December
Chemistry World Podcast - December 2007
INTRODUCTION
(Promo)
Brought to you by the Royal Society of Chemistry, this is the Chemistry World Podcast.
(Promo ends)
Interviewer - Chris Smith
Hello, welcome to the Chemistry World Podcast, which is brought to you this month by Mark Peplow, Victoria Gill, Ananyo Bhattacharya, and Richard Van Noorden. I am Chris Smith. Coming up, why we won't be pouring energy down the drain in future.
Interviewee -- Mark Peplow
Just imagine if you could run your car based on the stuff that you flush down the toilet every day.
Interviewer - Chris Smith
Drugs and condoms.
Interviewee -- Mark Peplow
Maybe you flushed down in your toilet, Chris. I am talking about getting fuel from sewage waste.
Interviewer - Chris Smith
A Car driven by sewage, not something you want to get stuck behind on a hot day. Also, we meet the inventor of oral contraceptive chemistry to hear how he has branched out into writing books, plays, and believe it or not, rap music and he is not that bad either.
Rap Music
Interviewer - Chris Smith
The rapping chemist, Carl Djerassi, he is coming up shortly. Plus, we explore the golden age of home experimentation and a Nobel Prize winner recalls what he did with his first chemistry set.
Interviewee -- Kary Mullis
I ended up eventually making rather large, you know, four-foot-tall rockets and sending little frogs up two miles in the air using that same chemistry and it was a tremendous learning experience then because we didn't have a book that told us exactly how to do that.
Interviewer - Chris Smith
So, that really was a giant leap, at least where the frogs were concerned. There is more from Kary Mullis coming up later in the program, when we will also solving last month's colourful chemical conundrum.
Interviewee - Ron Lancaster
Every year my local fireworks display. I always see there are so many colours being sprayed out into the sky. Are there any colours of fireworks that can't be made?
Interviewer - Chris Smith
No idea. Well, keep listening to find out because the answer certainly had me surprised.
(Promo)
The Chemistry World Podcast is brought to you by the Royal Society of Chemistry. Look us up online at Chemistry World dot org.
(Promo ends)
Interviewer - Chris Smith
Now, they say that one man's trash is another man's treasure and a recent breakthrough suggests that we might be able to power cars with what currently goes down the drain, Mark.
Interviewee -- Mark Peplow
Yeah, that's right, Chris. Just imagine if you could run your car based on the stuff that you flush down the toilet every day.
Interviewer - Chris Smith
Drugs and condoms.
Interviewee -- Mark Peplow
Maybe you flushed down in your toilet, Chris. I am talking about getting fuel from sewage waste. There's been a lot of talk over the last few years about the hydrogen economy, the idea that we can run our cars on hydrogen gas and that's fantastic, you combine hydrogen and oxygen in a fuel cell in a car and that creates an electrical current that you use to drive the car and the only waste product is water and what could be cleaner. Well, the problem is where do you get the hydrogen from in the first place and any viable large scale ways of doing that at the moment are either starting with fossil fuels in the first place, which we all are trying to avoid or indeed splitting water by using vast amounts of electricity and again to get those vast amounts of electricity you really need a sustainable source.
Interviewer - Chris Smith
So, what have they done instead?
Interviewee -- Mark Peplow
Chemists have been looking for alternative ways of getting that hydrogen and the latest development is by Bruce Logan who is based at Penn State University in the States. Effectively what he has done is, he has taken that fuel cell that you find in a hydrogen-powered car and reverse engineered it. What it means is that he uses some friendly bacteria to chump up the molecules that you find in sewage waste and turn them into charged hydrogen atoms. Now, this is all done on one electrode if you like in a two-electrode fuel cell. Those hydrogen ions move across the cell to the other electrode where they combine to make hydrogen gas on a platinum electrode. Now, it takes a little bit of additional electricity to help them do this, but in fact once you do all the sums what you are effectively doing is getting out three times as much energy as you are actually putting in and remember the source for this is all waste, anyway it's all sewage waste.
Interviewer - Chris Smith
Is it scaleable though, Mark?
Interviewee -- Mark Peplow
Loganthinks that this particular system, they can scale because his team has been more concerned with getting the efficiency right rather than the speed right. Previous researchers have often been looking at having these things that will actually go into pipes so that they can take hydrogen if you like from flowing sewage. He sacrificed a bit in terms of the speed that this can work out in terms of actually being able to make sure it works efficiently.
