bei Google ScholarTitelangaben
Desbenoit, Nicolas ; Walch, Axel ; Spengler, Bernhard ; Brunelle, Alain ; Römpp, Andreas:
Correlative mass spectrometry imaging, applying time-of-flight secondary ion mass spectrometry and atmospheric pressure matrix-assisted laser desorption/ionization to a single tissue section.
In: Rapid Communications in Mass Spectrometry.
Bd. 32
(2018)
Heft 2
.
- S. 159-166.
ISSN 1097-0231
DOI: https://doi.org/10.1002/rcm.8022
Abstract
Rationale
Mass spectrometry imaging (MSI) is a powerful tool for mapping the surface of a sample.Time‐of‐flight secondary ion mass spectrometry (TOF‐SIMS) and atmospheric pressurematrix‐assisted laser desorption/ionization (AP‐MALDI) offer complementary capabilities.Here, we present a workflow to apply both techniques to a single tissue section andcombine the resulting data for the example of human colon cancer tissue.
Methods
Following cryo‐sectioning, images were acquired using the high spatial resolution(1 μm pixel size) provided by TOF‐SIMS. The same section was then coated with a para‐nitroaniline matrix and images were acquired using AP‐MALDI coupled to an Orbitrapmass spectrometer, offering high mass resolution, high mass accuracy and tandem massspectrometry (MS/MS) capabilities. Datasets provided by both mass spectrometers wereconverted into the open and vendor‐independent imzML file format and processed withthe open‐source software MSiReader.
Results
The TOF‐SIMS and AP‐MALDI mass spectra show strong signals of fatty acids, cholesterol,phosphatidylcholine and sphingomyelin. We showed a high correlation between the fattyacid ions detected with TOF‐SIMS in negative ion mode and the phosphatidylcholineions detected with AP‐MALDI in positive ion mode using a similar setting for visualization.Histological staining on the same section allowed the identification of the anatomicalstructures and their correlation with the ion images.
Conclusions
This multimodal approach using two MSI platforms shows an excellent complementarityfor the localization and identification of lipids. The spatial resolution of bothsystems is at or close to cellular dimensions, and thus spatial correlation can onlybe obtained if the same tissue section is analyzed sequentially. Data processing basedon imzML allows a real correlation of the imaging datasets provided by these two technologiesand opens the way for a more complete molecular view of the anatomical structuresof biological tissues.