By Anonymous on Friday, May 28, 2004 - 01:24 pm:
Any one find a column suitable for EDTA?
I have some sucess including peek/teflon tubing throught system
Have no conductivity detector
Looking for a column and optimum pH and separation from benzyl alcohol
By Chris Pohl on Saturday, May 29, 2004 - 04:40 pm:
Most anion exchange columns designed for Ion Chromatography will work for EDTA determinations. An example on the PRP-X100 column is found on the Hamilton web site: http://www.hamiltoncomp.com/product/hplc/prpx100.html Another choice is the IonPac AS7 from Dionex: http://www1.dionex.com/en-us/webdocs/datasheets/datasheets/datasheets/AS7_V19.pdf The latter illustrates colorimetric detection under non-complexing conditions. This method is advantageous when the EDTA is present along with various metals. By operating at a pH low enough to break up any metal-EDTA complexes, determination of total EDTA is possible.
By Brent on Monday, May 31, 2004 - 02:50 pm:
There is a reverse-phase ion-pair method: Loyaux-Lawniczak, S., Douch, J., Behra, P. Fresenius J Anal Chem 364, 727-731 (1999)
Basically, in a sodium acetate buffer the EDTA is complexed with Iron using FeCl3 and detected by UV absorbance.