Interviewer - Chris Smith
So, how much energy can you get out of one of these cells?
Interviewee -- Mark Peplow
Well, it very much depends on how much feeds that you can put into it, how much sewage you can put into it. What he is talking about, he is imagining a situation where you could have these units cited at sewage plants. So, you are dealing with a very large, but very slow moving volume. So, given enough time, this really can create quite a lot of hydrogen to store it up if you like.
Interviewer - Chris Smith
Then, I suppose it creates another problem, which is you then got to distribute that hydrogen; whereas, if you have got a small portable unit. I suppose it swings us roundabout; otherwise, you are going to cart around sewage with which you rather cart around.
Interviewee -- Mark Peplow
This is interesting. This eternal argument about the hydrogen economy, exactly how you implement and yeah, my point of view on this is that developing the infrastructure for this and completely replacing a petroleum-based infrastructure is completely unrealistic. You are better off with having specific uses for hydrogen, for instance, fleets of buses, municipal transports, all those vehicles that do a small amount of driving every day and return to a depot every day, because if they are all returning to one depot, then they can all be refilled by just a single filling station that covers a whole region rather than having to cater for thousands of motorists that want the convenience of a gas station on every corner.
Interviewer - Chris Smith
It still sounds like a brilliant idea turning something, which does literally go down the drain into useful energy, but now sticking with things, which are very small, we have talked about bacteria, now diving down to the level of the individual gene and silencing them, Victoria.
Interviewee -- Victoria Gill
Yep, this work comes out of North-Western University in US and Chad Mirkin there has created tiny gold nanoparticles with small strands of DNA attached that can target specific genes and switch them off, and he had shown this previously, but what he has done now is attach additional molecules to these DNA strands that cause tiny little nano-flares that show the process happening. So, you can watch gene silencing in real-time.
Interviewer - Chris Smith
How is this better than say RNA interference, because it sounds like it's very similar. You put a piece of nucleic acid and it binds to the mirror image signal already in the cell and inactivates it.
Interviewee -- Victoria Gill
Yeah, it is very similar. It is gene silencing. So, selectively silencing a gene that you want to switch off, but the crucial thing about this is that you have a vehicle for the gene silencing operator. So, your little stranded DNA that binds to your RNA that you want to then switch off your gene is your nanoparticle and the gold nanoparticle can get inside the cell. It doesn't have to be microinjected or introduced in any other way. It can just travel into the cell.
Interviewer - Chris Smith
So, this might be the sort of therapeutic thing everyone has been looking for, how do you get these therapeutic nucleic acids into cells in the first place, especially say cancers to shut off genes that we know are associated with disease.
Interviewee -- Victoria Gill
Yes. So, this is the next step. At the moment, these gold nanoparticles will travel into any cell that you introduce them to, but introducing some kind of selectivity to that will be the next step so that you can choose that these nanoparticles will be able to switch off genes specifically inside cancer cells for example, as you say.
Interviewer - Chris Smith
And one of the interesting things you mentioned was being able to actually physically see the process happening, why do they think that will be useful then?
Interviewee -- Victoria Gill
Well, that's diagnostically useful. So, for example, if you can use this for therapies, you can then see your therapy working in real-time and you can see your genes being switched off and you can also see the level of the gene that's being produced in the cell.
Interviewer - Chris Smith
Alright, is it quantitative?
Interviewee -- Victoria Gill
Yes, it is. The number of molecules that cause these flares are actually directly related to the amount of gene that is being produced. So, it is measurable.
Interviewer - Chris Smith
What sorts of targets have they looked at so far with this, has it just been proof of principle or are they actually looking at a whole raft of genes? Does it work across the border, I guess is what I am asking?
Interviewee -- Victoria Gill
At the moment, it's just proof of principle. In theory, it will work in any gene that you target, but at the moment they are just showing that they can display it, they can produce these little nano flares and they can switch off these genes and they have measured that, but yeah, it's just proof of principle at this stage.
Interviewer - Chris Smith
Thanks Victoria. Now, from nano flares to someone with a big flair for creative writing and that includes books, plays, and even rap songs. It's Carl Djerassi. He is the chemist who has helped to create the oral contraceptive pill, but in recent years, his mission has been to bring people a bit closer to science as he explained to Meera Senthilingam when they met up in London earlier this month.
