Laserspray ionization-ion mobility spectrometry-mass spectrometry: baseline separation of isomeric amyloids without the use of solvents desorbed and Ionized directly from a surface.
The ability of laserspray ionization (LSI) to produce multiply charged ions by laser ablation from the solid state, directly from a surface, and at atmospheric pressure allows protein analysis on an ion mobility spectrometry (IMS)-mass spectrometry (MS) instrument (SYNAPT G2) having a mass-to-charge limit of 8000. The matrix, 2,5-dihydroxyacetophenone, lowers the thermal requirements for desolvation of matrix/analyte clusters to produce the highly charged LSI ions under gentle conditions to retain structural integrity of the proteins. Examples include cytochrome C and lysozyme. The solvent-free IMS gas-phase separation is used to baseline separate in the drift time dimension the isomeric solubility restricted β-amyloid (1-42) from the reversed (42-1). The LSI process is shown to be sufficiently soft to preserve structural integrity and permit separation according to the different shapes. These results suggest that LSI-IMS-MS potentially combines speed of analysis and imaging capability common to matrix-assisted laser desorption/ionization and multiple charging with the potential for structural analysis common to electrospray ionization.
Inutan
Ellen D
ED
Department of Chemistry, Wayne State University, Detroit, MI 48202, USA.
Trimpin
Sarah
S
D000682:Amyloid / Q000032:analysis* / Q000737:chemistry; D016229:Amyloid beta-Peptides / Q000032:analysis* / Q000737:chemistry / Q000145:classification; D006801:Humans; D007536:Isomerism; D010446:Peptide Fragments / Q000032:analysis* / Q000737:chemistry / Q000145:classification; D011487:Protein Conformation; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
D000682:Amyloid; D016229:Amyloid beta-Peptides; D010446:Peptide Fragments; C075222:amyloid beta-protein (1-42)