70% in-source fragments? The data tells a different story!
A recent commentary by Giera et al. (link) sparked a discussion about in-source fragmentation (ISF). The authors claimed that “ISF could account for over 70% of the peaks observed in typical LC–MS/MS metabolomic datasets”. This claim, echoed by other outlets, even went as far as suggesting that “over 70% of the dark metabolome could be an experimental artefact” (link). Many metabolomics practitioners reacted with…