Dear all,
I got a lot of salt crystals in reservior solution (well solution), which
contains 0.1 M phosphate/citrate ph 4.2, PEG200 47%, EDTA-2Na 0-22mM.
Reservior solution appears crystals from 12mM EDTA. Could someone help me to
explain why?
Thank you very much!
Yibin
The pH is too low and the EDTA is insoluble. You need to be above pH ~8.0.
Your best bet is to try another chelator.
James
On Feb 21, 2011, at 2:22 PM, Yibin Lin wrote:
> Dear all,
>
> I got a lot of salt crystals in reservior solution (well solution), which
> contains 0.1 M phosphate/citrate
What other cations are present? Any divalent cations like Mg++ or Ca++?
The Ksp of magnesium phosphate is about 10^-24, so even if you have a very
small amount present, say as a contaminant with citrate or EDTA, it will
crystallize.
On Feb 21, 2011, at 1:22 PM, Yibin Lin wrote:
> Dear all,
No, there are not any other cations, so I feel very strange. Everything
brought from sigma.
On Tue, Feb 22, 2011 at 8:58 PM, William Scott wrote:
> What other cations are present? Any divalent cations like Mg++ or Ca++?
>
> The Ksp of magnesium phosphate is about 10^-24, so even if you have a
No, there are not any other cations, so I feel very strange. Everything
brought from sigma.
Nothing's strange. EDTA is very poorly soluble at pH 4.2 and would
become even less soluble in the presence of 47% PEG. So it crystallizes.
Dima
On Tue, Feb 22, 2011 at 8:58 PM, William Scott
<
someone can help me to explain why EDTA-2Na can
formate salt crystals
No, there are not any other cations, so I feel very strange. Everything brought
from sigma.
On Tue, Feb 22, 2011 at 8:58 PM, William Scott
mailto:wgsc...@ucsc.edu>> wrote:
What other cations are present? Any divalent c