Any harm in using excess solvent if salting out?

[Jagube]

I understand that with freeze-precipitation we don't want to use too much solvent as we want the solvent saturated with the goodies for the freeze-precipitation to be efficient.

However, when using limonene or vegetable oil and salting out with vinegar (or one of the fumaric acid precipitation teks), is there any harm in using plenty of solvent? I'd rather do few large pulls than many small ones. Especially since it's hard to baste off the last few mm of the solvent, as the basic soup gets pulled up by the pipette.

I understand the acid washes of the solvent may be a bit less efficient, but that seems to be less of a concern to me.

 

[blue.magic]

It's okay as long as the salt solubility in the organic layer is negligible. I am not sure about limonene, chemists here might advice - this probably depends on how polar it is. For backsalting, you want to use as nonpolar solvent as possible.

It will theoretically take more time and labour to salt out everything when more solvent is used.

But most likely you should be fine. Experiment is king though.

 

[pete666]

If you don't mind you use a lot of solvent and have more work with pipetting, no problem I would know of. Maybe just a bit longer mixing. That's one of the benefits of back-salting, you don't care how much solvent you use and you don't have to evaporate anything.

I always leave there some solvent to be sure I don't suck water soup, but not more than 20%.
Last pull the bottle with water soup is fully filled up with water to get the solvent to the neck of the bottle, where 99% can be acquired.