Chemistry World Podcast - October 2006
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Chemistry World Podcast.
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Chemistry World podcast from the Royal Society of Chemistry with me Chris Smith, Victoria Gill...
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Interviewee - Mark Peplow
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Fusion power: Science Facts or Science Fiction.
Interviewee - Chris Llewellyn Smith
The question is whether we can get it to work reliably in a way that will be economical.
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Interviewee - Lisa Melton
Nicotine is probably one of the only compounds that can suppress that inflammation.
Interviewer - Chris Melton
Interviewee - Roy Lowry
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First though, what do you think of this Chemical Conundrum, which has been sent in by John Cannell?
Interviewee - John Cannell
The repair was a success, but when I put the plate through the dishwasher, the glue line and some previously invisibly smears and fingerprints became bright blue. Can anyone tell me the likely chemistry of my blue pigment please?
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In the meantime, it looks like it could be about to become a whole lot more difficult for athletes to mix drugs in sport, Victoria.
Interviewee - Victoria Gill
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Interviewee - Victoria Gill
Now nandrolone occurs naturally in the body and it builds muscle and bone naturally. So, the difficulty with testing for norandrosterone is that you have to be able to tell the difference between synthetic norandrosterone that's been taken to performance enhance and the naturally occurring norandrosterone. So, this norandrosterone contains carbon and it contains two different types of carbon, two different isotopes, carbon-12 and carbon-13, which has a very slightly different atomic mass. So, what this team have done is, developed a way to measure this mass, so that you can tell the difference between carbon-12 and carbon -13, now the important thing here is that the synthetic version of norandrosterone has slightly more carbon-13 relative to, at the levels of carbon-12 that it has compared to, the naturally occurring norandrosterone.
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Interviewee - Victoria Gill
We don't just eat soy, we eat lots of different plants and meat and so the carbon that we get in naturally occurring, norandrosterone has a much more equal ratio of carbon-12 and carbon-13.
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Interviewee - Mark Peplow
Clearly, they've just done this for norandrosterone, but at the moment they're trying to extend the technique to discover the origins of other drugs by looking at different isotope ratios for example, hydrogen, with its heavy isotope, deuterium, so it's potential to use this mechanism, this technique, to actually look for other drugs. Interestingly, when we spoke to Tony Moffat, who is head of the Centre for Pharmaceutical Analysis at the University of London, he is very involved in drug testing in the UK. He thought this was a really excellent method and a whole lot of promise in it.
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Interviewee - Bea Perks
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Interviewee - Bea Perks
Not only could you do that, you are also learning a lot more about how nerve cells communicate with one another. They've developed these transistor nanowires, silicon nanowires that can resist corrosion, you can grow them along with your cultured neurons for up to a week or just over a week, they've patterned the bottom of cultured dishes with polylysine films along which the neurons will grow, so they can get their neurons to grow exactly where they want them to where the transistors are and so very very specifically they can really look at, yeah, not just what one neuron is doing, but what one extension on one neuron is doing and they really weren't expecting to get quite such precise results as they have done. It's very early days certainly for being able to use this technology in anyway, but the promise for what you will be able to do with this information is incredible and researchers are really amazed by this.
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Will you be able to be put it into the brain and the body would tolerate it or is it just an in vitro technique?
Interviewee - Bea Perks
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Now as the issue of climate change and cleaner energy supplies remains a serious thorn in the sides of politicians internationally, this month Chemistry World caught up with Professor Sir Chris Llewellyn Smith, who is the director of the UK Atomic Energy Authority's Culham Division. He also chairs the body that advices the EU on fusion and he is involved in developing ETA, which is an international project to build a working energy-yielding fusion reactor over the next 10 years. I asked him whether fusion really does have the power to deliver.
Interviewee - Chris Llewellyn Smith
The question is whether we can get it to work reliably in a way that will be economical and I am pretty sure from the experience we have that the big world project will work. The question is if we can make it reliable and economical. Can't be certain, but we are talking about developing options and in a world where we desperately need new large scale sustainable clean energy sources, any sort of option is worth it.
