So if you haven't had your head under a rock, you'll be aware that the last episode of Breaking
Bad aired recently.
Well, as sad as everyone was at Head Squeeze it inspired us to look into the science behind
the show a bit more.
It's also timely as we are all prepared to fight off the first of the season's cold and
flu.
The two are intrinsically linked by synthetic chemistry.
In the states you would be hard pushed to find our favourite decongestant, pseudoephedrine.
The 24 hour shop down the road can't stock it because the government insists that it
can only be sold by a pharmacist and if you do find a shop that can stock it then it's
no doubt out of stock.
Yet now there is a solution: last year, a paper was published on how to synthesise your
own decongestant from crystal meth, which means that one phone call to your dealer and
you are simply a chemical synthesis away from once again have freely flowing nasal passages.
So how do we know that we can make one thing from another?
Well, it's all to do with synthetic chemistry.
Most drugs are made from a sort of carbon skeleton with other bits stuck on it.
The ability to make these structures is what makes its chemistry so interesting and versatile.
Sometimes small changes in this structure can have a big difference, and the carbon
structures of both crystal meth and pseudoephedrine are very similar despite their very different
uses.
That 'oh, aitch' is all that we need to change.
Now we can't just stick an OH on there with a pair of tweezers: if you make a single dose
weighing around 30 milligrams, you would need to do that 900 trillion, trillion times to
get enough molecules - and I don't have time for that!
What we would do in the lab is use something called 'Chromium hexacarbonyl' to bind to
and activate the right point on molecule so we can deliver our small change to all the
molecules in the right location.
We then remove the chromium off the molecules and we have our own personal stash of decongestant.
"Now if you're thinking this sounds all very simple, what made Walter White so special?
Even Jesse could handle this!
Well it isn't actually very simple at all.
Converting off-the-shelf drugs to something with more street value requires specialist
knowledge & ingredients
Red phosphorus is key to the chemistry discussed in Breaking Bad.
But red phosphorus isn't all that readily available.
More importantly, if you do find someone who can sell it to you, it's not before long you'll
find the police turn up and start asking some really difficult questions.
[graphic animation of red phosphorous sitting on a table with a man's head popping up behind
followed by two police guns pointing at him]
You might wonder if 'white phosphorus' would work instead.
Sadly, it's not as easy as that.
Firstly, the difference between red and white phosphorus is much like the difference between
diamond and the graphite -- used to make the lead in pencils.
They're both the same element, but the difference in arrangements of the atoms results in very
different behaviours.
That isn't limited to chemistry, try proposing to the love of your life with a graphite engagement
ring.
The second problem is that white phosphorus is also a chemical weapon, so it's still not
that easy to get hold of...and when you do, it has a nasty habit of just catching fire.
So the quick route of taking one drug and turning it into another has its difficulties.
What about making it from scratch?
Build it up step by step.
That's where Walter White's genius as a really good chemist made him formidable as Heisenberg.
Every step has side-reactions and unwanted products, so some of your expensive starting
'stuff' gets lost on the way.
A really good chemist can minimise these problems, by doing things like not spilling it on the
floor.
But even if they get 90% of their starting material converted into the product at each
step, over 20 steps, that would still mean they only get around 10% of the final product
due to all the losses on the way.
Whether you're a pharmaceutical company or a drug dealer that really starts eating into
your profits
So there you go.
Being a high quality drug dealer is hard.
But if you have a blocked up nose and willing to give it a go, you can always clear those
sinuses.