Chromatography Forum

I am analyzing fermentation broth for ethanol using gc ms. Everything is going well during real time analysis.
However when I go to post run analysis, the zoom chromatogram view does not show any chromatogram (even though there is a chromatogram shown on the tic window).
I compared it to other chromatograms (from other runs using different samples) and the thing that I noticed is that on the upper left corner of the zoom chromatogram view mine shows 272.0 while those from other runs show TIC.
I really can't figure it out. What does this mean?

I am analyzing fermentation broth for ethanol using gc ms. Everything is going well during real time analysis.
However when I go to post run analysis, the zoom chromatogram view does not show any chromatogram (even though there is a chromatogram shown on the tic window).
I compared it to other chromatograms (from other runs using different samples) and the thing that I noticed is that on the upper left corner of the zoom chromatogram view mine shows 272.0 while those from other runs show TIC.
I really can't figure it out. What does this mean?

speak spanish?

"I am analyzing fermentation broth for ethanol using gc ms. Everything is going well during real time analysis.
However when I go to post run analysis, the zoom chromatogram view does not show any chromatogram (even though there is a chromatogram shown on the tic window).
I compared it to other chromatograms (from other runs using different samples) and the thing that I noticed is that on the upper left corner of the zoom chromatogram view mine shows 272.0 while those from other runs show TIC.
I really can't figure it out. What does this mean?"

It sounds like you're looking at a specific ion signal (m/z 272.0) in the empty window, rather than at the TIC. That would explain why you aren't seeing anything, if there's nothing to see. Without knowing what software you're using, though, it's hard to say more

"I am analyzing fermentation broth for ethanol using gc ms. Everything is going well during real time analysis.
However when I go to post run analysis, the zoom chromatogram view does not show any chromatogram (even though there is a chromatogram shown on the tic window).
I compared it to other chromatograms (from other runs using different samples) and the thing that I noticed is that on the upper left corner of the zoom chromatogram view mine shows 272.0 while those from other runs show TIC.
I really can't figure it out. What does this mean?"

It sounds like you're looking at a specific ion signal (m/z 272.0) in the empty window, rather than at the TIC. That would explain why you aren't seeing anything, if there's nothing to see. Without knowing what software you're using, though, it's hard to say more

Ok, Can you put a photo?

here's the photo


back to the future errors

"I am analyzing fermentation broth for ethanol using gc ms. Everything is going well during real time analysis.
However when I go to post run analysis, the zoom chromatogram view does not show any chromatogram (even though there is a chromatogram shown on the tic window).
I compared it to other chromatograms (from other runs using different samples) and the thing that I noticed is that on the upper left corner of the zoom chromatogram view mine shows 272.0 while those from other runs show TIC.
I really can't figure it out. What does this mean?"

It sounds like you're looking at a specific ion signal (m/z 272.0) in the empty window, rather than at the TIC. That would explain why you aren't seeing anything, if there's nothing to see. Without knowing what software you're using, though, it's hard to say more

If this is the case, how do I change the it to TIC? I am using Shimadzu TQ series. I also put a photo on my previous reply. Thank you!

"I am analyzing fermentation broth for ethanol using gc ms. Everything is going well during real time analysis.
However when I go to post run analysis, the zoom chromatogram view does not show any chromatogram (even though there is a chromatogram shown on the tic window).
I compared it to other chromatograms (from other runs using different samples) and the thing that I noticed is that on the upper left corner of the zoom chromatogram view mine shows 272.0 while those from other runs show TIC.
I really can't figure it out. What does this mean?"

It sounds like you're looking at a specific ion signal (m/z 272.0) in the empty window, rather than at the TIC. That would explain why you aren't seeing anything, if there's nothing to see. Without knowing what software you're using, though, it's hard to say more

If this is the case, how do I change the it to TIC? I am using Shimadzu TQ series. I also put a photo on my previous reply. Thank you!

We already figured it out. I just change the settings in the "Fragment Table" and the chromatogram already appeared.

We already figured it out. I just change the settings in the "Fragment Table" and the chromatogram already appeared.

Awesome, I'm glad you figured that out because I have no experience at all with that brand and so could not have helped you out a whole lot, lol.