2P-21 PDF
LIPID VISUALISATION AND IDENTIFICATION THROUGH COLLISION CROSS SECTION AIDED CORRELATION OF MALDI IMAGING AND MS/MS FRAGMENTATION DATA SETS
Mass spectrometry imaging (MSI) is rapidly becoming an established technique within lipidomics research. Using MSI, a broad range and number of species can be visualised within a tissue section. However, subsequent identification can be challenging due to the large number of isobaric or near isobaric species.
Lipids can be identified by subsequently extracting them from the same, or a consecutive, tissue section and performing MS/MS. However, when correlating the datasets, identifications can become obfuscated due to lack of certainty that the lipids extracted and identified, relate to the m/z peaks seen in the imaging data, especially when relying on accurate mass alone as the identification is not being performed in-situ.
Here, we demonstrate the use of ion mobility to differentiate ions and calculate collision cross sections (CCS). This is utilised along with accurate mass to add confidence to the correlation between the MALDI imaging and extracted lipids datasets and the subsequent identifications by MS/MS.