Figure 2: ESI+ extracted ion chromatogram of the masses for N6-acetyllysine and N-acetylglutamine from a human serum extract from the HRAM instrument (A) and from the UMR instrument (B). Precise masses and mass windows used are labeled on each panel. The added mass resolution and accuracy permitted N6-acetyllysine to be fully resolved from N-acetylglutamine in HRAM data streams, thus permitting the accurate detection of both molecules, which was not possible in the UMR data stream.