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Saturday, March 26, 2011

POLYMORPHISM - PROFESSOR CHICK WILSON AT THE ROYAL PHIL

   On Wednesday I attended the Royal Philosophical Society of Glasgow lecture by Professor Chick Wilson of Bath University. I had a question at the end which I think suggests a considerable possibility.

Chemists usually know what molecule they are going to make and make it. Great, but nature has the habit of biting back. Sometimes the molecules go wrong, in something as simple as the order in which atoms join to a carbon. When this affects the handed-ness of the molecules (yes, molecules can be left or right-handed), this is called 'enantiomerism'. Sometimes the molecules are right but the way they stick together is wrong. This phenomenon is known as 'polymorphism'.
These examples of molecules behaving badly can have dramatic effects, and we might want to ask questions like:
Ever wondered why chocolate goes white with age?

Have you heard of the thalidomide tragedy?

Did you realise that a major US pharmaceutical firm recently lost over $250M because the molecules of an anti-HIV drug started sticking together badly?
  This is ROY. It is all one chemical with a long name I have no intention of remembering. This name comes from Red Orange & Yellow the various colours the 7 atomically  identical varieties come in.

The best known multiple morphings of a material is in organic chemistry (ie involving carbon) where soot, graphite, diamond and buckeytubes are all different arrangements of carbon atoms. Another is water ice of which there are currently 15 types known created by an incredible range of temperatures & pressures over differing times with different catalysts. Fortunately none of them have the fictional properties of Vonnegut's Ice 9 written about in 1963

Professor Wilson had a number of remarkable stories.That there are 2 morphs of thalidomide, though unfortunately the safe type morphs into the dangerous one inside the human body so neither is ultimately safe.

In many cases one morphic state will, over time metamorphosises into another, normally the one with the highest melting point being most stable, which is why chocolate ages.

The $250 million blown example (actually they spent a lot more finding why) is of an anti-AIDS drug called Ritonavir whose manufacturers had 2 factories producing it - one in the US & the smaller one in Italy. One day the former started producing a different & useless state of the same drug and not all the huffing and puffing by the manufacturer could make it start producing the desired morph. But the Italian factory was still working normally. So they got all the chief scientists and sent them off, in their white coats, to find out what the Italians were doing right. And as soon as they got there the Italian plant started producing the wrong morph too. What happened is that the molecule sized pieces of the undesired morph had infected the Italian plant, ad it had previously done in the American.

   This is an example of the "universal seeding hypothesis" that there must be some such states of crystallisation whose atoms are so endemic across the planet that they already prevent different morphs appearing.

    Thus it is impossible to predict what morphs may be possible, let alone what their states might be though, as with ritonavir some currently useless materials may be incredibly valuable.

    Which brought us to the Q&A session and my question.

    "One of my hobbyhorses is space industrialisation and it strikes me that it is likely that zero gravity will allow the manufacture of many materials either not possible here or incredibly expensively. Do you think this is likely"

    He enthusiastically agreed that there were bound to be many such. He didn't know of any yet but experience shows it is easier to grow large crystals in zero gravity so it is virtually certain that this will be a common property of such chemicals. He also mentioned a colleague who is trying to get an experiment to Mars where gravity is 0.38 of ours to see how it affects such growth.

    Afterwards I asked him a little more. Does he know of any such experiments to deliberately create new morphs in orbit - No he didn't. Did he know of any attempts to do so in a "vomit comet" - No and it probably wouldn't work because in such a plane, with engine vibrations etc, it would be impossible to control the other factors thoroughly enough.

    However I have elsewhere suggested that the greatest ultimate profits to be made in space will not be from solar power satellites or even asteroid mining, both of which provide a potential step reduction in costs of something we already do, but in manufacturing materials, such as large crystals or foamed metal beams which we simply cannot do in a gravity field. Polymorphism seems to radically increase the number of materials we can make in orbit which are either impossible or horrendously expensive here. Hank Stine's book, the 3rd Industrial Revolution detailed many possibilities of such materials that could be made but studies of polymorphic materials has gone a long way since then. I may well be going over ground that others have but it is certainly not a well trodden path. Until they have been made nobody can say what properties will be found or what value they will have but if we are talking about varieties on the order of a large fraction of all the materials we can make on Earth there are bound to be enormous opportunities waiting.

   There may also be materials that not only can only be created in orbit but would only retain stability there. Not something which would be any use today but would have consequences for the long term development of orbital living.

   Another advantage in orbital industries would be the ease with which stations could be sterilised and remain isolated - which affects the panspermia option. Also it is easier for orbital industries to vary such things as temperature and pressure than on Earth.

    Regarding the "vomit comet" option I do not know if, in all cases, the restriction of operating in an enclosed space would prevent the manufacture of morphic materials. In particular I am thinking of the SR 53 option of a suborbital craft, which would fly outside the atmosphere, thus beyond the vibrations caused by atmosphere or engines, though not into orbit. It was advertised to Parliament by Dr Collins as being able to carry a larger than man sized automated production package for about £3,000. It seems likely that  this wold provide a number of real commercial opportunities

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Nice article, thanks for the information.
 
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