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The Crystal That Could Destroy All… — Veritasium shadowing | TryShadowing
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Veritasium
The Crystal That Could Destroy All Medicine
The Crystal That Could Destroy All Medicine
Veritasium
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33:24 · Apr 29, 2026
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-
For
two
years,
this
drug
was
a
miracle.
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Original
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1
/637
0:00
- For two years, this drug was a miracle.
0:03
It was introduced in 1996 to treat HIV.
0:06
And by 1998, 75,000 patients across the country were taking up to 20 of
0:11
them every day.
0:12
It's called ritonavir, and it turned a certain death into a manageable condition.
0:19
This particular pill is on its way to quality control to a dissolution tester.
0:23
Here, analysts monitor each batch of capsules,
0:27
checking that they do dissolve in around 30 minutes,
0:29
which is quickly enough to be absorbed properly.
0:32
It's a rigorous precaution for a drug
0:34
that for two years
0:35
and 240 consecutive lots has never failed. (grim music)
0:41
But now an analyst sees something unusual.
0:44
This capsule hasn't dissolved properly.
0:47
So they follow protocol
0:48
and trigger an emergency shutdown. (alarm blaring) They destroy the entire batch
0:54
and deep clean the production line to eliminate any possible traces of contamination.
0:59
But the next day, at quality control, the same thing happens.
1:03
On the line the clear capsules are turning white and cloudy,
1:07
technicians at the nearby research
1:09
and development lab study the paste under a microscope
1:12
and find they're filled with millions of tiny needles.
1:16
They're crystals, but no one has seen them before.
1:19
They need a control to compare the needles against,
1:23
so they make some of their own ritonavir in the lab,
1:26
but to their horror, it also comes out cloudy.
1:29
So they try again, but all attempts yield the same result:
1:34
a white paste every time. (subdued music) The researchers are stumped.
1:39
They had been making ritonavir for two years.
1:42
They knew its exact chemical composition
1:45
and every part of the process used to make it,
1:48
so they check all the input ingredients again, all the settings,
1:52
every temperature setting and procedure.
1:54
But all of it seems to be done correctly.
1:57
Yet at the factory, the cloudy capsules are appearing more and more frequently.
2:02
Within a week, every tablet produced by either the lab
2:05
or the factory comes out cloudy.
2:08
Abbott needs to halt all production of ritonavir immediately.
2:12
But they can't just cut off the supply
2:14
because people need these tablets. - "We called on
2:18
as many resources as we could.
2:20
We tried everything.
2:21
We conducted countless experiments.
2:23
We rebuilt facilities and new lines.
2:25
We looked at alternative sites to see
2:28
if we could start clean in a new environment." (gentle music) -
2:32
And they found an alternative site,
2:34
a factory in Italy.
2:36
They start ritonavir production there, and to their relief,
2:39
all the pills passed the dissolution test.
2:41
This is great news.
2:43
But it also means that Chicago must have been making a mistake.
2:47
So a team of scientists flies over to look at what the Italians are
2:51
doing differently.
2:52
They check everything, the pressure, temperature, humidity, the exact weight of all the chemicals,
2:58
but it all matches perfectly with what they're doing in Chicago.
3:02
None of it makes any sense.
3:04
But at least Italy can keep making the medicine. (phone ringing) (soft brooding music)
3:08
But when the Chicago team returns home,
3:11
they get a call.
3:12
It's from Italy.
3:13
Within days after their visit,
3:15
one of the tablets fails the dissolution test. - "There was no gradual trend.
3:21
There was no early warning.
3:22
In a matter of weeks, maybe five or six weeks,
3:25
every place the product was became contaminated with the crystals.
3:29
We did not know how to detect it.
3:31
We did not know how to test for it.
3:32
We did not know what caused it.
3:34
We did not know how to prevent it.
3:36
We did not know how to get rid of it.
3:38
And we kept asking the question,
3:41
'Why now?'" - They were witnessing a rare disaster.
3:47
It had happened before,
3:48
and in theory could happen again to just about any drug or chemical compound.
