Ambient Single-Cell Analysis and Native Tissue Imaging Using Laser-Ablation Electrospray Ionization Mass Spectrometry...

Area of Science:

• Analytical Chemistry
• Biochemistry
• Biophysics

Background:

• Ambient ionization mass spectrometry methods are advancing metabolomics.
• Laser-ablation electrospray ionization mass spectrometry (LAESI-MS) offers minimal sample preparation and in situ analysis using endogenous water.
• Spatially resolved metabolomics requires high-resolution imaging techniques.

Purpose of the Study:

• To detail the use of a novel "LAESI microscope" source for spatially resolved mass spectrometry (MS) analysis.
• To demonstrate high-resolution MS imaging (MSI) of biological tissues.
• To showcase the capabilities of LAESI-MS for high-mass-resolution and high-mass-accuracy metabolomics.

Main Methods:

• Utilized a "LAESI microscope" source with a long-working-distance reflective objective for sample visualization and a focused laser beam.
• Performed spatially resolved MS analysis on 200 single cells of Allium cepa (red onion).
• Conducted high-spatial-resolution MS imaging of Fittonia argyroneura (nerve plant) tissue.
• Coupled the LAESI source to a Fourier transform mass spectrometer for sensitive detection.

Main Results:

• Achieved high spatial resolution in MS analysis of single cells and tissue imaging.
• Demonstrated the capability of the LAESI microscope for detailed metabolomic profiling.
• Obtained high-mass-resolution and high-mass-accuracy data, crucial for confident metabolite identification.

Conclusions:

• The "LAESI microscope" source is a powerful tool for spatially resolved metabolomics.
• This approach enables detailed analysis of cellular and tissue metabolomes at high resolution.
• LAESI-MS has significant potential to advance the field of metabolomics and related life sciences.