Standard curve regression line not showing

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Standard curve regression line not showing stefan broeer  2025-06-05 21:11
 

I quantify analytes with heavy isotope standards. Sometimes there is an odd standard where the ratio to heavy could not be calculated.
Then skyline does not show the regression line. To improve the fit standards can be excluded but for that they have to show up on the graph.
How can you delete standards that could not be calculated (NaN or similar) or show the regression line for the remaining standards?

 
 
Nick Shulman responded:  2025-06-05 21:51
You can also use the Results Grid or Document Grid to exclude Standards.
The easiest thing would probably be to use the Results Grid and customize a report and add the "Exclude from Calibration" column to the report.
It would then be straightforward for you to find the NaN values in the grid and use the checkboxes in the "Exclude from Calibration" column to exclude particular replicates.
You can learn about the Document Grid in the Custom Reports tutorial:
https://skyline.ms/wiki/home/software/Skyline/page.view?name=tutorial_custom_reports

The Results Grid is similar to the Document Grid, except that the Results Grid shows only the subset of rows related to whatever is currently selected in the Targets tree. The Results Grid would probably be easier for quickly finding the values which are preventing the calibration curve from being displayed.

I can't think of a straightforward way for Skyline to plot these infinite values on the Calibration Curve to give you something to click on.

It might be helpful if you could send us your Skyline document.
In Skyline you can use the menu item:
File > Share
to create a .zip file containing your Skyline document and supporting files including extracted chromatograms.

Files which are less than 50MB can be attached to these support requests. You can always upload larger files here:
https://skyline.ms/files.url

We might be able to come up with a better solution for this. In the meantime, the "Exclude from Calibration" in the Results Grid or the Document Grid might work for you.
-- Nick
 
stefan broeer responded:  2025-06-10 00:06
Thanks, I had forgotten about adding "Exclude from calibration" to the report.
It all worked well after taking out the NaN's.
Skyline is a great piece of software!