles absorb green light, appearing red.

Properties change dramatically from its bulk form› Becomes a very good catalyst› No longer a metal, but a semiconductor› Melting temperature decreases dramatically› Ceases to be noble› Magnetic› Equilibrium structure changes to icosahedral

symmetry, or they are even hollow or planar

Properties of NanoGold might be reconciled by the recently developed bond-order-length-strength(BOLS) correlation mechanism which indicates that the broken bond induced local strain and quantum trapping and the associated densification of charge and energy in the surface skin are responsible for the size induced behaviour.

The shorter and stronger bonds in the surface skin not only lower the energy levels of the electrons but also enhance the electronegativity and hence make the less-coordinated atoms to gain electrons from the specimens, demonstrating the catalytic effect as observed

Definition : A field which takes a materials science-based approach to nanotechnology

Other kinds of nanomaterials include › Carbon Nanotubes› Fullerenes (Carbon-60)

First observed by Sumio Iijima in 1991 Extended tubes of rolled graphene sheets Few nanometers in diameter Important role in the context of

nanomaterials, due to its novel chemical and physical properties

Two Types : › Single-walled› Multi-walled

Remarkable Properties : › Mechanically very strong (as stiff as

diamond)› Flexible› Conduct electricity extremely well

Applications : › Reinforced composites› Sensors› Display devices

Discovered in the mid-1980s as a new class of carbon material

Spherical molecules about 1nm in diameter

Produced by resistively heating graphite rods in a helium atmosphere

Applications› Miniature “ball bearings” to lubricate

surfaces› Drug delivery vehicles› Electronic circuits

Fighting Cancer Containers Drugs

Scientists are using nanoparticles and lasers to kill cancer cells by blowing them up from the inside

So far, the treatment has been tested in a lab setting on leukemia cells and cells from head and neck cancers

Gold nanoparticles are placed inside the diseased cells and zapped with laser

The laser causes the particles to swell into “nanobubbles” that will burst the cells

Nanobubbles are created when gold nanoparticles are pelted by short pulses of laser

The bubbles can differ in size depending on the power of the laser

The larger they are, the more they can burst the cell they are in

Nanobubbles are also able to blast through plaque that builds up and blocks arteries, which causes atherosclerosis

A plastic container that uses silver nanoparticles to keep food, allows it to be fresher longer

Nanomaterials are being developed with enhanced mechanical and thermal properties to ensure better protection of foods from exterior mechanical, thermal, chemical or microbiological effects

Silver is naturally anti-germ, anti-mould and anti-fungus

This special containers decreased bacteria growth by 98 percent over a day due to the silver nanoparticles

“If the disease doesn’t kill, the cure will”

Many therapeutic drugs administered by pill, syringe cream can be a hit or miss delivery system

Only 1 out of 100,000 molecules of an intravenous drug make it to the intended spot in the body

Bioengineer Frank Alexis has suggested that a way to improve targetting a drug and preventing it from being passed out of the body is enveloping it, protecting it

Envelopes used are nanoparticles

Think of an M&M Nanoparticle – Outer candy shell Medicine – Chocolate The goal of the drug would be the

same as for an M&M : To melt in the right place

A handful of nanoparticle medicines have already been approved for use for treating diseases, particularly cancers

“Nanoparticles can be modified many ways. They can be coated so that they can be durable and stable. They can be patterned so that they match up like a key and lock to connect to certains cells, tissues and organs. Some drugs are not taken up because of their physical and chemical properties”

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nanomaterials.html http://news.techworld.com/green-it/3212389/cancer-fighting-technology-

uses-nanoparticles/?olo=rss http://www.foodproductiondaily.com/Packaging/Container-uses-

nanoparticles-to-extend-shelf-life http://www.physorg.com/news174219683.html