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Topic: CCS libraries and scoring for IM-MS (Read 206 times) previous topic - next topic

CCS libraries and scoring for IM-MS

Dear Hiroshi and MS-DIAL team,

I am using MS-DIAL 4.70 for LC-IM-QTOF data (Agilent and Waters, both operating in DIA mode) in a metabolomics/small molecules context. So far, I used CCS information "offline" for checking annotations using e.g. references from the CCS Compendium or in-house databases.
This was working fine for me, but I recently tried using the CCS text libraries distributed via your website.
MS-DIAL starts the process, but instead of running an analyis and showing the results, the process is interupted after a few seconds and I end up in the method window again (but without an error-message).

The text library was downloaded from the MS-DIAL website and was not changed.
Additionally, I tried different combinations of ticking "use CCS for scoring", "use CCS for filtering" and nothing in the IM-settings window, but this didn't change the observation.

Is this a known issue and if yes: how can I work around it?

I really appreciate your work and think that the CCS library option would be a great additional feature!

Additionally, it would be great to have the option to set tolerances for CCS in % rather than absolute values.
At least in the IM-MS context, tolerances are usually set in relative terms and tolerances can differ between different instrument classes (e.g. <+-1% for DT or <+- 2% for TW instruments).

Thank you very much in advance and best regards,

Max





Re: CCS libraries and scoring for IM-MS

Reply #1
Hi Max,
Are you working with Waters IMS data? I am really interested in how to process Water IMS data with MS-DIAL. Do you acquire your data with the UNIFI software?

Best,
QizhiSu

Re: CCS libraries and scoring for IM-MS

Reply #2
Dear QizhiSu,

The process was quite straight forward.
Data was acquired on a Synapt G2-S HDMS and using MassLynx software.
I converted .raw data to .ibf using MS-DIAL's ibf-converter and used .ibf files for the analysis.
Only calibration was performed using DriftScope.
I am not sure if this was the answer to your question though?

Best regards,

Max

Re: CCS libraries and scoring for IM-MS

Reply #3
Great, I thought .RAW format does not support IMS data. We are using VION with the UNIFI software. However, we cannot convert the IMS containing data into .RAW format. Maybe I can try again. Thanks for your tips.

Merry Christmas!
QizhiSu