3:53
It spreads like a disease, but the thing that's getting infected is the medicine.
3:58
One day you can make it,
4:00
the next it's gone forever. - "It is frightening
4:03
that this could happen to any drug
4:05
that we've taken on,
4:06
which we're dependent." -
4:07
And the scariest part is you can't predict
4:10
if it will happen,
4:11
when it will happen, or to which medicine or compound.
4:15
Overnight, drugs we all rely on might just disappear.
4:20
So what was happening inside those ritonavir capsules?
4:23
What were those crystals inside?
4:25
They appeared to be an entirely new compound, but when they tested them,
4:30
everything indicated they were ritonavir.
4:33
It sounds impossible, but something similar had actually been the center of a heated
4:37
debate 170 years earlier. (mellow music) - In his Paris laboratory,
4:43
chemist Justus von Liebig was reading a paper.
4:47
It was about a newly discovered compound, and what elements it was made of.
4:51
This kind of work was at the cutting edge of chemical research.
4:55
Research he knew better than almost anyone
4:57
because he had personally pioneered most of it.
5:00
This had made him highly respected in his field,
5:03
but he also had a reputation for being difficult to work with.
5:06
He was arrogant, hot-tempered, and didn't suffer fools.
5:10
And the more he read this paper, the more incensed he got,
5:14
because to him, it was clearly written by a fool, Friedrich Wöhler.
5:20
So we headed over to the lab at Imperial to recreate what Wöhler claimed
5:24
to have discovered. -
5:25
So I've got it here wrapped in foil
5:27
because it is a bit photo-sensitive. - It's a bit like,
5:30
like, little rocks in there. - Yeah. - Beige powder, okay.
5:34
Made of one silver, one nitrogen, one oxygen,
5:37
and one carbon. - Exactly. - (laughs) You wanna light it up? - Yeah, sure,
5:40
let's do it.
5:42
You seem quite excited. - I am quite excited.
5:47
Yeah.
5:48
Not much is happening.
5:50
Oh, it's melting a little, or it's, like,
5:53
it is getting a little discolored. - Yes,
5:55
it is. - I guess the issue was he said, "Okay,
5:59
I found this beige powder and I know exactly what it's made of,
6:02
one silver, one carbon, one nitrogen, and one oxygen."
6:05
He publishes this. (curious music) The paper reaches Liebig, and he is like,
6:10
"There's no way, because I've just discovered that compound.
6:13
And when I tried to put a flame to it, it behaves completely differently."
6:18
And we've got some of
6:19
that right here too. (serious music) Should we try to burn this one? -
6:22
Yeah.
6:23
I made some fresh this morning.
6:24
Let's just see how a small amount behaves.
6:26
So we're gonna go with, I don't know, maybe a few milligrams.
6:30
I've left it a bit moist.
6:33
When it's in its moist- (compound snaps) Oh! - Oh, my God.
6:36
I didn't expect that. - Yeah! - It's so loud.
6:40
(Dr.
6:40
Kafizas laughs) - It's very sensitive.
6:42
I'm sorry about that. -
6:43
That is crazy. -
6:44
And that was just a small amount. - Oh my God,
6:46
my ears.
6:47
What?
6:47
I was not ready for that. - I wasn't ready for that either.
6:50
I made it moist so that it's less likely to self-detonate,
6:54
but clearly I was wrong. - Clearly Wöhler had made a mistake.
6:59
These can't possibly be made of exactly the same elements.
7:02
So Liebig wrote a paper slamming Wöhler's work,
7:05
calling him a "hopeless analyst" and saying he should go back, check his work,
7:10
and publish again when he's found his mistake.
7:13
And Wöhler does exactly that.
7:15
He checks his work but finds no mistakes.
7:18
So now he's even more sure that he's correct.
7:21
So he writes up his results in a second paper,
7:24
but Liebig wasn't having any of this
7:26
and replies with another paper saying he must be wrong.
