Sciencemadness Discussion Board

Strontium Ranelate

Tdep - 3-2-2013 at 00:26

Hey! New guy here, but i'm loving this site right now :D

So I came across this drug Strontium ranelate. I picked up a few grams because it's not often I cross paths with strontium chemicals. When I got home I added a few mills of HCL which dissolved the ranelate and turned just a slight off yellow colour. Assuming i'd made SrCl2 and ranelic acid I went to heat the solution to crystalise out the chloride.
Yet this is where I start to get confused. The solution went from off white to a light pink pretty quickly, and being distracted by my blowtorch going a deep red when tiny amounts of solution were kicked up into the flame I didn't stop the heating and before I knew it my solution of supposedly SrCl2 was a deep purple.

It looks exactly similar to permaganate solution, maybe with a touch more blue. Thinking I could get the Strontium out by reacting it with bicarb, I added a small amount of the purple solution to a bicarb solution and the purple first flashed a blue and then stayed a deep green.

What's going on here? I started with pure chemicals. It was some of the most beautiful chemistry colourwise that i've witnessed, but why isn't it a clear solution, as expected? Did I decompose something, or is this mysterious 'ranelate' doing some crazy thing?
Thanks :)

phlogiston - 3-2-2013 at 06:51

I would guess the ranelate decomposed upon heating.

One way to recover the strontium from the solution is to add a sulfate, or sulfuric acid. You should get a fine precipitate of strontium sulfate. It should then be possible to convert this to strontium carbonate by fusing with sodium carbonate.


Boffis - 3-2-2013 at 07:48

Seems an awfully expensive way of buying Sr!! But the renalate bit sounds interesting.

I agree that the best process would be to seperate the strontium with say sodium or ammonium sulphate and then recrystallise the alkali /ammonium renelate because it sounds like free renelic acid is sensetive to mineral acid hydrolysis (it is a 2-amino-3-cyanothiophene derivative). Its a complexing agent so you may find that sulphates don't precipitate the Sr and you may have to try sodium or potassium carbonate. (Sr carbonate is much less soluble than the sulphate in neutral/ alkaline conditions).

Tdep - 3-2-2013 at 18:43

When I say I picked it up I really mean I got it for free haha. The perks of having a mum as a nurse :D

I'll try adding pottasium sulphate. I'll let you know how it goes.

Adding the purple solution to sodium hyrdoxide yeilds a brick red coloured solution. If I tried, I reckon I could get every colour of the rainbow out of it.