RE: SciAm: nano

From: Damien Broderick (d.broderick@english.unimelb.edu.au)
Date: Sun Aug 19 2001 - 20:28:38 MDT


I passed along some of the comments from the list to Dr
Vijoleta.Braach-Maksvytis, one of the world's leading nano experts with the
Aussie CSIRO. She sez:

========================================

George Whiteside is the leader (with ourselves!) in the field of molecular
self-assembly as it actually occurs within our current understanding,
particularly from a chemistry perspective, and nanotechnology, i.e.the
understanding of phenomena at the nanoscale dimension and mechanisms by
which nanoscale molecules interact with one another, is precisely his field
of expertise.

Splitting hairs with the ATP argument. ATPase enzyme is embedded in a
biological membrane and is driven by energy produced in the form of a
chemical gradient through the build-up of hydrogen ions, hence it is
chemical energy used to drive the rotation of the protein shaft. Magnetic
field generation occurs during electron transport, which is not occurring
during this process.

There are some very nice examples of work where part of the ATPase enzyme
has been attached to a surface and a small silicon bar or polystyrene bead
is attached to the protein rotor and the rotation of the silicon bar or bead
is observed if you supply the system with the right cocktail of chemical
ingredients. I've attached a PowerPoint presentation from a conference last
year where this work was presented, and it is worth tracking down the
groups because they give some nice moving graphics for this.
 
Scientists like precision in language. 1 micron is 1000 times greater than
1 nanometer, hence perhaps Microtechnology is more appropriate than
Nanotechnology. Also the NSF and other scientific nanotechnology definitions
relate to both size and also the particular properties which are observed
for material at that scale which are not observed for larger-scale, i.e.
micro and upwards, material. Hence when talking about nanobots the word
implies the nano-scale and hence the arguments against such entities being
possible at the nano-dimension.

In conclusion, George does know what he is talking about with regards to
what our current understanding is of mechanisms and what might or might not
be possible based on our current knowledge of scientific principles.

==================

I'm in two minds about her nomenclature argument. It's true in a way that
if working bots are ~1 micron, it's somewhat misleading to refer to them as
`nanobots', even though their *parts* are nano-scale, and they are compiled
at that scale.

Damien Broderick



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