Rap Music
Interviewer - Meera Senthilingam
This month, world renowned chemist, Professor Carl Djerassi gave a talk at the Royal Society in London. Now, Carl is quite a legend as he was the creator of the first steroidal contraceptive pill, but he has retired from the world of chemistry now and mastered the profession of play writing, occasionally even using rap as a medium to communicate science. His event in London was titled 'Washing Dirty Lab Coats in Public'. So, I met up with him to find out what exactly he was trying to portray in his talk.
Interviewee -- Carl Djerassi
When one talks to the general public about science, one usually talks about the science that is being done, the discoveries or inventions. I wanted to talk about the behaviour and culture of scientists, which is totally unknown really to the general public or else exaggerated Frankensteins or nerds and I am going to show that boring human beings with all of our qualities as well as foibles and I tried to illustrate this both in my novels which I call science-in-fiction and in my theatre plays which I call science-in-theatre.
Interviewer - Meera Senthilingam
Which you say you are trying to get people to see the actual darker sides because there is not enough of that shown in the public as it is or are you trying to just show the culture as a whole, so both the positives and the darker sides?
Interviewee -- Carl Djerassi
Oh, absolutely the latter, I confirm that culture and I cannot shed it. I think it is both, the most cooperative of early human endeavours and the most brutally competitive at the same time. That is the unusual thing. It is important that people realize this and I think the unrealistic thing is you know to put scientists on their pedestals, the other thing is, you know, since I am talking to a woman, it is one of the evolving issues in every one of my plays and novels there were all of modern women in a male-dominated discipline. The very phallocentric nature of science, which is not unexpected because it was created exclusively by men, who established the rules of the game. Now that women get into the field also as professors and chairs of departments so, I am writing about this. I am writing about their barriers and so on.
Interviewer - Meera Senthilingam
It's interesting that you talk about the role of women in the world of science. Some of your earlier discoveries had an effect on the place of women in society to begin with. You obviously were one of the inventors of the first steroidal contraceptive pill. Is that something that has resulted from things like the pill?
Interviewee -- Carl Djerassi
I was involved in the first chemical synthesis of oral contraception. I am a chemist. So, that we did in 1951, norethindrone, the first oral contraceptive to be synthesized, the recognition or the impact that oral contraceptives would have on women everywhere in the world, I think one would be lying if one said all these people realized all that in the 1950s, because no one expected women would have accepted that quickly and on that huge scale and the implications which also happened, people forget this. The 1960s, people say that the Pill caused the sexual revolution. In the 1960s, was then the decade of rock and roll music, the hippie culture, the drug culture, most importantly the women's liberation movement which really moved the middle and late 1960s, particularly in the States. It was that mixture, remember the chemical work was done in 1951, the approval in United States only came in 1960, came at exactly the right time.
Interviewer - Meera Senthilingam
Are you quite proud of what has happened as a result of you creating such a steroid?
Interviewee -- Carl Djerassi
Absolutely. If you ask me, I could do it all over again. I would do it now, the answer is yes.
Interviewer - Meera Senthilingam
You had a very flourishing career as a chemist, what made you want to start writing and start wanting to do plays, to show the culture of science today?
Interviewee -- Carl Djerassi
It was a very logical transition, because soon after work on the pill, there was lot of lecturing and teaching, as director of research in this area for a number of years and I realized there where I was talking about the cultural, psychological, economic, legal aspects, which are much more complex and I decided to become an intellectual smuggler, really smuggle information that people either don't want to hear or they are afraid of it, and opportunity for this in the guise of fiction and this is why I call it science-in-fiction rather than science fiction, but I did it with an interesting story that people would continue to read and turn the pages, but when they actually did get to the last page they had learnt something whether they realized it or not.
Rap Music
Interviewer - Meera Senthilingam
You said you use things like a rap in order to help get some of your information across. How well have those been received?
Interviewee -- Carl Djerassi
Well, that went fantastically well. These two raps that I commissioned I didn't do them nor did I sing them. I commissioned for Oxygen and for NO and I have written this well, for instance, I did this rap yesterday one of them, Oxygen, who rapped at the Royal Society. Well, there were not any young people there, but they were all beaming and bouncing. Rap is a very interesting style. Then, if you think about even some of the vicious rap has some interesting pedagogic information transmittal aspect. So, it's a very modern form of music, but ----it's unusual to do it in the content of science. So, I wanted of course to do the unusual thing so people get interested and at the same time absorb some information.
