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Chemical Technology • November 2015
7
NANOTECHNOLOGY
making copies of itself…the first replicator assembles a copy
in one thousand seconds, the two replicators then build two
more in the next thousand seconds, the four build another
four, and the eight build another eight. At the end of ten
hours, there are not thirty-six new replicators, but over 68
billion. In less than a day, they would weigh a ton; in less
than two days, they would outweigh the Earth; in another
four hours, they would exceed the mass of the Sun and all
the planets combined— if the bottle of chemicals hadn’t
run dry long before.”
This doomsday “grey goo” would – wait for it – wait for
it – threaten life on earth.
On the other hand, Spiber, a Japanese company, has just
developed the first artificial spider silk fibre which they’re
called Qmonos. The fibre is produced during a fermenta-
tion process led by genetically engineered yeast producing
recombinant proteins. They spent 11 years on this, using
656 gene synthesis designs.
It turns out, however, that you can’t just make the pro-
teins and expect proper silk to result. As
dre85
notes on
Hacker News, “… expressing the proteins is the easy part.
Spinning the proteins into a thread was the tough part. Ap-
parently spiders have special excretion structures/organs
that can anneal the proteins to the right conformation ex-
tremely quickly as they are ejected. This is why a spider can
basically just jump off of anything and shoot out his ‘bungee
cord’ while falling which is incredibly fast if you think about
it. When the researchers tried to replicate this by simply
shooting the concentrated protein solution through a tiny
capillary they weren’t able to achieve the same molecular
structure for their thread nor at the same speed. They noted
that their thread was strong, but nevertheless significantly
weaker than a spider’s.”
Spiber are partnering with North Face to produce The
Moon Parka, a product that is to go on tour later this year
and which you may be permitted to buy in 2017.
I do like the idea of spider-silk clothing. But imagine the
same material used to repair injuries? It should be as bio-
compatible as silk. “It’s hard to see unless you look closely,
but this is the beginning of biological nanotechnology. These
are some of the very first deliberately designed biological
molecules to make it into a non-pharmaceutical market.
Technologically, the silks in these fabrics are made of
designed components an order of magnitude smaller than
Intel’s best transistors. And (under biological conditions)
are significantly more functionally versatile,” says
toufka
,
also on Hacker News.
Yes, and that’s the grey goo problem. Since the machines
are actual living organisms, they might be able to reproduce
outside of the factory. Spider silk fabric is nice. Spider silk
clogging up our waterways, or being excreted as waste by
some infectious illness; not so nice.
And yes, we’re definitely on the cusp of something incred-
ible which will change our experience of healthcare, as well
as the world in which we live. As the nanomachines we want
to build, or the scale of action we wish to take, shrinks and
becomes more complex, we are definitely going to find it
easier to work with genetically engineered organisms who
will build things for us.
We’re looking at nanomaterials which need to be deliv-
ered as a payload to a specific activation site in the body,
without triggering an immune response or getting lost. We