7:29
So this public back-and-forth continues for two years,
7:33
with each side becoming more
7:34
and more convinced that the other is out of their mind,
7:37
until finally they agreed to meet on neutral ground in Frankfurt to put this
7:42
whole thing to bed once
7:43
and for all.
7:44
They would replicate each other's work and let the results speak for themselves.
7:48
But when they did, they were stunned.
7:52
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9:35
And now back to what was happening with Liebig
9:38
and Wöhler. (soft music) - They were both right? - Yeah. - Like,
9:45
they both had a compound that was made of exactly one carbon, one nitrogen,
9:48
one oxygen, and one silver atom.
9:50
And one could be boring as hell (laughs) and the other one can, well,
9:55
blow up your face. (compound snaps) - Oh!
9:59
(compound bangs) - Whoa!
10:01
(laughs) - This was surprising
10:03
because at the time a compound was thought to be just the atoms
10:06
that made it up
10:07
and nothing more.
10:08
But now this whole conception had to change.
10:12
Von Liebig and Wöhler had discovered
10:14
that the way those atoms are arranged also matters.
10:18
At the time, they had no way to work out that ordering,
10:21
but today we can. (inquisitive music) When you shine light on a molecule,
10:25
its electric field tugs on the electrons and nuclei.
10:29
They get pulled back and forth as the field changes direction.
10:33
This can stretch, squeeze,
10:34
and bend the bonds in the molecule as the atoms oscillate back and forth.
10:39
But each bond responds differently to the light depending on how strong it is
10:43
and the mass of the atoms it connects.
10:45
It's like each bond is a boat on the ocean.
10:48
If the waves are small and rapid, they won't rock it very much.
10:53
And if the waves are very slow, like the tides coming in and out,
10:56
that also won't rock the boat very much.
10:59
The boat just gets lifted up and down.
11:02
It's only when the waves are just the right size
11:04
that the boat gets tossed around.
11:07
And because of this,
11:08
each bond will react strongest to a specific frequency of light,
11:11
which we can measure.
11:13
By hitting the molecule with a range of infrared frequencies,
11:16
we get a spectrum like this with peaks
11:19
that tell us when bonds are reacting.
11:21
This acts like a fingerprint for the molecule
11:24
and tells us which bonds are there.
11:28
Wöhler's compound has a broad peak,
11:30
which corresponds to bending an N double-bonded to C double-bonded to O group.
11:35
Liebig's compound, on the other hand, has a spectrum that looks like this,
11:39
with these two prominent peaks, one at high frequency and one at low frequency.
11:44
These correspond to stretching a double bond between a carbon
11:46
and a nitrogen and a single bond between a nitrogen
11:49
and an oxygen.
11:51
We now know that Wöhler's compound was silver cyanate,
11:54
and it looks like this.
11:56
The carbon, nitrogen, and oxygen are joined with those two strong double bonds,
12:01
which is why it's so stable.
12:02
In contrast, Liebig's compound, silver fulminate, looks like this.
12:07
The silver is bonded to the carbon instead,
12:10
so the other elements are arranged this way.
12:13
The bond between the carbon and nitrogen is a triple bond,
12:16
but the oxygen and nitrogen are very weakly connected.
12:20
And this single bond is very easy to break, and once it does,
12:24
the atoms can rearrange into much more stable gases,
12:27
which is why it's so explosive.
12:30
They had discovered isomers.
12:32
That it's not just the atoms in a molecule that dictate how it behaves,
12:36
but its bonds as well.
12:38
So naturally the scientists at Abbott suspected something similar might be happening to ritonavir.
12:44
They knew that the spectrum of ritonavir should look like this.
12:48
So they put a sample of white paste into a spectrometer,
12:52
expecting to see something completely different.
12:54
But instead they saw this, the same peaks.
12:59
The paste had all the same bonds as ritonavir, so it must be ritonavir.
13:05
But they also noticed it wasn't exactly the same.
13:08
There were these small deviations between the two.
