Comparison of Ion Mobility and Capillary Electrophoresis Mass Spectrometry techniques for cysteine connectivity identification of peptides bearing intra-molecular disulfide bonds

摘要

TIMS provides a higher resolution than TWIMS : TIMS reveals 2 conformations for the α-conotoxin used in this study; TIMS reveals more than one conformation for each apamin-based peptide. Main limitations of the TIMS : Not enough mobility calibrants; No trivial CID fragmentation. CE-MS is a valuable tool for the separation of a set of disulfide bond isomers (separation of the 3 apamin-based peptide). CE-MS allows 《in-solution》 characterization of disulfide isomers. In CE-MS, for the conotoxins, other pH values will be tested.