High-resolution IMS-MS can supplement or replace LC for the detection and identification of isomeric sugar phosphates.
Metabolomics researchers frequently face extremely complex and challenging samples. The field is dominated by LC-MS based approaches; yet, chemical diversity of the samples makes the efficient separation and confident detection of a large number of metabolites extremely challenging. High resolution ion mobility spectrometry-mass spectrometry is especially powerful for the separation of isomers. IMS-MS can also be coupled to LC and is therefore an attractive technique to boost separation power and consequently increase the number of detected metabolites.
Sugar phosphates are critically involved in important metabolic pathways such as glycolysis or the pentose phosphate pathway. Due to their isomeric nature, many of them cannot be distinguished using LC or MS/MS. Nonetheless, the concentration of these sugar phosphates can provide crucial insights into a system’s metabolic state.
Using the TOFWERK IMS-TOF, we show here that high resolution IMS-MS, either as a stand-alone technique or coupled to LC, improves the identification of isomeric sugar phosphates. IMS drift times are directly linked to collision cross sections and can therefore be used as molecular identifiers.