Peptidomic analysis of induced sputum: MALDI-TOF mass spectra before and after mesoporous silica beads (MSBs) processing. Utilization of MSBs makes it possible to markedly increase both peak number and signal intensity (AU: arbitrary units), referring to peptide profiles detectable in induced sputum (IS); m/z (mass-to-charge ratio) ranges from 800 to 7500 are reported. Average m/z values are indicated for selected peaks. The left side shows spectra obtained without MSB enrichment. Lower panels show MALDI-TOF profiles of the same IS sample, processed by different MSBs (MSB-A and MSB-D). Difference in surface functionalization (MSB-A versus MSB-D) gives rise to a fine modulation of the MALDI-TOF profiles.
