Baseline Drops

[nbarti]

I've been running fatty acids for a few years on a 6890 FID, using a RT-2560 100m column. In the last week, I've gotten some bizarre baseline spikes in the middle of my chromatograms, with my baseline dropping from 15500 to 12000 in an instant, sometimes in the middle of an analyte eluting. I've never seen this issue before, and was hoping one of y'all had seen this and knew how to fix it. I've linked an image of the readout below. Thanks!

https://imgur.com/49ipr1f

[DR]

Rod's Rule - the more you do not tell us, the more we cannot help.

Are you derivitizing your FAs - ie what you are injecting is fatty acid methyl-esters? If so, have you had to change vendors, lots or anything else in your prep routine? It strikes me that 100m may be overkill, but you neglect to mention the diameter and coating thickness of your column (along with many other things). Could your column just be on the verge of wearing out? Are these drops at all consistent with respect to timing or magnitude? Have you tried a different column, fresh gasses, fresh traps for things you don't want in your gasses?