Interviewer - Meera Senthilingam
What part of your career would you say you have enjoyed the most, the part as a chemist or the part as a novelist/play write?
Interviewee -- Carl Djerassi
What I am doing now is writing plays, writing novels again some non fiction in dialogue form and giving lots of lectures, particularly in Europe. So, I enjoy that most, no question. One of the reasons of course because you are entirely, totally, 100% involved in this without any infrastructure and you know as a scientist, there is a team, you have to write grant applications and if you do this and that, it's done and if things move on even if you do not do anything. Well now, if I don't write no one else is going to do it for me. So, I enjoy that most.
Interviewer - Meera Senthilingam
Even if anyone else did do it for him, I don't think they do it as well. Carl has now written over 10 plays and even more novels, which have all had success worldwide in portraying the culture of science. I leave you with another insert of his modern method of chemistry education.
Rap Music
Interviewer - Chris Smith
Carl Djerassi talking to Meera Senthilingam about his plays, books, and raps. On the way, the sweet taste of success, as researchers uncover the origins of chocolate consumption and the world's smallest microwave oven. It's tinier than a pin head. So, even by ready-meal standards it wouldn't cook much. So, what's it for. Well, before we find out to something that most men have got many of whom probably played with a great deal when they were little, but they turned to have lost interest in as times gone by. I am of course talking about chemistry sets, which these days are being universally received as not as good as they used to be. Indeed in his latest book Bill Bryson tells of his disappointment on performing his first experiment and is anticipating at least a modest mushroom cloud, but being greeted instead by rather undramatic colour change. But what's the history of home experimentation and what's its future? I caught up with the Chemical Heritage Foundation's Rosie Divernieri to find out.
Interviewee -- Rosie Divernieri
The first "chemistry set" that I have seen reference in a book is actually in 1791. They are referred to as portable chests of chemistry and they were mainly geared toward university students. These are people who study natural philosophy; people studying agriculture, metallurgy, things along those lines.
Interviewer - Chris Smith
But this is a bit like a student having their own dissection kit for doing their anatomy classes is not the same thing as say me having a chemistry set to play with, with my children. So, when did that sort of chemistry come in?
Interviewee -- Rosie Divernieri
The first company in the US was actually the Porter Chemical Company, who manufactured the Chemcraft chemistry set and 1912-1916 is roughly around the time that we see Chemcraft come out with its first non-expertise chemistry set. The Chemcraft sets were first introduced in United States department stores and they were very frequently put in the toy department.
Interviewer - Chris Smith
So, what sort of things could you do with your chemistry sets, say you bought one in 1915, what sort of things could you do with it?
Interviewee -- Rosie Divernieri
If you bought a set in 1915, it was very similar to the experiments that you see all through the 19th century, you know, making compounds, making mixtures, making things change colour. There were some experiments that involved using some sort of heat source underneath it. They were fairly simple experiments at that point. It was really meant to be an introduction and to get children interested in science. That changes in the late 1930s, early 1940s when A. C. Gilbert, who was the inventor of the Erector set comes in and that's when you see the experiments start to really take off into the wild and the absurd to blowing things up, to creating you know green piles of goo that you can gross your sister out with.
Interviewer - Chris Smith
It is interesting to say gross your sister out, because even if I wind my mind back to my first chemistry set, it wasn't that long ago, it's got a kid on the front of the box with his sort of shirt and tie on, stereotypical geek and it's a guy, no girls.
Interviewee -- Rosie Divernieri
Right. It's interesting that you mentioned that shirt and tie that is something that you see last up, until the 1960s and 1970s they are all boys, they are all usually young, usually have brown hair and they are all wearing a very nice shirt and tie. They do look like your stereotypical science nerd and they were very much meant for boys. Girls were not encouraged to think of careers in science. Of course, we know that, that did not happen. Women were interested in chemistry sets and chemistry from the very beginning. I have a woman who is now a professor who wanted a chemistry set so badly that she decided to make her own with things she found underneath her mothers sink, cleaning materials, ammonia, bleach, things like that.
Interviewer - Chris Smith
It's interesting that you say people making their own chemistry sets, because I think we are going to see a resurgence of that aren't we, because hasn't the rock set in where the actual excitement you see in chemistry sets has really diminished because I think you have gone on record yourself for saying people are selling chemistry sets these days without actually having any chemicals in them?
