Eliminating Artifacts in Electrospray Deconvolution with a SoftMax Function

  • Michael T. MartyEmail author
Application Note


UniDec provides a rapid and robust approach to deconvolving electrospray mass spectra into their corresponding mass and charge components. However, the UniDec algorithm can produce artifacts depending on the quality and complexity of the data. Here, a SoftMax function is applied to the charge state distribution of each data point, which pushes the algorithm towards assigning each data point to one primary charge state. As shown for several data sets of increasing complexity, the SoftMax function significantly reduces deconvolution artifacts, even for data with overlapping charge states.


Mass spectrometry Electrospray Native MS Intact mass Deconvolution 



The author thanks William Resager, Eamonn Reading, and Georg Hochberg for contributing spectra. This work was funded by the Bisgrove Scholar Award from Science Foundation Arizona, the American Society for Mass Spectrometry Research Award, the National Science Foundation (CHE-1845230), and the National Institute of General Medical Sciences and National Institutes of Health (R35 GM128624) to M.T.M. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Supplementary material

13361_2019_2286_MOESM1_ESM.pdf (276 kb)
ESM 1 (PDF 276 kb)


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Copyright information

© American Society for Mass Spectrometry 2019

Authors and Affiliations

  1. 1.Department of Chemistry and BiochemistryUniversity of ArizonaTucsonUSA

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