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Title: Sublimation Driven Ionization for Use in Mass Spectrometry: Mechanistic Implications
Sublimation has been known at least since the middle ages. This process is frequently taught in schools through use of phase diagrams. Astonishingly, such a well-known process appears to still harbor secrets. Under conditions in which compound sublimation occurs, gas-phase ions are frequently detected using mass spectrometry. This was exploited in matrix-assisted ionization in vacuum vMAI) by adding analyte to subliming compounds used as matrices. Good vMAI matrices were those that ionize the added analyte with high sensitivity, but even matrices that fail this test often produce ions of likely matrix impurities suggesting that they may be good matrices for some compound types. We also show that binary matrices may be manipulated to provide desired properties such as fast analyses and improved sensitivity. These results imply that sublimation in some cases is more complicated than just molecules leaving a surface and that understanding the physical force responsible, and how the nonvolatile compound becomes charged, could lead to improved ionization efficiency for mass spectrometry. Here we provide insights into this process and an explanation of why this unexpected phenomenon has not previously been reported.  more » « less
Award ID(s):
1913787
NSF-PAR ID:
10202767
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Journal of the American Society for Mass Spectrometry
ISSN:
1044-0305
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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