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Interviewee - Chris Llewellyn Smith
That current creates part of the magnetic field you need for reasons I'll explain in a moment, and this also heats the gas. You put in heat also by other means. You get it up to 100 million degrees, something like that. You need the magnetic field to keep it away from the walls. The gas is very dilute, if it touches the wall it will cool down and the reaction will be extinguished, so that you have to have fantastically good insulation. At that temperatures, the deuterium and tritium fuse, they produce helium and a neutron. The neutron being neutral escapes the magnetic field into the wall. It is very energetic, it is stopped, it heats up the wall and the heat is taken out to drive turbines in the usual way. In the wall, the neutron does something else. It encounters lithium and there is a reaction in which neutron plus lithium produces tritium, which is one of the fuels. So the rows of fuels of fusion are lithium from which in the reaction we manufacture tritium and water from which we extract deuterium.
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Interviewee - Chris Llewellyn Smith
First of all, you produce neutrons and the neutrons do activate the wall. By choosing the materials carefully in the wall, one can arrange that the half-lives of the radioactive substances that are created are only about 10 years. With the result that every 10 years the radioactivity is halving, after 100 years you could recycle it. So the walls are radioactive, but it's a problem for your children, your grandchildren may be, but not for hundreds of thousands of years, whereas in a normal nuclear reactor, you've got the core as well as the walls and that's where the real problem is. The other reason is that the fuels, lithium and water, are highly abundant and there is enough fuels out there for millions of years probably, and that's certainly not the case with uranium.
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Interviewee - Chris Llewellyn Smith
In fusion, it's continuously fuelled. There is only enough fuel in that for about 30 seconds. So if anything goes wrong, it will just go out and in fact anything at all goes wrong creating the conditions is so delicate, the slightest perturbation -- it is going to stop. So it is self-limiting, absolutely automatically; there is no run away reaction, nothing like that.
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Interviewee - Chris Llewellyn Smith
That project -- the goal is to produce at least 500 megawatts with about 50 million watts of heating power, now that's not really why what you want it completely, because the fusion power isn't electrical power. When you turn it to electrical power you would lose something and the heating power is 15 megawatts, but you need more than that, you know, out of the system to heat it. Nevertheless, it will be producing more power out than in and if that works, it's going to be proof of principle. We'll then build a slightly bigger system with turbines and so on. Now the time scale for all this -- it will be running in about 10 years. If the results are favourable, we'll then be ready to build a real power station with turbines and actually putting electricity into the grid.
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Now fusion offers the possibility of the green energy supply, but earlier this year, scientists rocked the world when they said, plants make greenhouse gases, Mark!
Interviewee - Mark Peplow
It took a lot of people by surprise. We normally think of plants as inhaling carbon dioxide and exhaling oxygen and thus they are taking in carbon dioxide, this greenhouse gas, which is obviously one of things that is responsible for global warming, as its concentration in the atmosphere increases. Now this paper, when it was published in January, created a lot of controversy. Nobody expected plants to make methane and in fact, the quantities -- the sheer quantities of methane that they were putting out were shocking and the researchers that found this, led by Frank Keppler of the Max Plank Institute in Heidelberg in Germany, sort of, scaled up from their laboratory experiments to work out how much methane all the plants in the world will likely to be putting out and it was loads; upper limit was 236,000,000 tons a year, that's a substantial proportion of all the methane going into the atmosphere.
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Interviewee - Mark Peplow
The key thing is they had sort of just done that scale up assuming that all of the metabolically active part of a plant would emit methane at the same rate. The truth is that's not true. The woody parts or the dark parts, the bits of the plant that aren't exposed to light, aren't necessarily going to produce the same amount of methane. So what Keppler has actually done is collaborate with a guy called Sander Houweling at the Netherlands Institute for Space Research in Utrecht, to try and approach this problem from the top down if you like, previously they looked at one or two plants and scaled up to the whole world. What they've now done is added data from satellite measurements of methane concentrations in the atmosphere and they've revised their estimate by about a half, the upper limit now they are saying is about 125 million tons a year coming from plants. Now this doesn't go against the initial observation that plants can produce methane, which is surprising enough in itself. But what it does do is perhaps work against some of the arguments, which we've seen over the last year about how much plants might actually be contributing to the global methane budget and thus contributing to global warming.
