Converting to a Singly Charged Spectrum (Mariner Data Only)

5.10Converting to a Singly Charged Spectrum (Mariner Data Only)

NOTE: Single-charge conversion is not supported for

Mariner DAD data.

Description The Single-Charge Conversion function generates a theoretical, centroided, singly charged spectrum. This function uses isotopic spacing in detected spectral peaks to generate the theoretical spectrum.

For example, if you use this function on a spectrum that includes +3 peaks, the software multiplies each mass by 3 and removes the mass of two extra protons. The resulting spectrum contains theoretical +1 species.

If more than one charge state is present, each charge state is converted appropriately, and the total range of the converted spectrum is approximately 1.2 times the m/z of the highest m/z present.

Requirements Use this function only on isotopically resolved data that is labeled with the correct charge state. Peaks with low signal-to-noise ratios may be labeled with incorrect charge states. Set peak detection thresholds to disregard these peaks before converting the spectrum.

If you use this function on a spectrum that is not correctly labeled, the resulting spectrum may contain charge states other than 1.

Converting To convert a multiply charged spectrum to a singly charged spectrum:

1.Display the spectrum trace of interest.

2.Examine the spectrum. Make sure peaks are labeled with

the correct charge state, and that no noise peaks are

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labeled with a charge state. Adjust peak detection

parameters as needed.

 

Data Explorer™ Software User’s Guide

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