Chromatography Forum

Hi,

I am currently trying to separate out polymers using SEC * RP. In the beginning I had smooth chromatograms, but all of a sudden the chromatograms have started showing a zigzag pattern in the second dimension. I have attached an image below:

https://ibb.co/fxWvKv2


I was wondering if anyone knows what could cause this problem or has any suggestions on how to fix it? The lamp has just been replaced, so I was wondering if this means the problem could lead to the flow cell or the pump?

Thanks!

It looks like a trouble in the 1st dimension rather than in the 2nd dimension.

That is an iso plot, not a chromatogram. Yes, first dimension is of concern and "2D" not relevant. An iso plot is Not very useful for troubleshooting in this case, but you can see how the spectra are very weak so the: sample concentration might have poor, pump/baseline noise high or the method poor. This is a training issue and the method needs to be reviewed by someone with experience on-site to provide more constructive info.