STS (Module 11)

• Nanotechnology

  -a group of emerging technologies in which the structure of matter is controlled at the nanoscale to produce novel materials and devices that have useful and unique properties (US Foresight Institute)

  -atomically precise technology (APT)

  -technology with the dimensions of less than 100nm
• What is a Nanoscale?


  A scale of measurement that uses nanometers or microns as units of measure
• Nanometer

  -one billionth of a meter or 10^9
• The central idea of nanotechnology is to employ individual atoms and molecules to construct functional structures.
• Nanoscience 

  -refers to the study, manipulation and engineering of matter, particles and structures on the nanometer scale (one millionth of a millimeter, the scale of atoms and molecules).
• Nanotechnology 

  -is the application of nanoscience leading to the use of new nanomaterials and nanosize components in useful products. 
• Lycurgus Cup (4th century AD) in the British Museum contains nanoparticles of silver and gold
• Richard Feynman

  -introduced the concept of nanotechnology

  -Lecture “There’s Plenty of Room at the Bottom” (1959)

  -Invention of the scanning tunneling microscope in 1981, atomic force microscope (1986) and the discovery of fullerene (C60) in 1985 led to the emergence of nanotechnology
• A scanning tunneling microscope is an instrument for imaging surfaces at the atomic level.
• Norio Taniguchi

  –first used nanotechnology term (1974)
• Eric Drexler

  –utilizes the molecular nanotechnology concepts at MIT (1986)
• Naturally Occuring

  -Forest Fires

  -Sea Spray

  -Mineral Composites

  -Volcanic Ash

  -Viruses
• Human Origin (Incidental)

  -Cooling Smoke

  -Diesel Exhaust

  -Welding Fumes

  -Industrial Effluents

  -Sandblasting
• Human Origin (Engineered)

  -Metals

  -Quantum Dots

  -Buckyballs/Nanotubes

  -Sunscreen Pigments

  -Nano capsules
• Nanomaterial properties

  -can be ‘tuned’ by varying the size of the particle (e.g. changing the fluorescence color so a particle can be identified)
• Types of Nano Materials

  -Carbon Based

  -Metal-Based

  -Dendrimers

  -Nanocomposites
• Carbon based nanomaterials (fullerenes, nanotubes, graphene)
• Metal-based nanomaterials (quantum dots, nanogold, nanosilver, metal oxides such as titanium dioxides)
• Dendrimers – these are nanosized polymers built from branched units
• Nanocomposites – composite materials made up of nanoparticles put together molecule by molecule. They are added to products to enhance mechanical, thermal, and flame-retardant properties.
• Applications of Nanotechnology

  -Environment

  -Agriculture

  -Medicine and Health

  -Engineering

  -Computer Science

  -Commercial
• In the medical field, dendrimers are used in drug delivery techniques
• Gold nanoparticles can be used to detect early stages Alzheimer’s disease
• In first aid, a bandage that is waterproof, elastic, and able to dissolve in the skin over time was developed by the MIT team led by Karp and Langer.
• Nanofilms can be used in thin films to make them water-repellant, anti-reflective, ultraviolet, infrared and scratch-resistant. They are used in the production of eyeglasses, computer monitors, and cameras to protect their surfaces
• In reducing environmental pollution, nanoscale materials that contain iron are used to remedy groundwater sites and other areas with hazardous wastes
• Incorporation of nanoparticles in packaging can increase the barrier to oxygen and slow down degradation of food during storage.
• Sunscreen lotion contains nanoparticles of zinc oxide and titanium oxide doesn’t leave a whitish tinge when rubbed into the skin.
• Nanorobots can be used as drug delivery and drug therapies to treat cancer tumor.
• The silicon transistors in computer may be replaced by transistors based on carbon nanotubes.
• Nanosensors are developed to detect salmonella, pesticides, and other contaminants on food before packaging and distribution.
• Fullerene is used as an ingredient in whitening cream that enhances skin absorption and helps fight the appearance of fine lines, wrinkles, sagging skin
• An animal study from the United Kingdom found that certain carbon nanotubes can cause the same kind of lung damage as asbestos.
• A coalition of consumer groups petitioned the U.S. Environmental Protection Agency to ban the sale of products that contain germ-killing nano-silver particles, from stuffed animals to clothing, arguing that the silver could harm human health, poison aquatic life, and contribute to the rise of antibiotic resistance.
• Researchers in Singapore reported that nano-silver caused severe developmental problems in zebrafish embryos — bolstering worries about what happens when those antimicrobial products, like soap and clothing, leak silver into the waste stream.
• The U.S. Department of Defense, in an internal memo, acknowledged that nanomaterials may “present”¦ risks that are different than those for comparable material at a larger scale.” That’s an overarching risk with nanomaterials: Their tiny size and high surface area make them more chemically reactive and cause them to behave in unpredictable ways. So, a substance that’s safe at a normal size can become toxic at the nanoscale.
• Australian farmers proposed new standards that would exclude nanotechnology from organic products.
• Nanomaterials are so small that they travel easily, both in the body and in the environment. Their tiny size and high surface area give them unusual characteristics: insoluble materials become soluble; nonconductive ones start conducting electricity; harmless substances can become toxic.
• Nanoparticles

  -are easily inhaled. They can pass from the lungs into the bloodstream and other organs. They can even slip through the olfactory nerve into the brain, evading the protective blood-brain barrier.
• Gold and Silver nanoparticles can be used to produce stained glass windows.