13:11
The arrangement of the atoms was the same,
13:13
but something about the bonds had changed slightly. - Well,
13:18
it turns out there's another way to change the properties,
13:21
and I can show you how with probably the most delicious demo I'll ever
13:25
do,
13:25
because this, of course, is a piece of chocolate.
13:28
It's nice, it's shiny, it's durable,
13:31
and it has that nice snap when you crack it.
13:34
But you'll notice that if you've ever let your chocolate melt,
13:37
then it never returns to being quite the same.
13:40
Suddenly it melts in your hand when you pick it up, you know,
13:43
it's dull, it's bendy, and it doesn't quite taste the same.
13:46
You're not imagining this.
13:48
There really is a subtle difference,
13:49
and I can explain what's happening with a little help from my friend Chris
13:53
over here. - Hey. - Hello.
13:54
So Chris runs his own YouTube channel, Chris Young Cooks,
13:58
and this is way overkill for what we need here probably,
14:00
because he was the head development chef at a three-Michelin star restaurant. - Yes.
14:06
(subdued music) - We've got some nice shiny chocolate here.
14:08
But look what happens
14:09
when we turn up the heat. (heat gun whirs) Oh yeah,
14:19
that goes quite quick.
14:23
Oh, that is surprisingly satisfying. - We obviously melted some of the chocolate, no surprise.
14:30
But this is what happens, right?
14:31
You leave it somewhere warm, the chocolate gets above body temperature,
14:34
it starts to melt, and then as it cools back down,
14:36
it's gonna harden again. -
14:37
So you've got the chocolate. -
14:39
That looks like heat-damaged chocolate,
14:41
right? - I know. - Like, you've seen this, you've opened a chocolate bar,
14:44
maybe it was left in your car sitting in a sunny window.
14:46
Touch the edge, like, you can feel,
14:50
feel how that's just soft- - Yeah. -
14:51
and kind of sticky. - Immediately. - Compare it to a nicely tempered piece
14:56
of chocolate.
14:56
Like, you can pick that up with your bare hands,
14:59
it will eventually melt in your hand,
15:00
but much more slowly. - Now if this ever accidentally happens to you,
15:04
we'll show you how to get it back to the nice and shiny form.
15:08
But what's interesting here is
15:09
that we didn't change any of the ingredients
15:12
and yet the properties changed completely.
15:15
Chocolate is made of three main ingredients.
15:17
There are other minor ones as well, but three main ones to focus on.
15:21
It's got cocoa solids, that's what gives it its color, there are sugar,
15:25
of course, for sweetness, and then there is cocoa butter.
15:28
That's what gives it its texture. (gentle music)
15:31
And this cocoa butter is the culprit.
15:33
It's a fat made from three long carbon chains bonded together in the middle
15:37
to make this sort of Y shape.
15:40
And that Y shape can form together to form solids.
15:42
But there are multiple ways they can stack together.
15:45
There are many forms the crystal can take, each with different properties.
15:49
And so we call these polymorphs.
15:52
Chocolate actually has six polymorphs.
15:55
The dull chocolate is mostly Form IV,
15:57
and that has a melting point of around 27 degrees Celsius.
16:01
While the shiny chocolate, which is the one we want, is mostly Form V,
16:05
and that has a higher melting point of around 34 degrees Celsius. -
16:09
So the challenge and the art of chocolate making is managing these polymorphs to
16:14
get the right form of crystal by managing both temperature
16:17
and,
16:18
importantly, time.
16:19
The nice thing about chocolate is you can start over.
16:21
You just need to heat it back up to 45 to 50 Celsius to
16:24
wipe the memory- - Okay. - of the wrong crystals.
16:26
That's hot enough to melt out all of the crystals,
16:29
but not too hot to start changing the flavor of the chocolate,
16:32
evaporating a lot of the volatile aromatics. - After around 10 minutes at roughly
16:37
50 degrees Celsius,
16:38
all the crystals should have fully melted. - So at this point,
16:41
we're trying to cool it back down to the temperature where crystals start to
16:45
form again.
16:46
And that's gonna start at about 34 Celsius.
