No dyes, less cell stress: How mid-infrared ultrasound imaging tracks lipids live

A team at Helmholtz Munich and the Technical University of Munich (TUM) has developed a new microscopy technique that can distinguish lipid species in living cells—in particular cholesterol and sphingomyelin—and map them without the need for chemical labeling. By combining mid-infrared illumination with optoacoustic detection, the method reads the lipids' natural spectral fingerprints, eliminating the need for specific fluorescent tags, which are laborious to develop and may interfere with lipid function. The team published its results in the journal Nature Methods.