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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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This content will become publicly available on December 4, 2025
Quantitative Analysis of Drugs in a Mimetic Tissue Model Using Nano-DESI on a Triple Quadrupole Mass Spectrometer
Mass spectrometry is a powerful analytical technique used at every stage of the pharmaceutical research process. A specialized subset of this technique, mass spectrometry imaging (MSI) has emerged as an important technique for determining the spatial distribution of drugs in biological samples. Despite the importance of MSI, its quantitative capabilities are still limited due to the complexity of biological samples and the lack of separation prior to analysis. This makes the simultaneous quantification and visualization of analytes challenging. Several techniques have been developed to address this challenge and enable quantitative MSI. One of these techniques is the mimetic tissue model, which involves the incorporation of an analyte of interest into tissue homogenates at several concentrations. A calibration curve that accounts for signal suppression by the complex biological matrix is then created by measuring the signal of the analyte in the series of tissue homogenates. Herein, we use the mimetic tissue model on a triple quadrupole mass spectrometer (QqQ) in multiple reaction monitoring (MRM) mode to demonstrate the quantitative abilities of nanospray desorption electrospray ionization (nano-DESI) and compare these results with those obtained using atmospheric pressure matrix-assisted laser desorption/ionization (AP-MALDI). For the tested compounds, our findings indicate that nano-DESI achieves lower standard deviations than AP-MALDI which contributes to nano-DESI also achieving lower limits of detection (LOD) for the analytes studied. Additionally, we discuss the limitations of the mimetic tissue model in the quantification of certain analytes and the challenges involved with the implementation of the model.
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- Award ID(s):
- 2108729
- PAR ID:
- 10587729
- Publisher / Repository:
- ACS
- Date Published:
- Journal Name:
- Journal of the American Society for Mass Spectrometry
- Volume:
- 35
- Issue:
- 12
- ISSN:
- 1044-0305
- Page Range / eLocation ID:
- 3170 to 3177
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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