16:48
You'll start getting Form V crystals forming at 34, as we cool even lower,
16:52
we start to get Form IV and Form III.
16:55
Those can all form at these temperatures.
16:57
And that's okay.
16:58
We want all of these crystals initially.
17:00
We want- - Oh, really? - Yeah,
17:01
we want to have sort of a shotgun of nucleation going on
17:05
because we wanna make sure we get lots of everything. - That's surprising. -
17:09
It does seem surprising. -
17:11
Because we just want Form V,
17:13
right? - We do just want Form V.
17:14
The trick is, if we just come down to the temperature where Form V
17:18
forms,
17:19
so if we just went to like 32 degrees, 33 degrees,
17:22
and just waited there,
17:23
you'd be waiting a very long time
17:24
and you'd get a very random process of
17:27
when does that crystal form,
17:28
and maybe only a few crystals would form.
17:30
And so they would get very large. - Ah. - By bringing the temperature
17:33
all the way down to 27,
17:34
we get lots of nucleation really fast.
17:36
The downside, of course, is we get the crystals we don't want as well,
17:40
but we get lots of Form V,
17:41
and we get lots of small Form V. - Yeah. -
17:43
So once we have
17:44
that starting to form,
17:46
we can select for the ones we want just by raising the temperature back
17:50
up.
17:50
And melting the Form III and Form IV, leaving us with only Form V,
17:54
but, importantly, lots of Form V. - Right.
17:57
After holding the chocolate at around 32 degrees Celsius for 5 to 10 minutes,
18:02
we can pour it into the mold. - Okay,
18:04
I think we're gonna be okay here, so. - Oh.
18:10
I don't know what I was expecting,
18:11
but I was not expecting it to go like this.
18:13
It really comes out
18:14
as a sort of sheet. - One of the things here is I do
18:19
have some trapped air bubbles. - Yep. - Oh,
18:28
yeah. - It's like a liquefaction. - Yeah, yeah. - So at this point,
18:35
seems like we're done,
18:36
right? - Yeah. -
18:36
But actually now we need to lock in
18:38
that crystal pattern that we've created,
18:40
right? - Yep. - Like, as it cools down,
18:42
there's liquid oil in there
18:43
and we're gonna drop back down through the temperature where Form IV
18:45
and Form III can form. - Yep. -
18:47
So what we need to do is we need to come down through
18:49
that temperature relatively quickly
18:51
so that we get mostly Form V growing
18:54
and lock them in by getting rid of most of the liquid oil.
18:57
So we really need to get this down to about 12 C. -
19:00
So we put it in the fridge
19:02
and waited for around 20 to 30 minutes. - Get the door closed. -
19:06
Great.
19:08
If we did this correctly, it should be mostly Form V,
19:12
which means all the molecules should have stacked tightly together,
19:15
resulting in a shiny and snappy bar. (tray cracking) Ah!
19:18
Ooh!
19:20
That was satisfying. - They're just barely hanging on. - Wow! -
19:24
And you can see they're nice. - Perfect. - Shiny. - This is all
19:29
Form V? - This is all Form V,
19:32
and we've got a nice shiny surface.
19:35
Got a couple spots where maybe the molds could have been polished a little
19:37
bit more,
19:38
but give it a snap, just see how that is. (chocolate snaps) - Ooh.
19:41
It's a very good snap. - Yeah,
19:42
that's a nice. - It's very sturdy. - That's a good chocolate bar. -
19:48
Delicious. - That is how you temper a chocolate bar. - Amazing. (curious music)
19:51
- But the stacking of the molecules in the crystals also changes something else.
19:55
Since each molecule is surrounded by other molecules,
19:58
it changes how the bonds inside can move.
20:01
This is what the scientists at Abbott had seen in the spectrum.
20:04
The needles they had seen under the microscope were a new polymorph of ritonavir,
20:09
and a more stable one at that.
20:11
Form I crystals looked like this instead.
20:15
Now at first this might seem like good news.
20:17
It was still ritonavir, even if it looked a bit different.
