The one we use all the time is the NMR spectrometer. Seen an MRI scanner in a hospital, or on House? People get put into this big tube and you can see inside them on a computer screen? NMR is just like that except we put chemicals in to the big hollow bit rather than people.
So you get your sample in a little tube. You lower it down into this chamber and you spin it. The machine blasts it with a serious amount of radio waves. Very high energy, focussed on the molecules. The nuclei of the atoms in there get excited and they all line up, like soldiers in formation. You switch off the radio waves and the nuclei kind of relax back to how they were before. (If you want to talk about this to a chemist you’d say “The nuclear spins all align, then relax”) When the nuclei relax they give off a little bit of energy. You detect that (using the machine). You can then use a powerful computer to convert those signals into a picture of what the molecule looks like.
It’s just like hitting a bell. You hit it, then listen to the sound. The sound is actually a bunch of really complicated vibrations in the air, but your brain (your head computer) converts that into notes that you can understand.
The NMR machine manages to do this by having a very strong magnetic field at the centre. It does that by using an electromagnet – so a magnet that’s created by a very strong electrical current. To get so much current you have to use a “superconducting” magnet, which means it’s made of wires that have no resistance. To get THAT means you have to cool the magnet way down. So actually the NMR machine is pretty big (bigger than a person – some of the new ones are as big as cars) and that’s basically because the magnet is suspended in super-cooled liquids like liquid nitrogen – that’s the stuff you normally breathe in in the air, but cooled to around -200 degrees C. In fact the machine is even colder than that – it’s liquid helium right in the middle, and that’s seriously cold.
My students use this machine every day. “NMR” stands for Nuclear Magnetic Resonance. You never normally see these in everyday life because they’re expensive (a million bucks a shot). We have a few here in the School of Chemistry:
The magnet’s so strong that you can’t go into the NMR room if you have a pacemaker (heart controller) and you have to leave your credit cards at the door otherwise it’ll wipe them. 😛
I would say the PCR (polymerase chain reaction) machine. We use it to make many copies of a section of DNA.
Polymerase is an enzyme (a protein which helps reactions to occur) which sticks together the pieces of DNA, called ‘nucleic acids’. You have to start with the section of DNA you are interested in. DNA is usually found as two matching strands stuck together.
What happens in this reaction is that the strands are peeled apart, then polymerase makes two new copies by adding in new nucleic acids to match the pieces of DNA you already have. So you get 2 sets of double-stranded DNA, which look identical.
These 2 sets are then peeled apart and filled in to produce 4 sets of identical double-stranded DNA. This goes on for many cycles, with the number of copies doubling each cycle, eg. 2, 4, 8, 16, 32, 64, 128, 256 etc.
You end up with thousands of identical copies from the single section of DNA that you started with. This is useful because it is very hard to study one piece of DNA. When you have thousands of pieces you can find out the sequence of the DNA. The sequence of DNA can then tell you if a person has a particular genetic disease or an infectious disease.
It is also used in forensic testing to determine if a skin, hair, blood or other biological sample has come from a particular person (you match the sample found at the scene to a sample from the person. If certain parts of DNA have the same sequence then it is likely that the samples were from the same person).
Things like the NMR spectrometer are in our shared facilities. My lab. I try to do things that do not take much equipment so most people wouldn’t find them “cool”. Right now I am working on a biodiesel synthesis from used cooking oil — no not forensic science — but this is on a small scale using 50 mL flasks and so on. Then the biodiesel undergoes a flammability test with a “home-made” oil lamp. I find it “cool” to have “home-made” equipment, but some people think that is uncool to be unsophisticated.
I have heard of a lab in Denmark (the home of Lego) that uses Lego robotics. Here is a link to an article building a spectrometer from Lego . No I do not have one (yet) but would love to have a lab made from Lego.
One of the coolest machines in my lab measures the heartbeat of baby lizards while they are still in the egg.
You put the egg on the platform of the machine and the machine can count the tiny vibrations coming from the egg when the lizard’s heart beats.
Some eggs never hatch because for some reason the baby lizard dies before it is born. We use this heartbeat machine to test whether eggs are alive or dead. We can also see how fast the baby lizard’s heart is beating to see whether the baby is stressed.
The one we use all the time is the NMR spectrometer. Seen an MRI scanner in a hospital, or on House? People get put into this big tube and you can see inside them on a computer screen? NMR is just like that except we put chemicals in to the big hollow bit rather than people.
