Nanotechnology

• Nanotechnology is the understanding and control of materials on the

molecular, atomic, or even subatomic scale.
• A nanometer is an extremely small unit of length—a billionth (10^-9) of
a meter.
• Deals with dimensions between approximately 1 and 100 nanometers.
• Highly interdisciplinary field
Origin of Nanotechnology
• The concept of nanotechnology was given
by Richard Feynman in his talk “There’s
plenty of room at the bottom”.
• The term ‘nanotechnology’ was coined by
Professor Norio Taniguchi
• 1981: Invention of scanning tunneling
microscope made it possible to see
individual atoms
• 1982: Invention of atomic force
microscope
 Origin of Nanotechnology
Scanning tunneling microscope Atomic force microscope
A scanning tunneling Atomic Force Microscopy (AFM) is a high-
resolution imaging technique that is used to
microscope (STM) is a type study the surface morphology and
of microscope used for high resolution properties of a wide range of materials(e.g.,
imaging surfaces at the atomic level polymers, ceramics, glass, biological
without the use of light or electron materials etc) at the nanoscale.
beams. Developed in 1986, AFM has become a
powerful tool in various scientific
disciplines, including physics, chemistry,
biology, and materials science.
The invention and development of STM
and AFM made it possible for
nanotechnology to become a reality.
Role of Nanotechnology in Medicine
• Nanotechnology can help to revolutionize the way we detect and treat a
disease.
• Wide ranging medical applications are present and research for new
applications is ongoing.
• e.g., research on nano-robots to make repairs at cellular level.
• Main applications in medicine:
• Drug delivery: using NPs to deliver drugs, heat, light or other substances to specific
kind of cells (like cancer cells).
• NPs are engineered to get attracted to diseased cells so healthy cells are not damaged.
• Recent research is going on to develop a method to deliver cardiac stem cells to damaged heart
tissue.
 Role of Nanotechnology in Medicine
• Diagnostic Techniques: • Antibacterial treatments:
• Example 1: early detection of cancer • Research on the use of gold NPs to kill
by using antibodies attached to pathogenic bacteria.
carbon nanotubes in chips to detect • Can be effectively used in sterilization of
cancer cells in bloodstream. hospital equipment
• Example 2: a test method for the
early detection of kidney damage is
being developed.
• Uses gold nano rods which go and stick
to proteins produced by diseased
kidney.
• Protein accumulation leads to color
change of nano rod= disease detected.
Role of Nanotechnology in Medicine
• Wound Treatment:
• In wound healing studies, novel
therapeutic approaches have been
proposed to deliver an
effective treatment. Nanoparticle-based
materials are preferred due to their
antibacterial activity, biocompatibility,
and increased mechanical strength
in wound healing.
• Example: Development of polymer NPs
that act as synthetic platelets and
significantly help in wound healing by
preventing blood loss
 Role of Nanotechnology in Food
• Nanotechnology can be used widely in the field of food, such as in
cultivation, processing, packaging, shelf life and bioavailability of
nutrients. Some examples are discussed below:
1. Food ingredients:
Development of nano-scale ingredients to improve food color, texture and flavour.

e.g., NPs of TiO2 and SiO2 are used as food additives and TiO2 is used as
coloring agent in sugar coating on doughnuts.
 Role of Nanotechnology in Food

