Generating csv file from Qualitative Analysis of spectra for all m/z on time-based intervals?

Hi All,

Hoping someone more familiar with the software than I am can answer this. 

I am performing untargeted scans on samples to see difference in abundance and retention time of basically all m/z values present. (100-2000).

Obviously I can integrate peaks and export each individual MS compound list containing all m/z and abund. from under each peak, but is there a way to accomplish two variations of this process:

1. Generating MS compounds list for consecutive intervals rather than peaks. For example, instead of an output of all m/z values under a given peak, I would like to obtain a spectrum from 0.00 - 0.05 min, 0.00 - 0.010 min, and so on in small intervals. This is obviously time consuming using the range select with the cursor and extracting spectra that way, and also inconsistent with times. 

2. Generate csv report that contains all MS compound lists from all time intervals in one report? Currently with the peak-based integration I'm exporting a csv for each M/z compound list form EACH peak and combining together into a single file (combining ~60 files into one). 

Is there any way to accomplish these two tasks using the Qualitative software or should I look into exporting data and using third party? Thanks in advance. 

  • Hello  ,

    There is not a built-in tool or workflow in qual for doing an analysis like this. If your goal is to find potential compounds, for accurate mass data typically the Molecular Feature Extraction workflow can be used. For unit mass GC/MS data chromatographic deconvolution typically works well. For unit mass LC/MS there are no supported workflows, though depending on your version of Qual you may be able to manually enable MFE or deconvolution in the configuration, though these algorithms are not optimized for this type of data. The only other thing you could try for LCMS unit mass is to use Unknowns Analysis with chromatographic deconvolution. This is not an intended or tested workflow, but some customers have been able to get usable compound information for LCMS unit mass data.

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