I'm reanalyzing some Bruker TIMS-TOF PASEF data from the MS Dial 4 nature biotech paper in 2020 to get familiar with processing ion mobility data. There are many cases where two identical lipids at same retention time were reported. One has CCS value while the other has "-1" as CCS. See picture below. Just wondering which one I should trust or they are all real? And how I can filter if one of them needs to be removed.
In the recently published paper, 'MS-DIAL 4: accelerating lipidomics using an MS/MS, CCS, and retention time atlas', 117 lipid subclasses were made available for lipid identification. NAGlySer is one of them and it's a good news for me since it's quite abundant in the bacteria I study. The problem is I can't seem to find it in 'identification' tab. Any suggestion on how to find and select it?