Interviewee -- Rosie Divernieri
It's absolutely true. You buy these sets and literally on the boxes they say contains no chemicals and of course to people who grew up with being able to handle hazardous chemicals and getting chemistry sets with that contain uranium dust, how can you have a chemistry set without any chemicals. So, there is a resurgence of what I would like to call underground chemistry sets. People who go out and they buy very small quantities of chemicals. They get one of these old books. They become absolutely fascinated with the experiments in there and then create their own chemistry sets. Buying small quantities of certain chemicals and buying lab glassware is no problem with the invention of the internet now.
Interviewer - Chris Smith
I think, there was a young boy in America who managed to build a fast-breeder reactor in his garden shed by writing of to various laboratory suppliers and then buying all the materials he needed and then got a 100 odd smoke detectors and got the americium out, but the thing that presumably is driving this is an obsession withheld from safety, because companies are worried about supplying chemicals that people might create explosions with and therefore, end up with a lawsuit.
Interviewee -- Rosie Divernieri
Absolutely. The boy you referred to is known here as the radioactive boy scout. He was given a book called the golden book of chemistry experiments, which there is a folk legend that it was banned in the 1960s and then was reissued taking out certain parts of it because you know after someone makes a particle accelerator in their shed, you don't want someone else to be able to learn how to do that. It is very much driven by a focus on health and safety. I like to think it as more of a psychological barrier on the part of consumers as opposed to an actual fear. For a long time, especially in United States, we were inundated with chemicals are bad and then after 9/11 it became even more difficult to buy certain compounds, but if you have enough wear-with-all, you can definitely figure out a way to do it.
Interviewer - Chris Smith
Rosie Divernieri and here's someone who certainly had the wear-with-all when it came to chemistry, because he won the Nobel Prize for discovering the polymerized chain reaction and who would have believed that it all began by firing frogs into low-Earth orbit.
Interviewee -- Kary Mullis
My name is Kary Mullis. I won the Nobel Prize in Chemistry in 1993, which was quite an honour. The first chemistry set I had was a Gilbert chemistry set and it was at a time, that would have been back in the 1950s, when our liability insurance and all that kind of stuff wasn't nearly what it is today and so the makers of chemistry sets could really include a lot of very interesting chemicals. Things that could in fact be turned into what little boys are most interested in it, things that explode or burn really fast, things like that. The literature that came with them they would say don't do this or if you do this do it under very small scale or something like that and it was like daring to do it.
Interviewer - Chris Smith
So, do you think it is a major problem in today's world then Kary, the fact that there isn't this inherent danger; therefore, people learn no respect for things that are dangerous and at the same time they don't have any inclination to want to do anything, because it isn't dangerous?
Interviewee -- Kary Mullis
Well, as far as not learning about the danger, I am sure some people probably got injured with those original chemistry sets, but most people, like me, when they said this would blow up and I took them seriously and I did things on a rather small scale and carefully, at first of all I check it out, what it would do. It certainly takes the thrill out of it that the chemicals that they give you basically are very innocuous things that they change colours. They make plastics out of them. Things like that, but nothing the way you could make your own fireworks or something like that.
Interviewer - Chris Smith
Because as even chemistry sets in the market now, which don't purport to contain any chemicals whatsoever?
Interviewee -- Kary Mullis
I am not surprised. The last time I have looked at one I thought it was quite un-entertaining and innocuous looking.
Interviewer - Chris Smith
It's easy to say though if I hadn't played with this chemistry set, then I probably wouldn't be doing what I do now. Do you think that you could honestly say that though, do you think that you were just interested in science anyway?
Interviewee -- Kary Mullis
I don't think that's true because as a part of the same time when people were not frightened of liability and stuff, when I was in the seventh grade our chemistry teacher would allow us to come into the chemistry lab after school was closed and so, a friend of mine and I, who were interested in chemistry, she let us into the chemistry staff room and let us set up experiments and play with things right there in the high school.
Interviewer - Chris Smith
And, come on, be honest, did this actually result in some dangerous shenanigans getting on?
Interviewee -- Kary Mullis
Well probably, not terribly, but you know you make a mixture of say potassium nitrate and sugar and you heat it up carefully. When it solidifies after it melts, if you light it, it's quite exciting. I ended up eventually making rather large, you know four-foot-tall rockets and sending little frogs up two miles in the air using that same chemistry and it was a tremendous learning experience that because we didn't have a book where that told us exactly how to do that and I just sort of had to figure it out slowly we made little, little ones to start with and bigger and bigger and bigger ones and just had to finally get to a point where we could put a frog in a little film canister so that we can tie that one with a parachute and it was quite an experience.
