Members of the genus Phytobacter, part of the Enterobacteriaceae, represent an emerging clinical threat. Standard identification methodologies often f…

Mass spectrometry imaging enables spatially resolved, label-free detection of metabolites in tissue and culture systems, providing insight into their metabolic landscape and spatial distribution. However, conventional approaches often lack the spatial resolution and specificity needed to investigate metabolic heterogeneity at the single cell level, particularly in physiologically relevant models. Here, we present a single cell ambient mass spectrometry imaging platform, enabling direct chemical mapping of metabolites at 10 um resolution. This method integrates cell labelling, high resolution microscopy and APMALDI Orbitrap mass spectrometry imaging to achieve cell type specific metabolite profiling. To demonstrate its application, we applied this approach to glioblastoma (GBM), an aggressive adult brain tumour characterised by cellular heterogeneity, metabolic adaptation, and infiltrative growth within the tumour microenvironment. A co culture model combining patient-derived glioblastoma invasive-margin cells with human cortical astrocytes was used to recapitulate the invasive niche. Distinct metabolic signatures emerged upon glioblastoma and astrocyte interaction, involving pathways related to nucleotide metabolism, phospholipid and sphingolipid turnover, and tryptophan and tyrosine metabolism. These findings suggest cell-type-specific metabolic activity and potential intercellular metabolic interplay. Overall, this workflow offers a broadly accessible and robust approach for investigating metabolic heterogeneity at cellular resolution, enabling insights into metabolic interactions of heterogenous cell types in both disease and non disease settings.

Matrix-assisted laser desorption/ionisation mass spectrometry imaging (MALDI-MSI) is a powerful technique for studying lipid distribution in carotid plaques, key to understanding atherosclerosis. This study aimed to improve sample preparation for MALDI-MSI-based spatial lipidomics of carotid plaques by improving both matrix application and tissue handling. Human carotid plaques were collected from endarterectomy patients with ethical approval and sectioned at 10 um thickness for MALDI-MSI. We compared eight sample preparation methods, including hydroxypropyl methylcellulose-polyvinylpyrrolidone (HPMC-PVP) embedding media and Cryofilm-type IMS to provide support and maintain tissue structural integrity during sectioning. Methods were assessed for signal intensity, lipid diffusion, lipid coverage, tissue morphology, and image co-registration which each criterion scored from 1-3. Cryofilm-based methods scored highest for preserving tissue morphology and minimising folding artifacts (2.9-3.0) but were limited in co-registration (2.0) due to reliance on adjacent sections. Sublimation methods generally produced greater lipid coverage with reduced lateral diffusion, while automated sprayer methods scored higher in signal intensity/sensitivity (3.0) but had increased lipid delocalisation, particularly for highly hydrophobic species such as triacylglycerols and sterols. The results highlight clear trade-offs between tissue structural preservation, lipid detection sensitivity, and spatial integrity in MALDI-MSI. Because spatial integrity cannot be compromised for imaging lipids in carotid atherosclerotic plaques, Cryofilm combined with sublimation offers a clear advantage. This work strengthens MALDI-MSI workflows enabling more precise spatial mapping and deeper biological interpretation of atherosclerotic lipid distributions.

Publication date: Available online 11 January 2026 Source: Clinica Chimica Acta Author(s): Wu Yan, Ruifang Shi, Wen Zheng, Wentao Yang, Francis Manyori Bigambo, Wei Pan, Wenjing Zhang, Xu Wang

Insulin-like Growth Factor I (IGF-1) is crucial for growth, metabolism, and cell proliferation. Its detection is significant for diagnosing and monito…

As a common ingredient in sunscreens, oxybenzone has been established as a major factor in coral bleaching. Previous studies have revealed the toxic m…

Publication date: Available online 9 January 2026 Source: International Journal of Mass Spectrometry Author(s): Luciana Rivera Molina, Robert Brand, Calum Bochenek, Chrys Wesdemiotis

Micro(nano)plastics have received increased attention as environmental contaminants due to their harmful effects on ecosystems and human health. Conve…

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) libraries have limited capabilities for identification of …

Mass spectrometry-based lipidomics has emerged as a crucial field for unraveling the complexity of biological systems through comprehensive profiling of lipid species with unparalleled sensitivity and specificity. Among the available techniques, matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI imaging, or MALDI-IMS) stands out as a powerful spatial lipidomics tool, enabling the visualization of distribution and localization of individual lipid classes and species directly within biological tissues. The spatial context of lipids provided by MALDI imaging is especially valuable for studying nutritional and developmental processes in heterogenic tissues. The reliability and quality of MALDI imaging data critically depend on sample preparation, which must preserve both tissue morphology and analyte integrity. Here we introduce a sample preparation protocol for Drosophila melanogaster larval tissue, addressing key limitations of standard protocols such as thin-sectioning. Owing to the small size of Drosophila tissues and the flat morphology of organs such as the fat body, our approach enables direct imaging of the inner organs of the larvae without sectioning. This not only streamlines the workflow and minimizes tissue disruption but also allows simultaneous analysis of all major internal organs in a single measurement. Our approach not only facilitates high-quality MALDI-IMS data acquisition from complex larval tissues but also enables the localization of a broad spectrum of lipid species complementary to data gained by established techniques like liquid chromatography mass spectrometry (LC-MS). These advances position MALDI imaging, when coupled with our optimized preparation workflow, as an indispensable technique for spatially resolved lipidomics studies in small model organisms such as Drosophila larvae. Graphical Abstract