7 Replies Latest reply on Sep 25, 2017 3:08 PM by ryoboyle

    Why do samples added to the sequence table, while a run is in progress, disappear after the run finishes?

    spietrasiewicz

      I'm using OpenLAB CDS Chemstation Edition, on a 1290/6130 Single Quad LCMS.

       

      I am having an issue that if I start a run, and then add samples to the sequence table ("online edited"), then when the run finishes or errors out, those samples no longer show up in the sequence table, even if I save the sequence template after editing.  I've used chemstation for years and have never had this problem.

       

      Any insight would be great!

        • Re: Why do samples added to the sequence table, while a run is in progress, disappear after the run finishes?
          betrich

          In which data storage mode are you working?

          ChemStation introduces two data storage modes, to allow you to choose the data storage model that matches your workflow. These modes have influence of the sequence usage:

          • Unique Folder CreationON

          • Unique Folder CreationOFF

          Unique Folder CreationON for consistency of sample data uses sequences as “sequence templates” that can be used to run the acquisition multiple times; however, these templates are not used for reprocessing in Data Analysis. When the sequence template is run, a result set is created, containing all related files. If the sequence template is reused, a new result set is created for each reuse

          Unique Folder CreationOFF stores all data in one directory. The sequence *.s files are not used as sequence templates, so re-executing a sequence again

          might overwrite present data, if the data directory is not changed from the user.

          The available sequence/sequence templates (*.s) are visible in the ChemStation Explorer. For quick and easy navigation, you can add additional

          sequence/sequence template locations to the ChemStation Explorer selection tree using the Paths tab of the Preferences dialog box.

          • Re: Why do samples added to the sequence table, while a run is in progress, disappear after the run finishes?
            valentinrusu

            From my experience, this behavior is dependent on revision, and it leads me to believe you likely have Revision C.01.06 or C.01.07 of OpenLAB CDS ChemStation. Is that correct? If so, the behavior is an attempt at maintaining data integrity in the sequence file. A copy of that modified sequence file (.S) is located in the data results folder; this is likely located in C:\Chem32\1\Data\[your subdirectory]\[Container], where 1 is the instrument number and could be different, 'your subdirectory' is optional and 'Container' is your data results set. By default, the results set takes the form in Windows Explorer of folder named {Sequence file name} {YYYY-MM-DD-SS}. The reason the "master" sequence file (i.e., what I call the sequence file in the C:\Chem32\1\SEQUENCES folder) is unchanged with respect to its state before you started the sequence is for data integrity and compliance reasons. It appears that is not ideal for your workflow, but if you have one of the two revisions of ChemStation I think you do, that's the thinking behind it. If you have a different revision, we might be talking about a bug. To preserve the status of your changed sequence file, you can load that data results set in the Data Analysis view of ChemStation (location above), then click Sequence > Save Sequence Template As... and you'll have a usable copy of that sequence for future runs.

             

            I hope this helps!

            3 people found this helpful
            • Re: Why do samples added to the sequence table, while a run is in progress, disappear after the run finishes?
              ryoboyle

              I just wanted to follow-up to see if the previous reply in this thread answered your question. If so, please come back to the post and click the "Correct Answer" button on the response that helped so it will make the solution more visible. If you still need help, just let us know and we would be happy to continue working with you.

               

              I also added tags to this thread to make it easier to search.