| Title: | "Matrix assisted ionization: new aromatic and nonaromatic matrix compounds producing multiply charged lipid, peptide, and protein ions in the positive and negative mode observed directly from surfaces" |
| Author(s): | Li J; Inutan ED; Wang B; Lietz CB; Green DR; Manly CD; Richards AL; Marshall DD; Lingenfelter S; Ren Y; Trimpin S; |
| Address: | "Department of Chemistry, Wayne State University, Detroit, MI 48202, USA" |
| DOI: | 10.1007/s13361-012-0413-z |
| ISSN/ISBN: | 1879-1123 (Electronic) 1044-0305 (Linking) |
| Abstract: | "Matrix assisted inlet ionization (MAII) is a method in which a matrix:analyte mixture produces mass spectra nearly identical to electrospray ionization without the application of a voltage or the use of a laser as is required in laserspray ionization (LSI), a subset of MAII. In MAII, the sample is introduced by, for example, tapping particles of dried matrix:analyte into the inlet of the mass spectrometer and, therefore, permits the study of conditions pertinent to the formation of multiply charged ions without the need of absorption at a laser wavelength. Crucial for the production of highly charged ions are desolvation conditions to remove matrix molecules from charged matrix:analyte clusters. Important factors affecting desolvation include heat, vacuum, collisions with gases and surfaces, and even radio frequency fields. Other parameters affecting multiply charged ion production is sample preparation, including pH and solvent composition. Here, findings from over 100 compounds found to produce multiply charged analyte ions using MAII with the inlet tube set at 450 degrees C are presented. Of the compounds tested, many have -OH or -NH(2) functionality, but several have neither (e.g., anthracene), nor aromaticity or conjugation. Binary matrices are shown to be applicable for LSI and solvent-free sample preparation can be applied to solubility restricted compounds, and matrix compounds too volatile to allow drying from common solvents. Our findings suggest that the physical properties of the matrix such as its morphology after evaporation of the solvent, its propensity to evaporate/sublime, and its acidity are more important than its structure and functional groups" |
| Keywords: | "Animals Cattle Humans Hydrogen-Ion Concentration Ions/chemistry Laboratory Chemicals/chemistry Lipids/chemistry Models, Molecular Organic Chemicals/chemistry Peptides/chemistry Proteins/*chemistry Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ioniz;" |
| Notes: | "MedlineLi, Jing Inutan, Ellen D Wang, Beixi Lietz, Christopher B Green, Daniel R Manly, Cory D Richards, Alicia L Marshall, Darrell D Lingenfelter, Steven Ren, Yue Trimpin, Sarah eng Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. 2012/08/17 J Am Soc Mass Spectrom. 2012 Oct; 23(10):1625-43. doi: 10.1007/s13361-012-0413-z. Epub 2012 Aug 16" |
