j*******x
发帖数: 22 | 1 知道版内挺多高手, 请教一下有关HILIC的问题.我用 ployhydroxyenthyl A pack 了一
根 75 microI.D.的column， 用UV 检测，现是用mobile phase A: 100% H2O B:100%
ACN 分typtic peptide, 在gradient里一个peak都看不到，又用了 mobile phase A:
100% H2O with 0.1% TFA B:100% ACN with 0.1%TFA.还是在gradient里一个peak都看
不到
后在Mobile pahse 里加了20mM 的盐，现在可以看到两个bubles...., 观测到column德
pressure跳来跳去的厉害，不知道问题在哪？？ （flow rate :250-300 nL/min, ACN
80-30 in 30 mins) | e*****r
发帖数: 379 | 2 One poss reason: MeCN too high!
try 90 or 85% MeCN
with some ammonium acetate. | m****e
发帖数: 255 | | E****F
发帖数: 10 | 4 Usually, people don't use 100% solvent as mobile phase, or it might minimize
the efficiency of the column. What we do is preparing 95/5 H2O/ACN with 0.1
% Formic Acid (or whatever you choose such as 0.1% TFA) as solvent A; 90/10
ACN/H2O with 0.1% Formic Acid as solvent B.
If you see some bubbles ocurring, that might be arised from your loading
pressure, flow rate,etc. One solution is to purge the chromatographic system
including loading and waste lines by using 2-propanol, then to increase the
f | j*******x
发帖数: 22 | 5
ACN
【在 j*******x 的大作中提到】
: 知道版内挺多高手, 请教一下有关HILIC的问题.我用 ployhydroxyenthyl A pack 了一
: 根 75 microI.D.的column， 用UV 检测，现是用mobile phase A: 100% H2O B:100%
: ACN 分typtic peptide, 在gradient里一个peak都看不到，又用了 mobile phase A:
: 100% H2O with 0.1% TFA B:100% ACN with 0.1%TFA.还是在gradient里一个peak都看
: 不到
: 后在Mobile pahse 里加了20mM 的盐，现在可以看到两个bubles...., 观测到column德
: pressure跳来跳去的厉害，不知道问题在哪？？ （flow rate :250-300 nL/min, ACN
: 80-30 in 30 mins)
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