Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI MSI) for in situ analysis of endogenous small molecules in biological samples

Endogenous small molecules play important roles in biological processes and are closely related to the occurrence and development of many diseases. Profiling of spatial distribution of small molecules is indispensable for understanding their biological roles and elucidating disease mechanisms. Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI), a robust tool for in situ analysis of various molecules simultaneously with high sensitivity in a single run, has been more and more widely used in biomedical field. This paper first gave an introduction of small molecules and MSI. Then critical issues in the workflow of MALDI MSI, including sample collection, matrix selection and disposition, and instrument were detailed described. On this basis, applications of MALDI MSI in bio-logical field including biomarker discovery, disease mechanism investigation, cell metabolism, host -micro interaction, lipids isomeric resolution etc., were summarized. Finally, the challenges and the perspectives of MALDI MSI of small molecules are concluded and proposed. (c) 2022 Elsevier B.V. All rights reserved.

Automated summary

This paper provides an overview of the importance of endogenous small molecules in biological processes and their relevance to various diseases. It highlights the use of matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) as a powerful tool for analyzing small molecules in situ. The paper discusses the workflow, applications, challenges, and future directions of MALDI-MSI for small molecule analysis.