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Interviewee - Bea Perks
So there is always a difficult thing, this field of looking for ways to treat malaria, because it's obviously a huge problem and you don't want to really raise expectations too soon. But David Peyton at Portland State University in Oregon has taken one new route to this, resistance to malaria drugs has grown numb to the point where drug resistance becomes such a problem that some of the most successful malaria drugs that are just useless now, but there is suddenly quite a lot known about the resistance and there is a molecular strategy to reverse that resistance and what David Peyton has done is he has connected the molecule linked to resistance to the actual chloroquine drug, the chloroquine malaria drug and so what you can do this way is reverse the resistance and get the drug in at the same time and the reason he is really excited about this is because chloroquine is a fantastic drug or was a particularly fantastic drug for treating newborn babies and pregnant mothers.
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Interviewee - Bea Perks
So, far it has really looked very good, but we were talking to somebody from the World Health Organization's Roll Back Malaria Campaign and he was saying it looks great, but there were so many drugs that get to this stage with really quite successful looking results and the by time it's gone through the trials, well we just have to wait and watch.
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Interviewee - Bea Perks
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And now to nicotine, a drug which is much maligned in the medical world, but as Novartis foundation Science writer, Lisa Melton has been finding out, this one cloud of smoke may actually have a silver lining.
Interviewee - Lisa Melton
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Interviewee - Lisa Melton
Chris Smith
Interviewee - Lisa Melton
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Interviewee - Lisa Melton
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Interviewee - Lisa Melton
I think, that the scientist who was looking at this, Luis Ulloa, he is based in New York. He was looking into Alzheimer's disease and what types of compounds might stop the inflammation and the neurodegeneration in Alzheimer's. But really his interest is in sepsis, and sepsis is probably one of the most lethal inflammatory conditions. In fact, it's caused by bacteria and even though they can't control the infection with antibiotics, it's the inflammation that actually kills the person and what he has found is that nicotine is probably one of the only compound that can suppress that inflammation.
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Interviewee - Lisa Melton
What he has found is that nicotine mimics one of the body's own anti-inflammatory agents. This anti-inflammatory agent in itself is quite interesting because it's acetylcholine; nerve cells produce it when they sense that there is an inflammation and then acetylcholine tells the macrophages, which are immune cells, well, now you go off and produce lots of cytokines and these are the ones that whip up all the symptoms that we know of inflammation, like fever and heat.
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Interviewee - Lisa Melton
So it's odd to think that there is a compound in tobacco that is doing the same thing, as the body's own chemicals, but much better.
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Interviewee - Lisa Melton
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Interviewee - Lisa Melton
As a matter of fact, it was a bit of a lucky stroke, because they had been a few nicotine-like drugs that were developed for Alzheimer's disease. They didn't work for Alzheimer's and Luis Ulloa and other scientists, believed that that might be because they are not getting into the brain, so he is working with these drugs to see whether they could be used as anti-inflammatory.
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Now on the subjects of nicotine, here's a subject that's really smoking, Bacteria powered motors, Bea what's this all about.
Interviewee - Bea Perks
Well Yuichi Hiratsuka and colleagues in Japan have used motile bacteria to rotate a microscopic motor and they say it's the first micromechanical device to integrate inorganic materials in living bacteria. They have put bacteria into a circular channel and on top of the circular channel, they've placed a rotor with a little tiny bits that stick out from the bottom of the rotor, so as the bacteria go round in the rotor, they take the rotor with them and nobody quite knows actually how these bacteria work, but they certainly, once you put them into these channel, they all seem to go round in the same direction conveniently.
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Interviewee - Bea Perks
They thought it would look like there was little army of bacteria marching along below, but it really moved smoothly and yeah, they are thinking what could we use this for, but of course, I mean, they've really have only just developed this and not about to start to using it for anything useful.
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I mean, has anyone tried to measure the torque on this one.
Interviewee - Bea Perks
They're thinking perhaps they could use it for safer, micro and nanofluidic devices, where you really have very tiny, tiny volumes that you want to pass along different channels.
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Because that will be more useful wouldn't it?
Interviewee - Bea Perks
They are feeding them certainly glucose at the moment, but now may be better speed in there or something, get them really whizzing around.
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Now what about this subject of waterproof paper, Victoria.
