Matrix pre-coated MALDI MS targets for small molecule imaging in tissues.

Area of Science:

• Analytical Chemistry
• Biomedical Imaging
• Mass Spectrometry

Background:

• Matrix-assisted laser desorption/ionization (MALDI) tissue imaging is a powerful technique for spatial molecular analysis.
• Traditional MALDI sample preparation can be time-consuming and may involve solvents that risk analyte delocalization.

Purpose of the Study:

• To develop a simplified and efficient sample preparation method for MALDI tissue imaging.
• To enable the analysis of low molecular weight compounds, including lipids, peptides, and pharmaceuticals, in tissue sections.

Main Methods:

• Development of matrix pre-coated MALDI targets with homogenous, uniformly sized matrix crystals (1-2 μm).
• Direct transfer of tissue sections onto pre-coated targets, eliminating the need for manual matrix application and solvents.
• Application of the method for MALDI tissue imaging of lipids, peptides, and pharmaceuticals in various tissue types.

Main Results:

• The pre-coated targets provide a uniform matrix layer, crucial for reproducible MALDI analysis.
• The solvent-free transfer method prevents analyte delocalization, preserving spatial molecular information.
• Successful imaging of lipids, peptides, and pharmaceuticals was demonstrated, showcasing the method's versatility.

Conclusions:

• Matrix pre-coated MALDI targets offer a fast, easy, and effective sample preparation solution for tissue imaging.
• This approach enhances the reliability and accessibility of MALDI tissue imaging for diverse analytes.
• The method is suitable for routine analysis and discovery of low molecular weight compounds in biological tissues.