How can I put Relative RT on the chromatogram?!

How can I put relative RT on the chromatogram?!
Added from annotation it looks like are all 0.000; I don't know to establish reference peak.
My version of soft is

  • Hello,


    I added tags to this post to increase visibility.


    In order to calculate the relative retention time to be displayed as a peak annotation you will need to make sure that you follow the below steps. 


    1) In your Advanced Method Options (accessed by going to Method>Advanced), go to the Column/Performance tab and enter in the retention time of an unretained peak. Then check the 'Calculate performance parameters for this channel' checkbox.


    2) In the Peaks table you need to populate the 'Ref. ID #' column with the Peak # of the reference peak. For example, in the below screenshot Peak2 is identified as the reference peak for all other compounds. 



    Once those two things are done, process your result set and the relative retention time should be calculated. 


    Hopefully this helps. 

  • Hello!

    Thank you for the answer, it was helpful, but I realiase that I need in fact for Relative Retention Time (RRT=relative retention time for impurities with respect to principal peak ), that has another formula (RRT=RT of the impurity peak /RT of the principal peak).
    The question is : Can I bring (and eventually how ) new formulas that I need in soft in order to automatically calculate and also be written in the chromatogram report?! 
    Another example is for Area% that I want to calculate like described in European Pharmacopoeia for a specific product so another formula that Area% is generated from soft.

     Thank you alot!

  • Hello,


    Yes, it is possible to setup customer calculations using an Intelligent Report template in your OpenLab EZChrom software. Here is a link to the Intelligent Report Template Editor manual which can be a helpful reference when getting started with Intelligent Reporting: 

  • Hi, I Have the same question but for Openlab Chemstation Rev C.01.09.  

  • Hello,

    RRT is a standard calculation in C.01.09. In your calibration table, you to need to pick the relative retention time peaks (RTR.Rf), at least one must be selected for the calculation to be done. Then select which reference peak number is used as the RT reference for the other peaks, if more than one RTR.Rf peak was selected. This works like setting up IS or time reference peaks. I do not think RRT is part of any default IR tempaltes so you would need to add that column to any report tables. You can see the output below where the second peak is the RRT reference peak.

    Marty Adams

Was this helpful?