Performing 2D–1D–2D Mass Spectrometry Imaging Using Strings

AbstractCorticosteroids as budesonide can be effective in reducing topic inflammation processes in different organs. Therapeutic use of budesonide in respiratory diseases, like asthma, chronic obstructive pulmonary disease, and allergic rhinitis is well known. However, the pulmonary distribution of budesonide is not well understood, mainly due to the difficulties in tracing the molecule in lung samples without the addition of a label. In this paper, we present a matrix-assisted laser desorption/ionization mass spectrometry imaging protocol that can be used to visualize the pulmonary distribution of budesonide administered to a surfactant-depleted adult rabbit. Considering that budesonide is not easily ionized by MALDI, we developed an on-tissue derivatization method with Girard’s reagent P followed by ferulic acid deposition as MALDI matrix. Interestingly, this sample preparation protocol results as a very effective strategy to raise the sensitivity towards not only budesonide but also other corticosteroids, allowing us to track its distribution and quantify the drug inside lung samples. Graphical abstract

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Shotgun lipidomics and mass spectrometry imaging unveil diversity and dynamics in Gammarus fossarum lipid composition

iScience ◽

10.1016/j.isci.2021.102115 ◽

2021 ◽

Vol 24 (2) ◽

pp. 102115

Author(s):

Tingting Fu ◽

Oskar Knittelfelder ◽

Olivier Geffard ◽

Yohann Clément ◽

Eric Testet ◽

...

Keyword(s):

Mass Spectrometry ◽

Lipid Composition ◽

Mass Spectrometry Imaging ◽

Shotgun Lipidomics ◽

Gammarus Fossarum

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Diagnosis of Agglomeration and Crystallinity of Active Pharmaceutical Ingredients in Over the Counter Headache Medication by Electrospray Laser Desorption Ionization Mass Spectrometry Imaging

Molecules ◽

10.3390/molecules26030610 ◽

2021 ◽

Vol 26 (3) ◽

pp. 610

Author(s):

Mariann Inga Van Meter ◽

Salah M. Khan ◽

Brynne V. Taulbee-Cotton ◽

Nathan H. Dimmitt ◽

Nathan D. Hubbard ◽

...

Keyword(s):

Mass Spectrometry ◽

Mass Spectrometry Imaging ◽

Laser Desorption ◽

Ionization Mass Spectrometry ◽

Ionization Mass ◽

Active Pharmaceutical Ingredients ◽

Laser Desorption Ionization ◽

Over The Counter ◽

Pharmaceutical Ingredients ◽

Desorption Ionization

Agglomeration of active pharmaceutical ingredients (API) in tablets can lead to decreased bioavailability in some enabling formulations. In a previous study, we determined that crystalline APIs can be detected as agglomeration in tablets formulated with amorphous acetaminophen tablets. Multiple method advancements are presented to better resolve agglomeration caused by crystallinity in standard tablets. In this study, we also evaluate three “budget” over-the-counter headache medications (subsequently labeled as brands A, B, and C) for agglomeration of the three APIs in the formulation: Acetaminophen, aspirin, and caffeine. Electrospray laser desorption ionization mass spectrometry imaging (ELDI-MSI) was used to diagnose agglomeration in the tablets by creating molecular images and observing the spatial distributions of the APIs. Brand A had virtually no agglomeration or clustering of the active ingredients. Brand B had extensive clustering of aspirin and caffeine, but acetaminophen was observed in near equal abundance across the tablet. Brand C also had extensive clustering of aspirin and caffeine, and minor clustering of acetaminophen. These results show that agglomeration with active ingredients in over-the-counter tablets can be simultaneously detected using ELDI-MS imaging.

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Mass spectrometry imaging of L-[ring-13C6]-labeled phenylalanine and tyrosine kinetics in non-small cell lung carcinoma

Cancer & Metabolism ◽

10.1186/s40170-021-00262-9 ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Jianhua Cao ◽

Benjamin Balluff ◽

Martijn Arts ◽

Ludwig J. Dubois ◽

Luc J. C. van Loon ◽

...

Keyword(s):

Mass Spectrometry ◽

Amino Acids ◽

Amino Acid ◽

Mass Spectrometry Imaging ◽

Tumor Tissue ◽

Small Cell Lung Carcinoma ◽

Small Cell ◽

Small Cell Lung ◽

Tracer Injection ◽

Cell Lung Carcinoma

Abstract Background Metabolic reprogramming is a common phenomenon in tumorigenesis and tumor progression. Amino acids are important mediators in cancer metabolism, and their kinetics in tumor tissue are far from being understood completely. Mass spectrometry imaging is capable to spatiotemporally trace important endogenous metabolites in biological tissue specimens. In this research, we studied L-[ring-13C6]-labeled phenylalanine and tyrosine kinetics in a human non-small cell lung carcinoma (NSCLC) xenografted mouse model using matrix-assisted laser desorption/ionization Fourier-transform ion cyclotron resonance mass spectrometry imaging (MALDI-FTICR-MSI). Methods We investigated the L-[ring-13C6]-Phenylalanine (13C6-Phe) and L-[ring-13C6]-Tyrosine (13C6-Tyr) kinetics at 10 min (n = 4), 30 min (n = 3), and 60 min (n = 4) after tracer injection and sham-treated group (n = 3) at 10 min in mouse-xenograft lung tumor tissues by MALDI-FTICR-MSI. Results The dynamic changes in the spatial distributions of 19 out of 20 standard amino acids are observed in the tumor tissue. The highest abundance of 13C6-Phe was detected in tumor tissue at 10 min after tracer injection and decreased progressively over time. The overall enrichment of 13C6-Tyr showed a delayed temporal trend compared to 13C6-Phe in tumor caused by the Phe-to-Tyr conversion process. Specifically, 13C6-Phe and 13C6-Tyr showed higher abundances in viable tumor regions compared to non-viable regions. Conclusions We demonstrated the spatiotemporal intra-tumoral distribution of the essential aromatic amino acid 13C6-Phe and its de-novo synthesized metabolite 13C6-Tyr by MALDI-FTICR-MSI. Our results explore for the first time local phenylalanine metabolism in the context of cancer tissue morphology. This opens a new way to understand amino acid metabolism within the tumor and its microenvironment.

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