2. Food Production and packaging: 3. Nutrient and Dietary Supplements:

• Nanomaterials used for food packaging • Nanomaterials are used as additives
have multiple benefits e.g., detection of
microbial contamination or increased
in health supplements (e.g., vitamins,
bioavailability of nutrients. antioxidants etc) as they increase
• Example: use of ZnO and MgO NPs in absorption efficiency by improving
food packaging; use of amorphous nutrient bioavailability.
silica used in food containers and
packaging
Role of Nanotechnology in Food
4. Food storage: 5. Food nano-sensors:
• Food preservation is possible • Nanomaterials are used sensors to
due to the antimicrobial detect microbial contamination
properties of nanomaterials and regulate food environment
• Nano sensors can help to • Sensors are installed in packaging
monitor storage conditions plants in food industries
Role of Nanotechnology in Food
6. Nano coatings:
• Nano coating films having uniform
layers of NPs .
• Ability to detect minor
contaminations
• Edible nano-coatings act as barrier
against environmental factors (e.g.,
moisture and gaseous exchange)
• Helps to maintain food color,
texture and flavor.
• Increases the shelf life of foods
Role of Nanotechnology in Computational
Systems
• Computational nanotechnology is a branch of nanotechnology
concerned with the study, design, operation, analysis and optimization
of nano-scale systems.
• The design of a nano-scale device has the following 4 phases:
• Prediction of material components having appropriate physical and chemical
properties
• Design and assembly of device
• Device is analyzed in simulated operational conditions
• Control and optimization
 Role of Nanotechnology in Computational
Systems
• Design efficient materials for solar • Building complex electronic
cells: circuits:
• Researchers have created a new • Carefully introducing structural
material that overcomes two of the defects in carbon nanotubes
major obstacles to solar power: (CNTs) can direct electrons along
1. it absorbs all the energy contained in specific pathways, providing a
sunlight, and better way to engineer complex
2. generates electrons in a way that electronic circuits.
makes them easier to capture.
 Role of Nanotechnology in Computational
Systems
• With the advancements in electron microscopy, researchers are able to
microscopically measure atomic displacements precisely to a few picometres.
A picometre corresponds to a billionth of a millimetre a distance that is one
hundred times smaller than the diameter of an atom.
• Beneficial in mapping electron states
Role of Nanotechnology in Computational
Systems
• Graphene, a one-atom-thick sheet of carbon, was discovered in 2004
and is considered a potential heir to copper and silicon as the
fundamental building blocks of nanoelectronics.
• Results of computational studies enabled us to learn that when
deposited on a surface treated with oxygen, graphene exhibits
semiconductor properties. When deposited on a material treated with
hydrogen, however, graphene exhibits metallic properties.
 Role of Nanotechnology in Energy
Nanotechnology is being used in the energy sector to improve the
efficiency of current systems as well as develop new energy generation
methods. Some applications include:
• Nanotube filled epoxy can be used to produce strong and light weight
blades in windmill – increases energy generation.
• Solar steam device: sunlight concentrated on NPs can produce steam with
high efficiency. Solar steam device may help developing countries in:
• Water purification
• Disinfecting dental instruments
 Role of Nanotechnology in Energy
• Producing high efficiency light bulbs: • Generating electricity from waste heat:
• A nano-engineered polymer matrix is • Sheets of nanotubes to build thermo cells
used in produce high efficiency light bulbs • When one side of the material is hot the
• Shatterproof other is cold causing an electric charge to
• Two times more efficient build up along the temperature gradient.
• An idea in development is to update • If these nanotube sheets are wrapped
incandescent light bulbs by surrounding around hot pipes (e.g., car exhaust pipes)
them with crystalline material that heat emitted from the car can be converted
converts waste IR → Visible light into electricity
 Role of Nanotechnology in Energy
• Nanofibres can be moven into • Nanotech solar cells can be
clothing, these are capable of turning manufactured at much lower cost than
motion into electrical energy, which normal solar cells.
one can use to power their electronic • Nanotechnology is being used to and
devices. reduce their costs. improve efficiency
• Nanomaterials are being used to make of fuel cells
batteries which can remain efficient for • Power losses can be reduced by using
decades and can charge at a much wires containing carbon nanotubes
faster rate. which have much lower resistance.
Exobiology
What is Exobiology?
• Exobiologists study how life may have originated here on Earth and
where it may also exist in the universe.
What Is Life?
• The basic units of life are cells.
All living organisms are either single-celled or multicellular.
Cells are bounded by membranes and contain DNA and RNA.
• DNA contains the genetic code.
• RNA translates the genetic code into proteins.
• Living organisms reproduce either individually or in pairs.
• Living cells carry out complex chemical reactions to convert materials
and energy for their own use (metabolism).
Types of Cells
• Prokaryotic cells contain no nucleus.
• Bacteria are prokaryotic cells.
• First organisms to show up in the fossil record are prokaryotes.
• Eukaryotic cells.
• More complicated structure then prokaryotic cells.
significance of water
• Water is essential to the chemistry of all biological systems.
• It is the medium in which biochemical reactions take place in.
• In looking for signs of life either here on Earth or elsewhere scientists
look for signs of liquid water.
Biomolecules
• Biomolecules are Organic Compounds Biomolecules are large
molecules with a carbon skeleton.
• Organic compounds are those molecules that contain carbon.
• All life as we know it is based on carbon compounds. Did organic
compounds arrive on earth via comets?
Miller-Urey Experiment
• Origin of the Molecules of Life Miller-Urey Experiment.
• Early atmosphere was believed to contain methane, ammonia, water
and hydrogen.
• Miller created such an "atmosphere."
• It consisted of methane, ammonia, water and hydrogen above an
"ocean" of water. T
• hen he subjected the gases to "lightning" in the form of a continuous
electrical discharge.
• After a few days, he analyzed the contents of the mock ocean.
• He found a mixture of organic compounds and amino acids in the
artificial ocean.
Where Did Life Originate on Earth?
• Deep Sea Thermal Vents?
• First discovered in 1979.
• Scientists discovered whole ecosystems of organisms living in the
absence of sunlight.
Panspermia
• A theory developed by Svente Arrhenius.
• The theory states that life did not originate on the Earth, but
originated elsewhere in the universe.
The Search For Life Outside Earth The Planet Mars
• The Viking missions found no evidence of organic compounds in the
Martian soil.
• ALH84001.
• A meteorite found in Antarctica and determined to have originated
from Mars.
• Along tiny cracks scientists discovered signs of what appears to be
fossilized bacteria.
ALH84001
• 1. The meteorite is definitely of Martian origin.
• 2. The presence of complex organic molecules.
• 3. The presence of bacterial metabolites.
Is There Life Elsewhere in The Solar System?
• NASA is currently looking at three other possibilities; Mars, Europa
and Titan.
Jupiter’s moon Europa
• Evidence from images taken by Galileo show regions resembling ice
flows on Earth.
• The heat generated by tidal forces due to interactions with Jupiter’s
gravity field may be enough to liquefy some portion of Europa’s icy
crust.
• Could Europa support microbial life?
Saturn’s moon Titan
• Laboratory simulations show that a Titan-like atmosphere, primarily a
N2 /CH 4 mixture, under various energetic excitations will form
complex organic molecules and adenine, a component of DNA.
conclusion
• Bacteria can resist adverse conditions by forming spores.
• Bacteria can live under an enormous wide range of conditions most
of which would kill eukaryotic organisms.
• The main thing that bacteria need to survive is liquid water.
• If there is other life in our solar system it is most likely bacterial?