Interviewer - Chris Smith
Did you get the frog back?
Interviewee -- Kary Mullis
Yes. The frog came back with a little red parachute, 35 mm film used to come in these little aluminium canisters and that was about the size of these little frogs that were always available in my front yard.
Interviewer - Chris Smith
Carrie, how many fingers have you got?
Interviewee -- Kary Mullis
All ten.
Interviewer - Chris Smith
So, you came through the experience unscathed?
Interviewee -- Kary Mullis
You know, we had a couple of explosions, but we never were close enough to the launching pad where you can get hurt. At one time, when I tried to make a two-stage rocket that's what they were doing at Cape Canaveral at the time and so we thought we should try to do and so, that time I almost hit my dad, who was out there. The second stage didn't go off until the thing was already coming back down and so, it went off and angled toward us and my dad kicked it on the fitting, so that kind of freaked us a little bit, but none of us ever got hurt or even burned. One time when I was heating this fuel, it caught on fire in this spot and we were under a tree and it did mess up the tree pretty bad, but we had lots of trees in our yard anyhow.
Interviewer - Chris Smith
If any of that kind of excuse had washed with my mother, then my childhood would have been a lot more comfortable. That was Kary Mullis recalling his first forays into chemistry and I am also comforted to hear that the rocketeering frogs didn't croak in either.
Music
Interviewer - Chris Smith
Now, it's time to take a look at the worldwide web and what it has got in store for chemistry as Richard Van Noorden explained to Meera Senthilingam.
Interviewee - Richard Van Noorden
It's amazing that the internet is really becoming flooded with free chemical information of a really quite unusual kind. You obviously got lots of information out there on sites like wikipedia that people know about, but I found some rather more interesting ideas. First of all, because the internet offers videos, which flat research papers don't. So, there's lots of chemistry out there on YouTube bringing chemistry to life. You have also got unusual things like blogs, web diaries that people write and chemists now have writing blogs about research, commenting on gossip in the chemistry world and there's lot of opinions out there and some of them are quite sharp and good to read and also there's something called open notebook science pioneered by Jean-Claude Bradley in Drexel University. The ideas is that instead of recording your lab book in a hardback book, you record it not only on the internet, but open on the internet for everyone to see so that everyone can have access to the experiments that failed or the data that you would normally not have published. So, in fact, you are getting almost more information available on the internet than you would have in normal research papers.
Interviewer - Meera Senthilingam
But is this really useful to research scientists?
Interviewee - Richard Van Noorden
That's the real problem. Take blogs for example, a lot of professors would say and Steve Bachrach, a computational chemist I talked to him and he says, looking at blogs it's just random thoughts of random individuals. It takes up a lot of my day and the same goes for the free chemistry databases that there are out there. There are tens of free databases with lots of information on molecules for research chemists. You got to remember that these are not out there on their own. They are competing with very well established, paid-for, quality databases maintained by, for example, a chemical abstract service. So, these are providing data on millions of molecules for chemists to look at. Why would they bother looking in the internet for some rather haphazard voluntary information when it's already out there and in some cases you can see that open notebook science, the idea of collaborating together on the internet would give you more opportunities to do research and that's really what proponents of so-called open chemistry are angling for.
Interviewer - Meera Senthilingam
But, I have still got to ask what the point is, because who is going to actually go through all of this information?
