When a sample containing polysaccharides is injected into amino columns, polysaccharides are adsorbed by the packing material and it causes poor separation and/or broad peaks.
The figures below show the result when polysaccharide (pullulan, MW: 1,200,000) is injected into the Asahipak NH2P-50 4E column:
1) Figure (A) shows that there is little difference in elution time.
2) Figure (B) shows that the plate number decreses as the amount of adsorption increases.
3) Figure (C) shows the tailing in chromatogram after the adsorption.
Since it is not so easy to eliminate polysaccharides which are adorbed by the packing material, it is neccesary to pre-treat the sample and eliminate polysaccharides before injection.
Sample : Maltose, Lactose, Sucrose, Glucose, Fructose
Column : Shodex Asahipak NH2P-50 4E (4.6mmID*250mm)
Eluent : CH3CN/10mM *Tetrapropylammonium buffer(pH10.0)=75/25
Flow rate : 1.0mL/min
Detector : Shodex RI
Column temp. : 30°C
*How to make Tetrapropylammonium buffer
Please add acetic acid to 10mM Tetrapropylammonium hydroxide and adjust pH10.