Chemical Forums
Chemistry Forums for Students => Analytical Chemistry Forum => Topic started by: Yôme on June 24, 2008, 08:19:22 AM
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Hi everybody !
I have a problem concerning the analysis of sugars (arabinose, glucose, mannose...) from wood with ionic chromatography (HPAEC). The mannose elutes very slowly so that I cannot measure the real concentration in my samples. This fact is very strange because the other sugars (arabinose, galactose, glucose and xylose) are not affected. I regenerated the column and it was a little bit better but after a few injections, the same problem occured again. Even with a new column, the problem remained. Please, help me !
For information I use Dionex chromatography equipment (DX 500) with a GP 40 pump and a ED40 electrochemical detector (with a gold electrode). The column is a Carbopac PA1 and the method is in 2 steps (analysis : 98 % H2O, 2% NaOH 0.2 M; washing : 100% NaOH 0.2 M).
I would be very pleased if someone could help me !
Thanks.