So you get your sample in a little tube. You lower it down into this chamber and you spin it. The machine blasts it with a serious amount of radio waves. Very high energy, focussed on the molecules. The nuclei of the atoms in there get excited and they all line up, like soldiers in formation. You switch off the radio waves and the nuclei kind of relax back to how they were before. (If you want to talk about this to a chemist you’d say “The nuclear spins all align, then relax”) When the nuclei relax they give off a little bit of energy. You detect that (using the machine). You can then use a powerful computer to convert those signals into a picture of what the molecule looks like.
It’s just like hitting a bell. You hit it, then listen to the sound. The sound is actually a bunch of really complicated vibrations in the air, but your brain (your head computer) converts that into notes that you can understand.
The NMR machine manages to do this by having a very strong magnetic field at the centre. It does that by using an electromagnet – so a magnet that’s created by a very strong electrical current. To get so much current you have to use a “superconducting” magnet, which means it’s made of wires that have no resistance. To get THAT means you have to cool the magnet way down. So actually the NMR machine is pretty big (bigger than a person – some of the new ones are as big as cars) and that’s basically because the magnet is suspended in super-cooled liquids like liquid nitrogen – that’s the stuff you normally breathe in in the air, but cooled to around -200 degrees C. In fact the machine is even colder than that – it’s liquid helium right in the middle, and that’s seriously cold.
My students use this machine every day. “NMR” stands for Nuclear Magnetic Resonance. You never normally see these in everyday life because they’re expensive (a million bucks a shot). We have a few here in the School of Chemistry:
http://www.chem.usyd.edu.au/~long/hardware.html
If you ever get to visit a chemistry department at Uni, ask to see the NMRs. Here’s a picture of one. They’re like huge silver bullets.
http://www.nmr.utmb.edu/
The magnet’s so strong that you can’t go into the NMR room if you have a pacemaker (heart controller) and you have to leave your credit cards at the door otherwise it’ll wipe them. 😛
1
I would say the PCR (polymerase chain reaction) machine. We use it to make many copies of a section of DNA.
Polymerase is an enzyme (a protein which helps reactions to occur) which sticks together the pieces of DNA, called ‘nucleic acids’. You have to start with the section of DNA you are interested in. DNA is usually found as two matching strands stuck together.
What happens in this reaction is that the strands are peeled apart, then polymerase makes two new copies by adding in new nucleic acids to match the pieces of DNA you already have. So you get 2 sets of double-stranded DNA, which look identical.
These 2 sets are then peeled apart and filled in to produce 4 sets of identical double-stranded DNA. This goes on for many cycles, with the number of copies doubling each cycle, eg. 2, 4, 8, 16, 32, 64, 128, 256 etc.
You end up with thousands of identical copies from the single section of DNA that you started with. This is useful because it is very hard to study one piece of DNA. When you have thousands of pieces you can find out the sequence of the DNA. The sequence of DNA can then tell you if a person has a particular genetic disease or an infectious disease.
It is also used in forensic testing to determine if a skin, hair, blood or other biological sample has come from a particular person (you match the sample found at the scene to a sample from the person. If certain parts of DNA have the same sequence then it is likely that the samples were from the same person).
0
Things like the NMR spectrometer are in our shared facilities. My lab. I try to do things that do not take much equipment so most people wouldn’t find them “cool”. Right now I am working on a biodiesel synthesis from used cooking oil — no not forensic science — but this is on a small scale using 50 mL flasks and so on. Then the biodiesel undergoes a flammability test with a “home-made” oil lamp. I find it “cool” to have “home-made” equipment, but some people think that is uncool to be unsophisticated.
I have heard of a lab in Denmark (the home of Lego) that uses Lego robotics. Here is a link to an article building a spectrometer from Lego . No I do not have one (yet) but would love to have a lab made from Lego.
0
One of the coolest machines in my lab measures the heartbeat of baby lizards while they are still in the egg.
You put the egg on the platform of the machine and the machine can count the tiny vibrations coming from the egg when the lizard’s heart beats.
Some eggs never hatch because for some reason the baby lizard dies before it is born. We use this heartbeat machine to test whether eggs are alive or dead. We can also see how fast the baby lizard’s heart is beating to see whether the baby is stressed.
0