Ultra-high intra spectrum mass accuracy enables unambiguous identification of fragment reporter ions in isobaric multiplexed quantitative proteomics

摘要

1. Many ion signals in addition to the expected TMT reporter ions can be detected in this m/z range that entail the risk of distorted quantification. 2. The mass differences between TMT signals are measured within 0.1-0.2 mDa within a single tandem mass spectrum which allows the identification of reporter ions via their precise intra-spectrum mass differences. 3. The median mass error improves from 2.9 ppm to 0.5-0.8 ppm and all non-TMT ions are eliminated which leads to quantitative improvement. 4. The technique is generally applicable for any mass spectrometer and will be incorporated into the Proteome Discoverer software.