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Topic: Column Chromotography - Sticky Solid/Liquid  (Read 2021 times)

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Offline Messi

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Column Chromotography - Sticky Solid/Liquid
« on: October 30, 2012, 05:01:48 PM »
Hi guys,

I just did a column, but my compound stuck to the top therefore I wasn't able to purify it. The reason my compound stuck to the top was because it was a gooey/sticky solid liquid.

How should I purify/separate such compounds?

I was scared initially that I wouldn't be able to grab my compound that was stuck at the top of my column, but luckily I used my best friend DCM and after many squirts with my pipette, my "stick solid/liquid" finally came out! :)

Offline discodermolide

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Re: Column Chromotography - Sticky Solid/Liquid
« Reply #1 on: October 30, 2012, 10:05:40 PM »
I don't know how much you have. Sometimes I used to pre-absorb the compound on silica-gel by dissolving it in DCM then adding some silica-gel, removing the solvent. When you have a nice dry powder add it to the top of the column and elute as you normally would.
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Offline Doc Oc

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Re: Column Chromotography - Sticky Solid/Liquid
« Reply #2 on: October 31, 2012, 02:11:47 PM »
Did you do any TLC's to verify that your compound would move under the conditions you used?  The physical state of it should only be an issue during the loading.  For very thick syrups, I do the same thing discodermolide mentioned.  I liked the technique so much I dry load most compounds, even if they flow freely in and out of a Pasteur pipet.

Offline Messi

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Re: Column Chromotography - Sticky Solid/Liquid
« Reply #3 on: October 31, 2012, 05:15:20 PM »
Thank you kindly. I had never heard of this dry-loading technique. Seems excellent! Thanks!

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