Author: Ashok B Sharma
Publication: The Financial Express
Date: January 21, 2008
URL: http://www.financialexpress.com/news/Nanotech-evolved-over-billions-of-years/263815/0
Nanotechnology might have become the buzzword
today but few are aware that it was in use in ancient times for producing
a number of products. Of late, scientists have not only rediscovered it, they
have also reinvented it to keep in pace with changing times, claims American
chemist and Nobel Laureate, Robert Floyd Curl Jr of Rice University. Curl
is known for his contributions to microwave and laser spectroscopy and the
discovery of the first fullerene-the third known form of pure carbon (after
diamond and graphite) in 1985. Curl's initial work was on small clusters of
atoms of semiconductors, such as germanium and silicon. For his contributions,
Curl shared the 1996 Nobel Prize for chemistry with Smalley and Harold Kroto.
Later work on the discovery by other scientists developed fullerene chemistry,
devoted to the use of fullerenes in the production of superconductors, industrial
catalysts, and nanotubes. Curl was in India recently to participate in the
95th Indian Science Congress in Visakhapatnam. In an interview to Ashok B
Sharma, he outlines the future prospects of nanoscience and nanotechnology.
Excerpts:
Q.: Can nanotechnology surpass other technologies
in the times to come?
A.: Nanotechnology is the technology for the future generation. It will surpass
all other forms of existing technologies. It can be used not only for industrial
purposes but also in life sciences, particularly relating to drug delivery
at the targeted points in the body.
Q.: How long should we wait to reap the benefits
of this emerging technology?
A.: Nanotechnology is not new. It evolved over billions of years as a natural
phenomenon. In the medieval period of history, there were instances where
nanotechnology was deployed. Many items like the Persian Khanjar and the Damascus
steel were made by unconsciously applying nano technology. The iron ore was
procured from India and processed in traditional way at requisite temperatures
to produce these wonderful items. A hot-forged metal was used in sword making
with its particles in microns-one-millionth of a metre. While examining these
ancient products, we find the existence of carbon nanotubes in them. Tipu
Sultan, the ruler of the erstwhile kingdom of Mysore in India had a sword
made of Damuscus steel. India, too, produced many products by unconsciously
deploying nanotechnology.
In 2006, a team of scientists led by the German
physicist Peter Pauller found presence of nanotubes and nanowires in Tipu
Sultan's sword. According to them, a complex process of forging and annealing,
led the sword's development on nano-scale.
Q.: In which other areas was nanotechnology
used in ancient times?
A.: Yes, there are many more examples. The attractive colouring on ancient
Czech glasses is found to contain nano particles. This shows that nanotechnology
was used for spraying and making a product look attractive. However, over
a period of time this knowledge was lost. Now it is being rediscovered and
reinvented.
Q.: How and when did we rediscover nanotechnology
in modern times?
A.: In 1974, Japanese scientist Norio Taniguchi coined nanotechnology to mean
precision making. Earlier in 1966, the American physicist, Richard Ferynmann,
in a seminal paper-explained the concept of nanotechnology. In 1986, K Reic
Drexier's book-Engine of Creation: The Coming Era of Nanotechnology- was published.
Today, the increasing use of nanoparticles in microprocessors or chips for
electronic devices has been upheld by Moore's law, which says that the power
of microprocessors doubles and the cost of production are reduced by half
in every 18 months.
Q.: What is fullerenes? Has its discovery
helped in the development of nanoscience?
A.: I and my colleagues Harold Kroto and Richard Smalley at the University
of Sussex and Rice University discovered fullerenes in 1985. Fullerenes are
a family of carbon allotropes named after Richard Buckminster Fuller and are
sometimes called buckyballs, when in a spherical configuration. They are molecules
composed entirely of carbon, in the form of a hollow sphere, ellipsoid, or
tube. Cylindrical fullerenes are called carbon nanotubes or buckytubes.
Fullerenes are similar in structure to graphite,
which is composed of a sheet of linked hexagonal rings, but they also contain
pentagonal (or sometimes heptagonal) rings that prevent the sheet from being
planar. Carbon nanoscience is a newer concept, while carbon nanotechnology
is much older. Carbon nanoscience needs powerful tools like structures, synthesis
and uses (nanotechnology). Carbon nanoscience had its humble beginning in
1889 when a US patent was accorded to TV Hughes & CR Chambers for fibre
from swamp gas-CH2. The discovery of fullerenes gave carbon nanoscience a
push.
Nano carbon tubes can be used in electronics,
healthcare, solar cells, light harvesting and composites. Nanotechnology can
address environmental concerns if it's deployed in manufacturing, disposal,
transportation and exposure.
Q.: What are its applications in medical therapy?
A.: Nano particles can act as capsules carrying drugs to targeted points in
the human body. Such nano capsules would be biodegradable and safe and would
not cause any harm to the human body. Among other aspects where nanotechnology
can help is the creation of enzymes synthesing molecules, which would produce
enzymes at the rate required by the human body.