Interviewee - Richard Van Noorden
The idea is that in web 2.0 information is linked together intelligently by computers so that, for example, you want to find out about a molecule, say acetone, you type in acetone and some intelligent machine gives you not only all the articles about acetone, but also the articles about nail polish, which is what acetone is and also the blog posts about it and maybe a 3-D picture of the molecule and maybe a link to an open notebook science lab book, where some experiment was done with acetone. Of course, this requires some kind of chemical language like the internet has been written in HTML. The chemical internet would have to be written in some kind of chemical mark-up language so search engines could search for structures, not just the text. So, this is all being developed by people like Peter Murray-Rust at Cambridge University, who coined this term open chemistry and the real challenge is that open chemistry still has to face are one, as I mentioned earlier maintaining quality. No one's paying for anyone to check out the quality of this data, because it's all free. So, while in wikipedia it's really up to the users to moderate their own data and there are few people who moderate wikipedia, can the same be done for chemistry? Second of course, you need this idea of linking data together; otherwise, as you say, it becomes a free flow where volunteered information is just haphazardly out there and it's of no real use to research scientists looking for a 10-minute quick answer to their question. But just to highlight one other really exciting idea about the internet is the idea of collaboration. So, you have virtual networks, virtual worlds such as Second Life, where people, sort of, appear on the sims-type screen and talk to each other and people are already sort of talking about chemistry and having virtual conferences on the internet and all this is very much in its infancy, very much a young movement, but no doubt the next generation of chemists will be far more familiar with all these tools and will use them as a matter of course and that's when we will probably see open chemistry come into the main stream.
Interviewer - Chris Smith
Thanks Richard and now, Victoria, we are on the trail of where chocolate came from.
Interviewee - Victoria Gill
Yeah, exactly and it's a lot older than we thought it was. It's apparently 3000 years old. A chemist called Patrick McGovern at University of Pennsylvania in the US for most of his career now he has been using chemistry to sort of put a different bit of a spin on archaeology and one of his specializations is that he looks at fermented beverages. If you find bits of ceramic that held liquids from archaeological sites, you can age the pottery using carbon dating and other techniques and then you can also take the residues from what the pottery used to hold and find out how old that is. So, you can find out about beverages, about liquids.
Interviewer - Chris Smith
So, how has he applied this to chocolate?
Interviewee - Victoria Gill
He has used a form of mass spectrometry on some residues found inside some ceremonial cups that were found in Honduras. So, these cups were dated and they were around 3000 years old and in the inside of these cups there was a tiny amount of residue from an old coco drink. Because these cups were sort of very decorative, they figured these drinks were ceremonial celebratory drinks. So, they are alcoholic beverages that were used in special ceremonies 3000 years ago.
Interviewer - Chris Smith
And how does that fit in with that sort of coco timeline we understood to be in existence before this discovery then?
Interviewee - Victoria Gill
Apparently, we understood coco to have been a form of currency for old Mesoamerican culture so Aztec cultures, but these cultures started using coco in trading and it as a very, sort of, high value, high sugar entity above 500 years beyond what McGovern has found and his group have found with their bit of chemistry. So, it has moved chocolate back further in history.
Interviewer - Chris Smith
Amazing what you confirm when you go looking far under and Ananyo one of the things you can do with a microwave is melt chocolate, but it will be a pretty small portion with this microwave wouldn't it?
Interviewee - Ananyo Bhattacharya
Yeah, that's right. It would have to be very small. So, researchers in the US have made what is probably the world's smallest microwave oven. It's thinner than human hair and can heat droplets of liquid that are smaller than a pin head.
Interviewer - Chris Smith
It sounds absolutely crazy, why would you want to do that?
Interviewee - Ananyo Bhattacharya
The idea is that you might be able to use it once it's refined in lab on chip-tape devices and those can form chemical analyses on tiny samples. Another potential use would be to use it to do the polymerase chain reaction and that's used in sort of crime labs and by molecular biologists who amplify up tiny amounts of DNA and to do that you need to be able to cycle between two or three different temperatures quite quickly.
Interviewer - Chris Smith
So, there's no danger that it might damage the nucleic acid when you microwave it?
Interviewee - Ananyo Bhattacharya
Well, only if you go over, you know, 100 degrees, so you have to be quite precise.
Interviewer - Chris Smith
But how does it work though, because that's tiny?
Interviewee - Ananyo Bhattacharya
Yeah, it is, I mean in principal it's quite similar to the way that the microwave works in your kitchen i.e., you have got microwaves that are about 12 cm wavelengths. When they hit water molecules particularly, because water molecules are charged, they begin to jostle and spin in the electric field of the microwave and as they knock against each other that creates friction and heats up your sample, but in practice it's all quite different. Your kitchen microwave uses something called a magnetron, which is a huge clunky device and it creates quite powerful microwaves than can cook your food, but you obviously can't use something like that on sample size that small. So, what they have done is they have used a signal generator and they funnelled the microwaves from that signal generator using a thin film and they have got a tiny chamber above that, which is about 7 micrometers across at its narrowest point and about 4 millimetres long and runs over this thin film.
