post-column obstruction
Posted: Fri Jun 03, 2011 9:43 am
Dear all,
I am doing LC/MS analyses using capillary LC. I use 50 um ID Peeksil tubing. Most of the time this works fine. However, I sometimes get post-column obstructions. I find it difficult to find an explanation for these post-column obstructions. I can imagine getting pre-column obstruction, for instance due to sample impurities. Is there anyone that has an explanation for this phenomenon? My system setup is the following: Mobile phase A, 5 mM ammium acetate, mobile phase B, 97.5 % acetonitrile, 2.5 % water, 5 mM ammonium actetate. I run gradients from 10%B to 100% B. The flow rate is approximately 20 ul/min (I am using a flow splitter to get these low flow rates).
I hope someone has an explanation for this so I can change my setup and prevent these sometimes annoying obstructions.
Koen
I am doing LC/MS analyses using capillary LC. I use 50 um ID Peeksil tubing. Most of the time this works fine. However, I sometimes get post-column obstructions. I find it difficult to find an explanation for these post-column obstructions. I can imagine getting pre-column obstruction, for instance due to sample impurities. Is there anyone that has an explanation for this phenomenon? My system setup is the following: Mobile phase A, 5 mM ammium acetate, mobile phase B, 97.5 % acetonitrile, 2.5 % water, 5 mM ammonium actetate. I run gradients from 10%B to 100% B. The flow rate is approximately 20 ul/min (I am using a flow splitter to get these low flow rates).
I hope someone has an explanation for this so I can change my setup and prevent these sometimes annoying obstructions.
Koen
