World Of The NANOS-
Part I: A Funny Thing Happened On The Way...
[from TBGS newsletter Spring 2004.]
Conjure up, if you will, several male adults clad in togas,
and reclining on couches. Were they leisurely sipping wine from oversized
goblets? --- reflecting on the prowess of certain gladiators at the Hippodrome?
--- ruminating on the undulating bodily movements of the new dancer from
Thebes? --- speculating about the vintage*,
? --- or, just plain schmoozing ? None Of The Above !
From the comfort of their couches, they were seriously contemplating the
composition of all matter. After all, they, as proponents of deductive
reasoning, considered themselves fully capable of figuring out many
things solely via logical, mental processes - so, why experiment?
But there were also those, if few and far between, who investigated as
well. Democritus (5th century BCE) was such an individual, "acquainted
with the virtues of herbs, plants and stones, and (he) spent his life
(conducting) experiments with natural bodies... wrote books and dissected
animals..." As a disciple of Leucippus, he expanded on his teacher's
conjectures about atoms.
Imagine, how through their mental gymnastics alone, they arrived at such
an abstraction of scientific thought: the impossibility of dividing things
ad infinitum.The least divisible was called the atom. [The
word derives from the Greek atomos = not cut, or, indivisible.]
This "logical" philosophy of atomism by Leucippus & Democritus, 5th century
BCE, was elevated to the status of "scientific theory" some 24 centuries
later = in the early 1800's, by the English chemist, Dalton.
Proceeding along the time-line, in the 1940's, three physicists came up
with what may prove to be the invention of the millenia, the transistor.
Shockley, Bardeen, and Brattain designed the device; almost
immediately, it "gave an unprecedented shock to the electronics industry."
The transistor functions either as an amplifier, or as a switch.
It is solid state, with no moving parts except electrons. A small space
can accomo-date collections of transistors = a descent into the
world of "the tiny."
[ " What,"asks the reader,"are the links betwixt our Grecian friends,
the transistor, and matters biological ?" Read on.. ]
Greeks Had A Word For It ...
prefix, nano, comes from the Greek combining form nanos,
meaning dwarf. Back then, they speculated on what
was "in there." Today, we are actually working "in there." Devices
have become so small that throughout industry the motto is: Iffen you
can see it, it's too big !
The major applications of "the tiny" have been in communications; e.g.,
a telephone is not only wireless, it is also a camera... On the heels
of the transistor discovery, new industries have swallowed up old stand-bys.
Although the original "wave" seems to have peaked, that's not the case
for the "wavelets" - many of them in Life Sciences - that were created
as well. Texas can brag The Strategic Partnership Of Research in Nano-technology,
a consortium including UT's- Austin, Dallas, Arlington, plus Rice and
Antony van Leeuwenhoek's microscope exposed tiny life forms down
to bacteria, parasitic protists, sperm cells, blood cells, microscopic
nematodes, rotifers, and more. [P.S. He did NOT invent the microscope
- just ground better lenses and was more precise than his predecessors.]
methods of probing for smaller and smaller forms uncovered the viruses
- not quite animate - and more recently, the prions.
In 1959, Feynman (physicist) offered $1,000 to the "first guy" who could
produce an electric motor as small as 1/64th of an inch. Well, today the
offer could be for Nano motors about 1,000th of a hair's width.
Torrents of discoveries
stream in: Nano-this and Nano-that. (Where
will they lead us? Hard to foretell. We trust for the better.)
* Flow-Thru biochips - highly porous silicon chip w/huge surface area;can
simultaneously analyze the reactions to a specific substance. of up to
400 known genes By German companies. www.metrigenix.com
* Creation of a Nano bone was reported by China and after it is
implanted, the artificial material "disintegrates" over time and is replaced
by human bone tissue. www.tsinghua.edu.cn/eng
* Internal body scanner named "electrostatic micromachine scanning
mirror for optical coherence tomography" - jointly by Duke and G.Washington
Univ - uncovers surface and below surface internal abnormalities.www.dukenews.edu
* Heightening antibiotic efficiency by uniting it with tiny carbon
buckyballs that can be targeted to attach themselves to harmful, specific
(sometimes antibiotic-resistant) spores. at Rice Univ. www.rice.edu
* A single molecule light emitter= one ultra-tiny, carbon nanotube
mounted on a 3-terminal transistor; simultaneous release of electrons
(-) and plus charges at holes in the tube = light is produced.
* High precision semi-conductor nano-crystals -sized at atom+ level
- called "EviDots" or "quantom dots" to act as fluorescent
or photonic materials in bio-technology. by Evident Technologies
Richard Feynman's 1959 talk
Plenty of Room at the Bottom,"
He envisioned using machinery factories to build smaller factories that
built yet smaller factories... "At each stage, it is necessary to improve
the precision of the apparatus."... leading to nanomachines building atomically
precise products. "What would the properties of materials be if we could
really arrange the atoms the way we want them?"
"At the atomic level, we have new kinds of forces and new kinds of possibilities,
new kinds of effects. The problems of manufacture and reproduction of
materials will be quite different. I am, as I said, inspired by the biological
phenomena in which chemical forces are used in repetitious fashion to
produce all kinds of weird effects (one of which is the author)".
[Here's some Biology: All living things, have their own "nanomachines"
that regularly build more nanomachines- notwithstanding quantum uncertainty
and thermal motion.]
Foresight Institute's K.Eric Drexler (ex MIT)
He introduced the term "nanotechnology" in the mid-1980s describing molecular
assembling devices able to position reactive molecules with atomic precision.
He envisioned such tiny assemblers able to build anything with absolute
precision & with no pollution. [The good.] "Replicating assemblers
and thinking machines pose basic threats to people and to life on Earth,"
he also wrote. [The bad.]
Prof. Richard E. Smalley, Rice Univ
Won 1996 Nobel Prize, Chemistry: discovere fullerenes (aka buckyballs).
Fullerenes are a molecular form of pure carbon discovered in 1985. They
are cage-like structures of carbon atoms, the most abundant form produced
is buckminsterfullerene (C60), with 60 carbon atoms arranged in a spherical
structure. There are larger fullerenes containing from 70 to 500 carbon
atoms. A fullerene can encapsulate an atom, i.e., a nitrogen.
Current research focuses on the potential applications of carbon nanotubes.
( aside: Smalley does not think molecular assemblers in the manner envisioned
by Drexler are physically possible.)
Smalley's dismay is that speculation with regard to potential dangers
(that could stem from misapplications of nano) tends to threaten (scare
away) public support for nanotechnology. The novel, "Prey," by Michael
Crichton is a case in point.
He writes: "...join with me in turning on the light, and showing our children
that, while our future in the real world will be challenging and there
are real risks, there will be no such monster as the self-replicating
mechanical nanobot of your dreams.
C & EN
December 1, 2003 Volume 81, No. 48
CENEAR 81 48 pp. 37-42 ISSN 0009-2347
[the article above is from the TBGS
newsletter Spring 2004.]