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Abstract Mass spectrometry imaging (MSI) of volatile metabolites is challenging, especially in matrix‐assisted laser desorption/ionization (MALDI). Most MALDI ion sources operate in vacuum, which leads to the vaporization of volatile metabolites during analysis. In addition, tissue samples are often dried during sample preparation, leading to the loss of volatile metabolites even for other MSI techniques. On‐tissue chemical derivatization can dramatically reduce the volatility of analytes. Herein, a derivatization method is proposed utilizing N,N,N‐trimethyl‐2‐(piperazin‐1‐yl)ethan‐1‐aminium iodide to chemically modify short‐chain fatty acids in chicken cecum, ileum, and jejunum tissue sections before sample preparation for MSI visualization.
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Ambient ionization mass spectrometry: real-time, proximal sample processing and ionization
The definition of ambient ionization is updated from “no sample preparation” to sample preparation proximal and in real time with the ionization and analysis step. We differentiate between ambient ionization methods and the direct and hyphenated techniques. Ambient ionization has been reviewed many times and we summarise some of the approaches that reviews have taken to categorize the many ambient ionization methods. Due to the large number of permutations, frequent redundancy and complexity of the 80+ techniques developed so far, none of the review classifications is successful in classifying all the ambient ionization methods based on the chosen scheme. Likewise our classification based on major sample preparation method also fails at finding a good category for every method, but it does highlight the central role that real-time, proximal sample preparation plays in ambient analysis.
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- Award ID(s):
- 1508626
- PAR ID:
- 10067759
- Date Published:
- Journal Name:
- Analytical Methods
- Volume:
- 9
- Issue:
- 34
- ISSN:
- 1759-9660
- Page Range / eLocation ID:
- 4896 to 4907
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/c7ay00948h
