Biomarkers in inflammatory bowel diseases: Current status and proteomics identification strategies

Figure 2 Two commonly used mass spectrometry techniques. A: Matrix-assisted laser desorption/surface-enhanced laser desorption/ionizatio time of flight mass spectrometry (MS), where the peptide or protein sample is dried on a target plate. Subsequently, a laser is used to evaporate the dried sample, and the generated gas phase ions are analyzed by the mass spectrometer; B: Liquid chromatography (LC)-electrospray ionization (ESI) MS, where the liquid peptide (or protein) sample is separated on a LC column, and sequentially eluted often over several hours. The eluted peptides are injected directly into the mass spectrometer by ESI and analyzed.