OpenLAB Custom Calculator

After running a GC sequence which generates data for blanks, standards, method blank and samples - I would like to subtract the area for a particular compound or timed group for the method blank from each of the samples.

I have been using the CC Editor to put custom calculations into the Injection Results tab of the sequence when viewing the data in data analysis (DA).  But I cannot seem to make it subtract one from the other. When you click on a particular injection in the sequence, it only gives you the data for that injection and does not give you the data for the method blank for exmple if you are viewing the sample injection?

Any help would be appreciated.

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  • Hello,

     

    I added tags to this post to increase visibility. 

     

    What revision of OpenLab CDS are you using? 

     

    Is there just going to be one blank run in your sequences or are there going to be multiple blank runs per sequence. If there are going to be multiple blank runs, then do you want to average the areas of your peak of interest across the injections and then subtract that value from the rest of the runs?

     

    And to clarify, you only want to take the area of one compound from the blank run to then subtract from other runs, correct? Or do you want to do this for all compounds? 

  • Hello ryoboyle,

    Thank you for the reply and for realising that I had posted  a duplicate by mistake - apologies.

    To answer your questions:

    • We are running OpenLAB CDS 2.3
    • There is only going to be one Method Blank per sequence
    • Yes, you are correct, I only want take the area for one specific compound/timed group and subtract that from all the sample injections only.

     

    I hope this helps, thanks

  • Hi,

    Thanks for these possible options.

    I will give them a go and hopefully they will work.

    I will definitely come back to you with some feedback after I have tried them early next week.

     

    Take care,

     

    Regards,

    Naweed

  • See below screenshots and give it a try to see if it works for your purposes. You will need to replace "Compound_A" in the CompoundA_BlankArea formula with the name of your compound.

     

     

    CorrectedArea should report Compound_Area for all compounds except for the identified compound in the CompoundA_BlankArea formula where it will report Compound_Area with the area from that compound in the blank injection subtracted. 

Reply
  • See below screenshots and give it a try to see if it works for your purposes. You will need to replace "Compound_A" in the CompoundA_BlankArea formula with the name of your compound.

     

     

    CorrectedArea should report Compound_Area for all compounds except for the identified compound in the CompoundA_BlankArea formula where it will report Compound_Area with the area from that compound in the blank injection subtracted. 

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