Re: sec baseline
Posted: Fri Oct 07, 2011 9:19 pm
I am using a binary agilent 1100 series pump. When purging the lines A and B at 5 mL per min to waste I heard clicking from the pump A (could feel it clicking too). It cause spikes in pressure but went away after a while. I rinsed those lines with a lot of water.
After purging all lines, sample cell, and reference cell with water, ethanol, water again, and after cleaning the column with 10%DMSO and re equilibrating with mobile phase, my noise went from 500 nRIU to 5 nRIU. However, when I purged the reference cell my noise went up to 50 nRIU and now it's up to 100 nRIU.
Could that valve in the RI, from purge ref cell to sample cell, cause pressure variations which might cause RI baseline noise? If so how to fix that? I'm pretty sure this is where the problem is. This morning the baseline was lovely, then I purged and it went back to bad.
After purging all lines, sample cell, and reference cell with water, ethanol, water again, and after cleaning the column with 10%DMSO and re equilibrating with mobile phase, my noise went from 500 nRIU to 5 nRIU. However, when I purged the reference cell my noise went up to 50 nRIU and now it's up to 100 nRIU.
Could that valve in the RI, from purge ref cell to sample cell, cause pressure variations which might cause RI baseline noise? If so how to fix that? I'm pretty sure this is where the problem is. This morning the baseline was lovely, then I purged and it went back to bad.