Interviewee - Victoria Gill
So they've grafted atoms, glycidyl methacrylate atoms onto the cellulose fibers and this glycidyl methacrylate is a sort of, a molecular glue, so onto that they can then graft additional molecules, so they've grafted on little brush like molecules with fluorine atoms on them and the fluorine atoms are very hydrophobic, so the paper is then completely waterproof.
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Interviewee - Victoria Gill
I think its sort of a, it's a very cheap, very renewable way to make these layers that have certain functions, so if you want very cheap way to make a waterproof membrane for something, then this would be useful, but also it doesn't necessarily have to be fluorine atoms that they graft on here, it could be something else, so it could be a chemical sensor or something. So you could use it as a chemical sensor made of paper, which would be very renewable and very green.
Interviewee - Mark Peplow
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Because the paper won't be particularly heavy and this means you could make things a lot lighter.
Interviewee - Mark Peplow
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Interviewee - Victoria Gill
I don't think, but they are pretty excited about the fact that this cellulose fibers, the paper is so cheap in abundance and biodegradable that it could be applied for lots of different things as Mark was saying it's not just for writing on.
Interviewee - Chris Smith
Roy Lowry is a senior lecturer in Physical Chemistry at the University of Plymouth. On August of 16th this year, he potentially blasted his way into the record books by detonating more fireworks in 30 seconds than anyone had managed before. And it was all in the name of sexing up chemistry.
Interviewee - Roy Lowry
At the end of the day, we actually only had 4 left in the frame but due to Guinness Records I think we currently claim a new record of fifty six thousand five hundred and four.
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Interviewee - Roy Lowry
These rockets were packed into frames, which were basically two layers of chicken wire, the rockets are on the top layer and the bottom layer simply helped to stick the sickles. Now we laced into the top layer of chicken wire, was something called quickmatch; now quickmatch is essentially gunpowder in a tube and the flame inside that travels around about 25 meters a second hence its name quickmatch. Spread off from that were various strands of something called blackmatch; now blackmatch is, it burns a little bit slower, but it's again gunpowder coated on the outside of string in this case and that formed a matrix onto which we sat all of the rockets, now each frame had three little bits of quickmatch in it, these were ignited electrically from around 100 meters away with the button.
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Interviewee - Roy Lowry
My career up to now has been in two halves really. Half of it was as a scientist, a chemist, as a lecturer at the University of Plymouth and the other half was as stage lighting technician. Now if you go into that sort of business with a degree in chemistry you bound to end up doing the stage power techniques.
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Interviewee - Roy Lowry
You know that once they are in the air, there's going to be midair collision and therefore quite a lot of them are going to spray out and start firing horizontally. The one thing we didn't take account of and I should have done is the fact that an ordinary rocket just sat there in your back garden lifting up from the milk bottle, there is a lot of heat dissipation out the side wall of the cardboard too. That can't happen if you got thousands of these things packed in together and consequently these ignition temperature was a lot higher and consequently they flew 3 or 400 meters and in fact they should have only flown about 100.
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Interviewee - Roy Lowry
So it's that first 3 or 4 seconds of burn that's really important and of course it was that that would be heated up by all those other rockets in close proximity, so these things will go in three or four times their correct distance really.
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But did you get any criticism from people saying actually this is a bit wasteful or this isn't really achieving much in the way of helping chemistry.
Interviewee - Roy Lowry
Now I should point out that the rockets were donated to us and they were due for disposal anyway. Now the alternative would be to soak the rockets in water to remove the nitrates, which is an important part of the gunpowder and nitrates in water is completely bad news, then you would take all the cardboard basically the charcoal from the gunpowder that is left over, put them into land fills and let them stew up to be methane, which will cause a much worse greenhouse gas than carbon dioxide, so in fact we were disposing them in a very environmentally friendly way.
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Doesn't it involve a number heavy metals in that?
Interviewee - Roy Lowry
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Interviewee - Roy Lowry
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Interviewee - Roy Lowry
Long term, well there is another possibility of another project but these things take a while to generate, so I'll just leave it at that for the time being, if you don't mind.
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Now August also saw Europe's very first Chemistry Congress take place in Hungary. Mark, you went along, what was it like?
