From: Richard Prankerd (Richard.Prankerd$##$vcp.monash.edu.au)
Date: Mon Jun 25 2007 - 19:08:24 EDT
A classical assay (provided there are no other chelating agents present) is to titrate the EDTA with divalent cations, especially Mg2+, using a suitable indicator at about pH 10. This titration was commonly used in reverse to assay low concentrations of divalent metal ions. Even mixtures could be titrated, using suitable masking agents.
If concentrations of EDTA are very low, or if other complexing agents are present, then a chromatographic (HPLC) method using an anion exchange column and an aqueous buffer mobile phase will work, using detection by UV at 220-230 nm. The mobile phase pH will need to be manipulated to get best separation from other anions and complexing agents - below 7 will probably be needed.
Rgds
Richard
-----Original Message-----
From: everybody-bounces$##$orglist.net on behalf of A.R. Shirmohamadi
Sent: Tue 6/26/2007 2:30 AM
To: everybody$##$orglist.net
Subject: ORGLIST: EDTA 4Na
Dear Colleagues
Can anyone recommend a way of assay about "EDTA tetrasodium salt" in a solution?
Any suggestions would be greatly appreciated.
Thanks in advance,
Shirmohamadi
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