TOF/Qual Question

Hello.  As a novice with MassHunter Qualitative Analysis Workflow/Navigator, I could use some help.  I need to measure relative signal intensity for one small molecule in 3 samples.  The thing that makes this circumstance challenging is that I expect to have a total of 1000 sets of 3 samples at one time, each containing one small molecule.  I have access to a 6230 TOF as well as numerous 6410 to 6495 triple quad instruments.  Due to time and resource constraints, I cannot tune all 1000 compounds.  I can think of two different ways to accomplish this task.

  • Create 1000 SRM acquisition methods each monitoring one parent mass
  • Collect full scan data and extract the parent ions of interest for peak integration

Unless there's a better option, I'm leaning toward the second option along with use of the TOF to help improve selectivity.  Is there a reasonably elegant way to do this in Qual?  I spent time looking at Workflow's Target/Suspect screening and I think it might work, but it's not an ideal solution since I know the identity of the compound to measure within each sample.  Any help you could give me to point my compass in the right direction would be greatly appreciated!

  • Hello  ,

    When you say relative signal intensity, do you mean to one of the three runs, or some other intensity? Or do you just need to report the area counts of a given compound in each run?

    Also, you mention 

    "I spent time looking at Workflow's Target/Suspect screening and I think it might work, but it's not an ideal solution since I know the identity of the compound to measure within each sample."

    If you do have the formula for the compound, then compound screening would be the best workflow to utilize for TOF data. Did you mean to say that you don't know the identity of the compound? 

  • Thanks, Howard.  Here's an example injection sequence.  Each sample will contain one compound.

    • Compound #1, Sample #1
    • Compound #1, Sample #2
    • Compound #1, Sample #3
    • Compound #2, Sample #1
    • Compound #2, Sample #2
    • Compound #2, Sample #3
    • ...
    • Compound #1000, Sample #1
    • Compound #1000, Sample #2
    • Compound #1000, Sample #3

    I will know the identity (and molecular formula) of each compound in each sample and will need to measure that compound's response.  When I mentioned needing to measure relative response, I meant that after measuring response in each sample, I will then need to compare intensities for sample #1 to sample #2 and sample #3 to evaluate changes.

    Hopefully this helps.  Let me know if you have any questions and thanks for your help!

  • Hello  ,

    If you know the formula, then using Find by Formula would work for getting the results in Qual. You could set up your worklist to enter the formula there by adding the MFC column and have it available when processing. Though there is no way in Qual to automatically compare the response of the three runs. For that you would have to move to Quant. You can initiate Quant from Qual after the compound is found to set up a method, but only one file will be added to the batch. You would need to add the other two samples, assign one run as a standard with a concentration of 1 or 100, and then process to get the relative responses.

    It may be simpler to start with Quant, but I'm not aware of any way to automate the method setup for accurate mass data. You could at least set up one as your runs as a standard, set up the batch, manually add the m/z of interest, and then process.

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