By Jessica on Tuesday, June 29, 2004 - 10:54 am:
I am currently trying to develop a reverse-phase method for the detection of EDTA. Has anyone ever had any success with this type of method? And if so, do you have any advice for me?
By Consumer Products Guy on Tuesday, June 29, 2004 - 11:20 am:
We use copper and quaternary ammonium salt -containing mobile phase on RP-8 and UV detection at 290nm. Unfortunately, we consider this procedure proprietary so I can't share more.
By Anonymous on Tuesday, June 29, 2004 - 12:18 pm:
On the metrohm web site there are details on how to do NTA, EDTA and DTPA using prontosil 120-5ODSAQ reverse phase column and UV detection and the Metrohm suppressor. Eluent is 0.5mmol/L HNO3, 2.5mmol/L tetrabutylammonium hydroxide, 7.5mmol/L tetrabutylammonium sulphate, 5 % methanol at 1.0ml/min flow rate. You can purchase the Metrohm suppressor separately and add it to any HPLC system. This is quite easy to do. see link for applic details
http://www.metrohm.com/infocenter/download.php4?doc=applications/notes/pdf/s36.pdf
You have to register your details.
good luck
By Anonymous on Wednesday, June 30, 2004 - 01:21 pm:
Check out Alltech, 100 x 4.6 mm cation/S column, 1.5 mM sulfuric acid at 1 mL/min UV at 210 nm (free EDTA) or 100 x 4.1 mm PRP-X100 column, 3 mN sulfuric acid at 2 mL/min UV at 254 nm. (The PRP-X100 column is actually Hamiltons. Both these methods may be better if you are not looking for very low levels of EDTA. Bonus is no suppressor is needed and if you talk with the vendors the methods are not proprietary.
Regards,
Mark