Nanobiotechnology manipulating molecules the scanning probe microscopy carbon fullerene carbon nanotubes building blocks for future nanotechnological application graphene the inorganic nanomaterial quantum dots

1. Manipulating molecules: The scanning probe
Microscopes
Nanotechnology is envisioned to make smaller and smaller
tools in order to manipulate atoms and molecules.
Scanning tunneling microscope (STM) and atomic force
microscope (AFM)
Both are different from conventional microscopy which is
based on construction of images by using beam of electron
or photons (in case of electron microscope).
STM & AFM microscopes are based on very fine scanning
of the sample surface using an ultrafine tip.

3. The image formed is based on the electrical tunneling
properties of the matter as in the case of STM or the
topographical properties of the sample as in the case of
AFM.
The generic name for such sort of microscopes is called as a
scanning probe microscope (SPM).
The tip or probe scans over the surface of the sample and
measures a tunneling current (in case of STM) or the
physical topography of the surface (in case of AFM).
Principally, the specifications of the scanning probe
machine allow us to reach a single atom resolution and
atomic organization of metallic substrates.

4. Carbon Fullerene: A new form of Carbon
Organic compounds are based on carbon as a key building
block.
1/5 of human body I is carbon, more than any element
except oxygen.
Biological entities like proteins and lipids are organic
compounds as well common industrial products such as
nylon, plastic etc
Synthetic abilities in organic chemistry in terms of
complexity and scale up process are enormous.

5. Carbon exists in three allotropic forms i.e amorphous,
graphite and diamond.
Diversity of carbon organization at molecular level shows
graphite is the softest substance and diamond is the hardest.
Molecular organization of the carbon can dramatically affect its
macroscopic properties.

6. Carbon Fullerene
Vaporization of graphite by using laser into new cluster
forms of carbon are called carbon fullerenes.
They are in the form of closed cage molecules in the
arrangement of hexagonal and pentagonal faces.
Common and stable cluster is buckministerfullerene.
It is a 60 carbon atoms spheroidal molecule like a bucky
ball.
C60 fullerene is the most abundant cluster of carbon atoms
found in carbon soot.
It is about 0.7 nm and has excellent electrical and heat
conductivity.

8. Applications of Carbon Fullerene
oServing as nanocontainers for drug delivery.
oCould serve as antiviral agents.
oModified C60 molecule can effectively inactivate HIV at
low micromolar concentrations.

9. Carbon nanotubes: Key building blocks for future
nanotechnological application
Elongated variants of the C60 fullerenes.
Resembles graphite sheets wrapped around into elongated
cylinders with or without capping at their ends.
Their length to width ratio is extremely high.
Can be formed in a single shell called as single walled
nanotubes (SWNTs)
Or in multiwall fashion known as multiwalled nanotubes
(MWNTs)
They have unique mechanical and electrical properties

10. Have ten time more tensile strength than steel.
Thus are suitable candidate materials for development of
ultra strong materials like in construction of car and
aviation industries.
Can be used as a source of fabrics and clothing for making
lightweight bulletproof fabrics.
Can be used in assembly of an ultra strong cable in
construction of space elevator.
Being very small and highly conductive carbon nanotubes
can be used as molecular wires, conductive composites and
interconnects.

11. Graphene
A single layer of carbon which is one atom thick is called
graphene.
It has high thermal and electrical conductivity and is
mechanically very strong yet strechable material.
Being transparent and very conductive it can be used in
liquid crystal displays and solar cells etc.

12. The inorganic nanomaterials
The noncarbon nanotubes made by inorganic material
which resemble like the carbon fullerene structures.
Tungsten, molebdenum etc can form 2D layer
rearrangements as evidenced in graphite structures for
making nanotube.
The structures that have formed in a cage fashion can be
rolled to form fullerene like structures. For instance the
nano particles of the layered WS2 compound can form
closed cage structures that are similar in their molecular
organization to carbon fullerenes.

13. Used in many industrial and technological applications.
as a solid lubricant
Increases the life span and efficiency of motors and other
power tools with motor parts
Used as additives for motor oil.
Used as lubricants of medical and dental devices.

14. Quantum Dots
The nano objects consist of semiconductor materials
surrounded by a shell composed of ZnS or CdS.
Also called as nanocrystals and have dimensions of few nm
to a few tens of nanometers.
Serve as a cage for electrons and the molecular diameters of
these structures reflect the number of electrons they contain.
The size may depends from a single electron to a collection
of several thousands.

15. Quantum dot behave like a giant atom.
Energy levels in a given quantum dot become quantized due to
confinement of electrons.
The band gap b/w the two energetic states determines the energy
of a photon that is being emitted by the transition b/w the two
states
The energy can be either in the visible or the infrared region
depending on the specific band gap