20:21
It's just like how dull chocolate, even if it's not quite as nice,
20:24
is still chocolate.
20:26
But the problem was this new polymorph was far too stable. - Ritonavir Form
20:32
II is substantially more stable than Form I.
20:37
And the way we know it's more stable is because it's less soluble.
20:41
But if that crystal structure happens to be much more stable,
20:46
then it won't dissolve properly.
20:49
And then it's a bit like you haven't taken the drug at all. -
20:54
But with chocolate,
20:55
we can change which polymorph we have.
20:57
We just had to heat it up to switch it from shiny to dull,
21:00
and then by cooling it down again in a specific way,
21:03
we could get back to shiny.
21:05
So you might expect that Abbott could just do something similar with ritonavir.
21:09
And they tried, but the problem was
21:12
that no amount of heating
21:14
or cooling could turn Form II back into Form I.
21:18
They were stuck.
21:19
We can see what's happening by taking a look at this here.
21:24
See, each polymorph has different energy levels.
21:27
And in the case of chocolate that looks something like this,
21:30
where Form IV has a higher energy level and Form V a lower one,
21:34
and they're separated with this sort of hill in between.
21:38
Now, after heating up the chocolate bar, we were mostly left with Form IV.
21:42
So let's drop this little ball in there,
21:45
and then you'll see it will slowly settle down into that valley.
21:51
But not to the more stable Form V.
21:53
And that's because there's this little hill in between.
21:56
But now imagine adding some heat to this.
21:59
It's like giving the ball a little bit of a kick.
22:02
And you can see that the ball will suddenly start to move around.
22:05
And if I give it enough of a kick, whoop,
22:09
it will roll down into Form V.
22:11
And now it is stuck there.
22:13
Now you could keep adding more heat
22:15
and you could get it back over the hill back to Form IV,
22:19
but then you would just end up with a mess of both forms,
22:23
because whenever you start cooling it down again, you know,
22:25
the ball could just randomly settle in one of the two valleys.
22:28
So that's what happened when we melted the chocolate uncontrollably.
22:31
We just got a mixture of these two forms.
22:34
But with ritonavir, the situation is a little different.
22:38
The hill between the two forms is now much taller,
22:41
but the Form II valley is also much deeper.
22:44
So once the ball does get down there,
22:46
it's basically impossible to get it back out of there,
22:49
which is why no matter what the scientists at Abbott tried,
22:52
they couldn't get back to Form I. -
22:57
But this still doesn't explain why Form II was suddenly everywhere.
23:01
Nothing had changed in their procedures.
23:03
The barrier between the two forms should still be there.
23:07
So it shouldn't have been possible to make this much Form II at all.
23:11
And yet, 300 years earlier,
23:13
legends of such a transformation spread across northern Europe. (gothic music) - It was
23:18
a bitter winter morning,
23:20
and it had been like this for months.
23:22
The organist was on his way to a cathedral.
23:25
The cold had been messing with the organ pipes.
23:27
It's gone out of tune again.
23:29
But that wasn't what the congregation thought.
23:32
There were stories of other organs getting sick with warts
23:35
or leprosy eating away at the pipes.
23:39
Some thought it was the devil attacking the organ to punish an unfaithful flock.
23:45
It was even said that when it was very quiet,
23:48
you could hear these organs screaming and groaning in pain from the lesions.
23:54
Nonsense, of course, it was just the metal contracting
23:57
and expanding. (subdued music) Except these pipes weren't just contracting,
24:03
they were cracked.
24:04
And others are indeed covered in what looks like these lesions,
24:08
black growths all over the organ. (dark music) Now, originally when this happened,
24:18
people thought that this was the work of Satan.
24:21
Of course, that's not what was going on,
24:23
and we can explain what was actually happening.
24:25
So we've got some normal tin right here,
24:28
which is what those organ pipes were made out of.
24:30
It kind of looks silver, it feels pretty strong,
24:34
and it's sort of the form we're used to. - Exactly. -
24:37
But here we have a slightly different form of tin.