Interviewee - Mark Peplow
One of the great bits of this job is that I get to go to reasonably exotic places, to go to conferences and this was an important one, it really was a milestone. It is the first conference organized by the European Association for Chemical and Molecular Sciences and it's the first time that they brought together, sort of pan-European chemistry conference. There were about 3000 chemists there and it was excellent. One of the most interesting things that I saw was a talk by a guy called Koni Grob. He's the head of the official Food Control Authority in Zurich and he was talking about the sort of chemicals that can leach from food packaging into the food that we eat. He's finding almost all the samples that they tested, breached EU levels on that.
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Interviewee - Mark Peplow
One of the chemicals that he investigated was something called epoxidised soy bean oil. Basically that's something that they put into plastic lids on food jars to make the plastic more flexible, so it makes a good sale. Now this epoxidised soybean oil itself isn't toxic, there's no problem with that, so people shouldn't worry about that, but what they found was that there was a substantial amount of this stuff coming through into particularly oily foods.
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Interviewee - Mark Peplow
Now the crucial thing to remember is, Koni Grob isn't trying to start to food scare because like we said we don't know the identity of most of these leached compounds, but what he says is, that it's a very important issue that's actually being overlooked by most food analysis agencies across Europe and a lot more work needs to be done to actually identify what these things are.
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Interviewee - Mark Peplow
Over time, these things can break down into smaller fragments. There is really no way to the moment that you can tell exactly what all these things are. This is Grob's point really that you really need to look at what they are.
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Interviewee - Mark Peplow
There were about 12 or 13,000 people registered for the conference at the start; this was in San Francisco, I want to say, but by the end of it, estimates were ranging up to 16 even 17,000 people. One of the interesting things about that, it makes the conference rather unwieldy if you like, to get around and compared with the Budapest meeting, much smaller about 3,000 people, it made a lot more difficult for scientists from different disciplines, to actually get together to discuss those big multidisciplinary problems that chemistry really is in a good position to solve.
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Interviewee - Mark Peplow
What she's been doing is inventing molecules that can interrupt the chemical conversations that go on between bacteria. One of the major problems with bacteria is that when they get into your body, just a few of them, you can beat with antibiotics, but when they team up together, they start collaborating to make this protective biofilm made out of polysaccharides, now once they have got that shield over them, it's incredibly difficult to actually get the antibiotics through to them. So they can really take hold within a patient's system.
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Interviewee - Mark Peplow
They can stop the bacteria collaborating. What they've done is actually taken some of these signalling molecules a type of compounds called Lactones that are used by gram-negative bacteria and they've altered them slightly and this interrupts the conversations, it stops the bacteria talking to each other which stops them forming a biofilm, which makes them more vulnerable to then furring in some antibiotics.
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Do we know these molecules are safe?
Interviewee - Mark Peplow
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Interviewee - Mark Peplow
Basically the key thing about these compounds is that they are very cheap and easy to make. So if there is success in clinical trials, this might be a useful combination therapy, if you like, or even a pre-emptive thing that if you know people are going to be susceptible to these infections, you give them some of these conversation stopper molecules beforehand and that stops the bacteria taking a hold.
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Chemistry World blog, which is at chemistry world dot org forward slash blog. Now if you cast your mind back to the start of the show I mentioned John's question about his mended plate turning blue in the dishwasher.
Interviewee - John Cannell
The repair was a success, but when I put the plate through the dishwasher, the glue line and some previously invisible smears and fingerprints became bright blue. Can anyone tell me the likely chemistry of my blue pigment please?
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Interviewee - Colin Cook
Now this test was used to detect the concentration of ammonia in aqueous solution and we added sodium phenate which is a solution of phenol in sodium hydroxide plus sodium hypochlorite, which is a kind of bleach, to create the blue colour. Now current epoxy glues use an epoxy resin and an amine hardener; now an amine is just a type of ammonia and in the environment of the dishwasher, there is a highly alkaline environment plus the addition of a chlorinated organic compound used as a bleach and I believe that the residues from the epoxy and the amine react together in this environment to produce the blue colour.
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That was Colin Cook. Now can you help with this month's Chemical Conundrum, which has been sent in by Monica Wilde.
Interviewee - Monica Wilde
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The show was produced by me, Chris Smith from the naked scientists dot com and also featured Chemistry World Editor, Mark Peplow, Deputy Editor, Bea Perks, and Chemistry World Science correspondent Victoria Gill. Until next time, Good bye!
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