How do I view UV spectrum data in the MassHunter Quantitative software

Hello Ajhumphrey ,

It is possible to view the UV spectrum in quant. While it is easier to work with UV only data in the GC or 2D version of quant, you will need to use one of the MS versions of quant to have access to the Show/Hide Spectrum option in the Compound Information window. If there is spectral information and your signal is defined to be a DAD signal, then the spectrum should be extracted. 

Thank you for your help.  We had been using the Masshunter for GC version and the extract button was not an option.  When I opened it in Masshunter for QQQ I was able to extract the UV spectrum.  Now I just need to figure out if I can average the UV spectrum across the peaks and get the UV to look closer to a reference.  

Ajhumphrey ,

By default, the spectrum is extracted as an average across the peak. The time range used is shown it the title for the spectrum. You can change this in the method editor under Advanced Tasks->Spectrum Extraction Setup. Spectrum Extraction Window can be set to Average or Apex.

You can add the Spectrum Peak Height % Threshold column and change the setting here to only use points in the chromatogram that are above the specified percentage of the peak height. 

Is there a way label the UV spectra with wavelength maxima?

 kklontz ,

There are limited options available for working with UV spectrum. In qual you can, of course, export to CSV and determine the maxima. There is not a way to label the UV spectrum peaks automatically in qual, though you can enable the annotation tool and if you select the highest point and choose to add an annotation it will list the X coordinates in nm. 

The only option I can find in quant to see the maxima is almost certainly not intended, but it does appear to work. If you right click on the UV spectrum and choose Search Library... and then Cancel the library selection you will be presented with a 'centroided' version of the UV spectrum. 

It appears to label each local maxima. You can also zoom in and each 'peak' will be labeled. 

 kklontz ,

There are limited options available for working with UV spectrum. In qual you can, of course, export to CSV and determine the maxima. There is not a way to label the UV spectrum peaks automatically in qual, though you can enable the annotation tool and if you select the highest point and choose to add an annotation it will list the X coordinates in nm. 

The only option I can find in quant to see the maxima is almost certainly not intended, but it does appear to work. If you right click on the UV spectrum and choose Search Library... and then Cancel the library selection you will be presented with a 'centroided' version of the UV spectrum. 

It appears to label each local maxima. You can also zoom in and each 'peak' will be labeled. 

Great, thank you for your help.  I think we will use this.