Milking the Thorium Cow - Periodic Table of Videos

[Music] today's video is about milking the thorium cow it's an amazing piece of science before we start there are two or three things that I need to tell you so you can understand quite how fantastic it is the first thing is that to treat cancer one can use highly radioactive atoms which are taken to the tumor by complexing them that's binding them to a protein that is attracted to the tumor rather than rest of the body the second point is that when a radioactive element decays the products of the decay can be far more radioactive than the original atom that decays you can have thorium that's not very radioactive decaying into something that's much more radioactive and the third point just before we start is that when you have a really radioactive atom even a nanogram that is ten to the minus nine of a gram a thousand millionth of a gram has more than a hundred times as many atoms as there are cells in your body so you need only a tiny amount of this highly radioactive material to give a really big dose to the tumor so Brady was at the Oak Ridge National Lab in Tennessee in the United States and he was given a tour by Rosebowl who is an expert in the handling of these highly radioactive elements we are at building 79 20 this is the small hot cell room we call them Ches this is where we do a lot of our medical isotope purification or the starting part of it and we'll show you the rest of it later some of the material we work with is very highly radioactive and so we need shielding to protect us from the dose from that material so we worked with it with remote handles this is Jay who is doing the operation of the remote operators here we call them manipulators and he's going to show us the thorium-229 cow that were used to milk our medical isotopes from the guy who was doing it looked like a magician it was amazing how he could manipulate these robot arms do you think you'd be good at it I'm sure I'd be terrible Ithorian was dissolved in nitric acid that's how we store it we don't want to take it back to the solid it becomes a very insoluble oxide so we keep it in liquid solution the thorium Cao is a sample of thorium-229 they thought it was just waste but then they suddenly realized this fantastic application and it's called the cow because it keeps on giving more and more actinium just in the same way that a cow keeps on giving milk but the difference is you don't have to feed the thorium but you do have to feed a cow [Music] yeah this is old material but at the time that it was made we didn't have a medical isotope application so this was something that would have been thrown away as waste material that we were able to go and recover something very useful out of it the chemistry will puts the physics behind it is that thorium-229 gives out an alpha particle which has mass 4 and contains 2 protons so you go to elements to the left to radium and then the radium gives out a beta particle that's an electron and it goes one element to the right and you get two actinium 2 to 5 the first stage of the milking is to remove the thorium from solution so that you can then process the actinium and they do this with a resin a solid acid which is something like this material here this is also a solid acid essentially tiny pellets of polystyrene which have been treated so they have acid groups on it see the columns he's pulled that rack out off you notice it was up against the wall to start with our thorium we run it through that column to separate it from the actinium that's an anion exchange column it has a glass frit on the top that holds the resin down for when we dump water on top it doesn't disturb the resin bed and it's stored with water on it right now until we go to do the next run the next separation run so there's nothing regular active environment you're not so you no not in that column in fact we keep our radioactive material off of the column between runs because if the radiation will destroy the resin so now they have solution which contains actinium and some radium that he put it through series of other columns to purify it with resins and they adjust the acidity of the solution so that first of all the radium is removed and eventually all they're left with is pure actinium and today we're packaging it in small glass vials in order to ship it to the customer so over on this next place here this is where they're doing the evaporation of the material they are only going to produce a sample of about an anagram an anagram is such a small amount of material that you can't actually see it the problem is that whoever is going to buy it needs to know where it is so they use a bottle which has a v-shaped bottom conical bottom so as you concentrate the liquid it goes right down to the bottom we try to evaporate it down in the V part the very bottom because the customers usually dissolve this up in about 100 or 200 microliters of solution which is about two to three drops they evaporate it and you get the bottle and right at the bottom is a tiny bit of actinium so the question is how do they know if they've got a new there and they have an extraordinarily cunning piece of kit which they call the gamma ray camera which measures some of the gamma rays that are given out by the actinium when it decays the gamma ray is like light beam or photon of light both very short wavelength so we'll go through a lot of materials including through the shielding at the front of the box another way you can see the element is that as it decays it actually gives out a glow of blue light the glow is pretty weak so if you want to photograph it you have to switch out all the lights and do a long exposure [Music] they're banging out the dry actinium two to five so we took it to complete dryness in those glass vials so she'll work it all the way down to the bottom of the bag then a heat seal across there the plastic is melted there to advance [Music] I should say they sell the bottle for $1000 just wait a moment a thousand dollars for one thousandth of a microgram means that you would have to pay a thousand million dollars for a gram of this material of course you couldn't make a gram of this material and it would be so radioactive that nobody could handle it but that just gives you an idea of the sort of price of this material they use it to make medications and so the minute this is actually they tell me is one of the less expensive ingredients necessarily in the final medicine once they get it made we're very motivated by the fact the application everybody knows somebody who's had cancer or some family member that has cancer and is dealing with that so we're very excited to be able to work with something that we know gets immediate application you know a lot of the research that we do down the road it might develop into something but ours it goes out weekly for patients to be treated so it's very nice being that closely connected with the prior [Music]

Channel: Periodic Videos

Views: 378,938

Rating: 4.9562492 out of 5

Keywords: periodic, videos, chemistry, actinium, thorium

Id: DmczVhGq8cU

Length: 9min 34sec (574 seconds)

Published: Fri Jan 11 2019

Reddit Comments

[u/GreenChileEnchiladas]

Fantastic video. I've been watching your videos religiously, and am always happy when a new Periodic Tables video comes out.

Except for the Deep Sky videos, Periodic Tables are my favorite. Keep up the good work!

[u/KorbussaMaro]

I was fully expecting to see a poor cow being milked for it's radioactive milk. Spoiler: it's a metaphoric cow. :)

[u/spice_up_your_life]

Really enjoyed this. Can we expect more nuclear vidios from your visit to ORNL?