The complex of Fe2+-EDTA is stronger than Fe2+-NTA. I would like to know some other differences. Is it possible that two NTA molecules bind with one Fe2+ ion, which is not possible with EDTA .
It is possible to form complexes with two NTA ligands, but I'm not certain if it has been reported with iron(II). I don't see why not. Iron loves nitrogen containing ligands.
For more information I refer you to the following:
http://pac.iupac.org/publications/pac/pdf/1982/pdf/5412x2693.pdf
http://www.dojindo.com/Images/Product%20Photo/Chelate_Table_of_Stability_Constants.pdf
Perhaps these are not the answers that you're looking for, but you may find them interesting.
In Fe(II)-EDTA complex, iron atom is coordinated with 4 COOH groups and two N atoms. In Fe-NTA, with 3 COOH and one N. This is the main reason for lower stability. It is possible to imagine a NTA-Fe_NTA complex, however I am not sure that it would be stable (sufficiently stable to avoid disproportionation to NTA-Fe and NTA).
Dr. Dubey and Dr. Carraher
Thank you for the responses. Very helpful.
I am just not sure about the conditions (pH etc.) under which formation of NTA-Fe-NTA would occur and remain stable.
If we take 'equimolar' amounts of Fe2+ and NTA in a solution at around pH 2-3, could it be possible that half of the Fe2+ bind to all the NTA molecules while half of the Fe2+ remain free !!
Thanks !!
- Badges
- Science topic
- Similar topics
- Chemistry