How to exclude lockspray channel

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How to exclude lockspray channel lars debie  2023-09-29 04:18
 

In the data from a Waters Xevo G2-XS QTof with lockspray applied, the lockspray signal is stored as a separate channel. When the data is imported the data from the lockspray channel are included as datapoints. Since the compound of interested is not present at the point of lockspray, the peak or baseline is shown as zero when the lockspray was applied. This creates holes in the created chromatograms, see attachments. Is there a way to import only one channel and exclude the lockspray channel?

 
 
Brian Pratt responded:  2023-09-29 11:44

Hi Lars,

Normally Skyline ignores the lockmass channel automatically - there's probably something unusual about this data that we're not recognizing. Can you provide an example of this data, and a matching Skyline file (using Skyline's File|Share menu item)? You can upload to http://skyline.ms/files.url or someplace more private as you prefer.

Thanks for using the Skyline support board,

Brian Pratt

 
lars debie responded:  2023-10-02 02:25

Hi Brian,
I would prefer to send it more privately, can I send you a personal message/email with a link?

 
Brian Pratt responded:  2023-10-02 08:43

Certainly! I have sent you a private email.

 
Brian Pratt responded:  2023-10-03 09:06

Thank you for providing the data.

The logic that Skyline uses to decide which channel holds the lockspray data (channel 3, in this case, which is pretty standard) was confused by the presence of a 4th channel containing non-MS data. That channel was mistakenly identified as the lockspray channel.

We will improve that detection logic in our next Skyline-Daily, but for now you can work around this by making a copy of the .raw folder and removing the _FUNC004.* files from that before importing to Skyline.

 
lars debie responded:  2023-10-03 23:29

Thank you for your help, it now indeed ignores the lockspray channel.