Microfluidics-Based Workflow Developed for High-Resolution Lipid Imaging in C. elegans

Studying how fat molecules function across tissues has been constrained by the difficulty of imaging lipids in very small organisms. Caenorhabditis elegans presents both an opportunity and a challenge in this field: while its anatomy and genetic similarity to humans make it valuable for research, its small size has limited precise lipid mapping. Now, a new workflow from Okayama University researchers overcomes this challenge by integrating microfluidics, cryo-sectioning, and mass spectrometry imaging. Their method, described in Scientific Reports, provides three-dimensional lipid maps at unprecedented spatial resolution while preserving internal structure.

The workflow begins with immobilizing young adult worms on a custom-designed microfluidic chip. Animals are then embedded in a gelatin–carboxymethyl cellulose matrix, sectioned with a cryotome, and prepared for matrix-assisted laser desorption/ionization mass-spectrometry imaging (MALDI-MSI). To validate the results, each section undergoes Oil Red O staining, which highlights neutral fats, ensuring consistency between conventional and novel approaches. “This is the first time we’ve been able to map lipid distributions in C. elegans with such spatial resolution while preserving internal structures,” explained Sara Mandic, first author of the study.

A key advantage of the method is its ability to overcome trade-offs common to traditional techniques. Previous approaches often stained lipids without identifying them, or identified them without maintaining spatial detail. The new workflow achieves both, revealing the chemical identity of lipids alongside their anatomical location. Mandic explains, “Our technique gives researchers a reliable way to study fat dynamics in specific tissues of a single nematode.”

The workflow also enables three-dimensional reconstruction. By stacking serial sections, researchers generated volumetric views of lipid organization throughout the worm’s ~1 mm body. These reconstructions captured patterns across tissues such as the pharynx, intestine, and reproductive system with remarkable anatomical fidelity. Importantly, reproducibility tests showed that biological variation exceeded technical error, demonstrating precision and robustness. “This method allows us to see not just what lipids are present, but exactly where they are inside the body—whether in the intestine, pharynx, or embryos,” adds Mandic.

Looking ahead, the team aims to apply this workflow to worms carrying mutations linked to disease and to integrate it with quantitative lipid analysis. As Mandic concludes, “Our work opens the door to visualizing lipid biology in an entirely new way—one that’s precise, reproducible, and rich in detail.”