Interviewer - Chris Smith
So, is this thin film conductive, is that how it works?
Interviewee - Ananyo Bhattacharya
Yeah, that's right. It's like a transmission line and it transmits the microwaves down to the sample.
Interviewer - Chris Smith
So, are they made actually somewhere else in the microwave generating device and then funnelled into this tiny oven?
Interviewee - Ananyo Bhattacharya
That's right, yeah they are made by the signal generator and funnelled in through this thin film, you know, you couldn't have a magnetron sitting there or some sort of device sitting there, heating the samples.
Interviewer - Chris Smith
And, is this actually in use or is this all theoretical, will we see the world's smallest microwave on the shelves so that laboratories in the US can use it quite soon?
Interviewee - Ananyo Bhattacharya
Well, unfortunately not quite yet. They have got a prototype, but it doesn't look like something that you will be seeing in any labs for a while yet, but they have got money to do.
Interviewer - Chris Smith
Thanks Ananyo. I guess, we should probably call that the micro-microwave shouldn't we. We are now back to this month's chemical conundrum and Wendi's colourful question about fireworks.
Interviewee - Ron Lancaster
My name is Ron Lancaster and I am the director and chairman of Kimbolton Fireworks and I have been specialized in making fireworks for now 30 or 40 years. The question that is being asked is whether there are any colours, which cannot be made in fireworks and of course, the clear answer is we can't do black or brown. The real question boiled down in previous times still the fact that most colours were produced from chlorates with low-temperature flames and therefore the only colours which were available were fundamental colours like blue and green, yellow and red, and silver or white, but with the introduction of high-temperature flames, which are putting the temperatures up to something more like 1500 degrees with the use of metal powders particularly magnalium, then you are able to get intermediate colours, between those prime colours. If you look at one of those old-fashioned organ consoles, where the glass comes out change colours the organist is playing, you would have noticed that if it went from say green to red, it transforms just at the certain point to just a second or two to a most beautiful orange. That convinced me that green was really quite an important factor in making a true orange in fireworks and in the same way we are able to get some very nice combinations between the blue of copper and the green of barium to give the kind of turquoise, you are able also to then have copper blue and strontium red to give one or two shades of violet and so, that really was the beginning of this sort of colour palate, which you can see now in modern fireworks. So, apart from black and brown, we think that we can make almost any kind of colour, though in fact as with a lot of firework things, it does depend on the distance at which you will see it and the atmosphere, which can also contribute to the total effect.
Interviewer - Chris Smith
Black firework, one intruding idea. Thanks very much to Ron Lancaster, Kimbolton Fireworks for that one. Now, next month, Victoria, you have got a bit of a twist in store for the chemical conundrum?
Interviewee - Victoria Gill
Yes, we do. We have a Christmas competition and we have 10 copies of Simon Basher and Adam Dingle's anarchic representation of the Periodic Table is very fun, a little periodic table book that comes complete with a poster and every element is represented by a very funky little cartoon. So, we have a question and if you can guess the element then, you can get a copy of one of these wonderful books and Mark has the clue for us.
Interviewee - Mark Peplow
That's right. You have to tell me who am I. "Quick and deadly. That's me. I put the mad in mad hatter and my ability to poison the brain is legendary. A sinister silver-coloured killer, I am a strange and stealthy liquid metal, but who am I."
Interviewee - Victoria Gill
So, if you think you know what that element is, then please send us an E-mail at Chemistry World at RSC dot org.
Interviewer - Chris Smith
And Victoria, is it just the first person who comes on to with the right answer or have you got a few copies of this.
Interviewee - Victoria Gill
We have got ten copies. So, first come first served.
Interviewer - Chris Smith
Okay, sounds intriguing. I have to go myself. Am I allowed to enter?
Interviewee - Victoria Gill
No.
Interviewer - Chris Smith
So, if you can identify that element write in now, it's Chemistry World at RSC dot org and you can also use that address to send us any feedback or suggestion about this or one of our previous programs, which was brought to you this month by Mark Peplow, Ananyo Bhattacharya, Victoria Gill, and Richard Van Noorden. The production was by Meera Senthilingam, and I am Chris Smith from the Naked Scientists dot com. From all of us here, have a wonderful Christmas and we will see you in the New Year.
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The Chemistry World Podcast is brought to you by the Royal Society of Chemistry. Look us up online at www dot Chemistry World dot org.
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