How do I create an RT to RI calibration?

Hi there!

I'm just starting to use masshunter, and I would like to use retention indices rather than retention times in my analyses, however, try as I may, I can't seem to find how I create the RT to RI calibration file that I am prompted for.

In my exhaustive Google searches, I can only find references to a file included on a demo disk, though nothing on how to actually create these files.

Does anyone have an example RT to RI calibration file that I may edit, or a means in the software to create one automatically?

Thank you all for your time,

James

  • Hi JamesRS,

    It sounds like you are looking for the Quant Tool "Retention Time Calibration," which is located in the Windows start menu under Agilent MassHunter Quantitative folder -> Quantitative Analysis Tools. 

    Additionally, there are some videos about using Refractive Index that are included on Quant media (either the USB thumb drive or the downloaded .UFD.) Specifically, the "Library - Retention Index - RI RT CAL map - Advanced" video goes over how to use the tool and create the calibration file. If you registered the software in Agilent.Subscribenet.com, you can re-download Quant to access these videos if they aren't already installed on the PC.  The videos are located at \Supplemental\MassHunter\Videos\Quant on the media. 

  • As @brittpeterson referenced, you will need to use the "RT Calibration" program to convert a set of results into a calibration file.
    To create the calibration file, you will need to create a batch in Masshunter Quant with just those samples and create a library with only the alkanes/calibration compounds. The batch and library will run automatically to create an output, there is no method involvement there. When creating our RT file, I found it best to create a custom library with only the relevant alkanes and verifying the matches myself in Quant before running through the program.

  • Hey msweber,

    can you possibly explain how you do this in detail? Do I have to create a library using the Library Editor or can I do it more quickly? Is it not possible to use the NIST database?

    Thank you in advance

  • It is absolutely possible using the NIST database, the reason I suggest creating a separate library is so you can control various parameters, mainly:

    • specific compound name
    • eliminate possibility of incorrect or undesired matches

    When you've created a custom library in library editor with 4 compounds with very clear peak and retention times, there is no chance of a "Dodecane" being identified as "Undecane"

    It is possible that you can do this more quickly using PCDL Manager, however I haven't had the opportunity to test that software. 

    I'm not sure which step you would like more in depth and it can easily become a multiple page post to detail each individual step in depth.

    Step by step:

    1. Create a custom library using Library Editor and a higher concentration sample for target spectra.
    2. Verify the accuracy of the library vs samples by trying to run through Quant with your new custom library as the only listing in "Library Search" of library method.
    3. Create batch file in Quant with the file(s).
    4. Use the "Retention Time Calibration" tool to create an RTC file.
  • The RTC file has been created so far. I would like to use the RT Calibration File at Masshunter Qualitative Analysis, but a CSV file is required there? What do I have to do to make a CSV from the RTC file?

  • The method editor should accept either a CSV or an RTC file

  • I am using v7 - this version requires a csv file
  • Hi ,

    From what I can find the RTC file is a CSV file. I believe this extension was created to help with file organization in later versions of MassHunter. So you should be able to change the extension and then use it in Qual.

    Another alternative, at least in newer versions of the RT Calibration tool, is to specify the extension as .csv when creating the calibration file. 

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