🚀 go-pugleaf

nsmca@acad3.alaska.edu writes:

>Does nantech machines have to be mechanical? or can they be
>genetic?? 

Ultimately nanomachines will be mechanical, since we can then
use a much wider range of molecules than biology currently
uses.

For now, the path to full Drexler nanotech is following
two major threads.  The first of these is scaling of lithography
down to the "deep sub-micron" scale, for the manufacture of
quantum dots, designer catalysts, and minitiarized circuitry.
Within a decade, we may see AFM arrays or other techniques used
to mass-produce chips a 10 nm scale.  The second is biotechnology, 
with liposomes (drug-carrying artificial membranes), monoclonal 
antibodies (cells programmed to be triggered by specific molecules), 
polymerase chain reaction (self-replication of DNA outside the cell, 
greatly accelerated over what nature can do), and gene-splicing
as the basis for two new fields, protein engineering and metabolic
engineering.

We can already see these two fields starting to merge.  Lithography
is being used to program arrays of chemical reactions, for use
in DNA sequencing, designer polymers, etc.  Enzymes (protein
catalysts) have been built into clay structures; these molecular
cyborgs now help make such ubiquitious products as the corn syrup in 
your Pepsi.  Soon we will see enzymes designed on a computer,
programmed into DNA by wet-array-lithography, mass produced by 
gene-spliced bacteria, and then hooked onto lithographed structures
to form catalysts orders of magnitude more proficient than today's.

On the horizon are molecularly precise resists, or "nanoresists", 
for nanoscale lithography.  Within two to three decades, lithography 
combined with a bit of post-processing will likely be able to produce 
molecularly precise parts, at which time we can start building mechanical 
machines and proto-assemblers along the lines Drexler envisions.  In 
the meantime, biotech and lithography may bring many of the benefits
ultimately envisioned for nanotechnology.


-- 
Nick Szabo					 szabo@techboook.com