SB column mobile phase

Record: 362

Category: Specifications
Product: SB-806, SB-803
Sample:

Question
compound not eluting. Seems like there’s ionic interaction. Using 0.01M ammonium acetate/20%ACN mobile. pH ~4.4. compound -basic

Answer
We have applications on polyacrylamide analysis using 0.2M NaCl aq mobile.
http://shodex.net/index.php?seitenid=1&applic=1078
So you could try increasing the salt concentration to see if it helps or..as you mentioned changing pH.
I think ammonium acetate has buffering capacity around pH 7 as well as 4.4.
So you could try neutral condition first if you like or use ~10mM ammonium bicarbonate/phosphate buffer (pH~9)

 
 
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