MALDI mass spectrometry imaging in plant and food lipidomics: advances, challenges, and future perspectives

Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) has established itself as a powerful analytical technique for spatially resolved lipidomics, offering unique insights into lipid distribution and metabolism directly within plant and food matrices. Recent methodological and technological advances have markedly improved the spatial resolution, sensitivity, and selectivity of MALDI-MSI, enabling high-definition mapping of complex lipidomes down to the cellular level. This review presents the current state of MALDI-MSI applications in plant and food lipidomics, with a focus on studies that have advanced our understanding of lipid heterogeneity, metabolic pathways, and spatial lipid organization. Special attention is given to the analytical challenges associated with lipid structural diversity, particularly isomerism and isobarism, and to the strategies developed to address these limitations. Emerging applications involving stable isotope labelling, advanced ion mobility spectrometry, and chemical derivatization are also discussed, highlighting their potential to enhance lipid identification and spatial localization. Finally, the review outlines future perspectives, emphasizing the integration of MALDI-MSI with complementary omics approaches and advanced computational tools to accelerate discoveries in plant biology, food quality assessment, and nutritional science.