24:40
You can look at it, it's a bit more gray,
24:43
it's a bit more crumbly.
24:45
And at room temperature, normally the silvery tin is sort of more stable.
24:50
But if you cool tin down to something like below 13 degrees Celsius,
24:55
and ideally way colder,
24:57
then it can transform into this new kind of gray tin.
24:59
And we're gonna see what happens
25:01
when we put it on top of the silver tin. - We want to
25:04
try and get it to around minus 30 degrees Celsius. - Yep. -
25:07
And what better to get us to those temperatures is dry ice. - Okay.
25:11
- So dry ice is frozen carbon dioxide.
25:14
And that is around minus 78 degrees Celsius. - Yep.
25:18
Now we've taken a thermo flask and filled it up with dry ice,
25:21
and then put a platform on top on which we'll put our tin.
25:25
This should cool it down to around minus 30 degrees Celsius.
25:29
Now we left this here for around 14 hours,
25:32
and what you'll see is
25:33
that initially there's a very tiny speck of tin
25:36
that suddenly transformed into gray tin,
25:39
and then it spreads from there almost like an infectious disease,
25:43
which is why this is also known as tin pest.
25:47
And because gray tin is less dense, the tin expands.
25:50
And so if you look closely,
25:52
you can see it start to tear apart the metal.
25:56
Now, normally it takes a lot of energy to transform some silver tin into
26:01
gray tin,
26:02
but once you get a tiny bit of gray tin, something strange happens,
26:06
because now it acts as a nucleation site that other tin can attach to,
26:10
and it effectively brings that hill way down.
26:13
It lowers the activation energy.
26:15
And so now it becomes very easy to switch from silver tin to gray
26:18
tin.
26:18
And so it starts to spread, it starts to take over.
26:23
And the same thing was happening to those organ pipes.
26:25
Once you got a lesion on one of those pipes,
26:28
well then it would grow and spread everywhere.
26:30
Little flakes would come off the pipes and seed all the others,
26:34
and it would spread.
26:36
And that's also exactly what happened with ritonavir.
26:40
Once a tiny bit of Form II appeared, it acted as a nucleation site,
26:44
lowering that massive activation energy
26:47
and causing all the Form I to crystallize into Form II.
26:51
Tiny seed crystals then broke off, could become airborne, and spread,
26:56
attaching themselves to people's clothes
26:59
and making it to other parts of the production line,
27:02
effectively seeding them so that when new ritonavir was synthesized,
27:07
it contained these seed crystals and turned the entire capsules into Form II.
27:12
And because everyone likely had these seed crystals on their clothes,
27:16
when the Chicago team flew over to Italy, they seeded that factory too.
27:22
And in this way,
27:23
soon not a single place was able to manufacture Form I. - Ritonavir is
27:29
arguably the most dramatic case of what we now call a disappearing polymorph.
27:34
The YouTube channel Reactions made a great video about this
27:37
that involves lots of physical demos,
27:39
so I highly recommend you check it out. - "When this happened to us,
27:43
we conducted an extremely thorough investigation to see
27:46
if there was something
27:46
that we did which would have caused this.
27:49
While we've speculated on the cause of this chemical transformation,
27:52
we do not have conclusive proof of what happened." - It might be
27:57
that a mistake on the production line caused some chemicals to dry out.
28:01
This might have created a new crystal similar in shape to Form II ritonavir,
28:06
which acted like a seed.
28:08
Or it might have just been bad luck
28:10
that a seed crystal formed on its own purely by chance. - Even
28:14
if you have a seed crystal,
28:16
if there are some dust particles
28:18
or some scratches in the recipient where actually crystals can start to nucleate,
28:28
that can induce, then, different crystal structures.
28:30
So it happens that in some pharmaceutical companies where they produced the same polymorph
28:37
for years and years,
28:39
that suddenly there is, I would say, a hair or some other particle that,
28:44
kind of, gets into the process
28:46
and will change the entire crystallization of the compound,
28:51
and is then very difficult to control. -
28:54
And once a more stable form has appeared,
28:56
it can spread and quickly seed the entire planet. - It might be
29:01
that you will never,
29:01
ever get the initial polymorph again. - After five months of research,
29:06
Abbott's researchers held a press conference to share their findings. (intense music) - "Good afternoon.
29:11
My colleagues and I are here today to explain what has happened,
29:15
why it has happened, how we've responded to the problem,
29:18
and what we're going to do to correct the problem.
29:21
Sometime during this summer,
29:22
the semi-solid formulation of ritonavir began to change into a crystal form,
29:28
a transformation that we believed was a scientific
29:30
and chemical impossibility. - "You are a large multinational company.
29:41
Your scientists are obviously smart.
29:44
How could this happen?" - "A company's size
29:47
and the collective IQs of their scientists have no relationship to this problem.
29:52
This phenomenon is, I believe, unpredictable.
29:54
We are, in some sense, the victim of bad luck.
29:58
There are many mysteries of nature that we've not solved.
30:01
Hurricanes, for example, continue to occur and often cause massive devastation.
30:05
There is nothing that we can do today to prevent a hurricane from striking
30:08
any community or polymorphism from striking any drug.
30:13
Science cannot provide a solution to all our problems." (curious music) - Now,
30:20
here's a good question.
30:21
Is everything polymorphic?
30:24
So nobody had discovered a polymorph of aspirin, right?
30:28
So it had been around, it's one of the earliest drugs.
30:31
It had been crystallized in industry for what, 130, 140 years?
30:38
And so can you say, "Because nobody had discovered a polymorph of aspirin, therefore..."
30:43
No.
30:43
Right?
30:44
The only problem is I discovered Form II of aspirin. (laughs) By accident.
30:51
Right? - It turns out over half of all compounds are known to be polymorphic,
30:56
and there could be more. - The number of polymorphs is proportional to the
30:59
amount of time and money you spend researching
31:02
that compound. - In fact,
31:04
nowadays we know there are not two forms of ritonavir, but at least five.
31:08
So are new cases of disappearing polymorphs something to worry about? - It's quite,
31:13
quite rare.
31:14
We certainly know a lot more than we did when ritonavir occurred,
31:21
but I wouldn't be surprised to see it happen again. -
31:25
If there's a 1% chance the world's gonna end,
31:28
you're gonna do something about it, right?
31:30
If there's a 1% chance a plane is gonna crash, you're not gonna fly,
31:34
right?
31:36
So, so yeah.
31:37
So we're at that situation where it might only be in
31:42
that order of 1%,
31:44
but if it happens,
31:45
it's gonna cost you a hell of a lot more than a few weeks
31:48
of research on polymorphs.
31:50
Ritonavir was one of the red flags
31:54
that caused a lot of regulatory activity
31:58
and a lot of scientific activity around polymorphs. - Nowadays,
32:02
pharmaceutical companies can spend hundreds of thousands to millions of dollars screening for polymorphs.
32:08
In the end, there was no way of getting Form I ritonavir back successfully.
32:12
There were attempts, but all were incredibly costly, and they risked being infected again.
32:19
So instead, Abbott went back to an older liquid formulation of the drug
32:23
and abandoned Form I entirely. - "Our initial activities were directed towards eliminating Form
32:29
II from our environment.
32:30
We finally accepted that we could not.
32:33
Our subsequent activities were directed towards figuring out how to live in a Form
32:38
II world.
32:39
Nature would appear to favor it." (curious music) - The liquid formulation was not ideal.
32:46
It had worse side effects, and not all patients could tolerate it well,
32:50
but it worked. - "It is frightening
32:52
that this could happen to any drug
32:53
that we've taken and on
32:54
which we're dependent,
32:55
even though it is not that common.
32:57
This time, it has happened to Abbott
32:59
and to the tens of thousands of people taking the semi-solid capsule.
33:03
Thankfully, we had the liquid formulation as a safety net.
33:06
Next time it may happen to another drug
33:08
that may not have the safety net." (curious music continues)
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