Cryo-optical microscopy freeze-frames mobile exercise

27 Aug 2025

University of Osaka approach visualizes cell dynamics throughout transient processes.

Fluorescence microscopy reveals mobile morphology and dynamics in outstanding element, however reaching clear visualization at quick acquisition charges stays a problem.

A elementary trade-off between temporal decision and the way a lot gentle will be collected for a picture restricts the spatial element with which quick dynamic mobile occasions will be captured, which means vital options are misplaced in dim noisy photographs.

A venture on the University of Osakaa has now developed a cryo-optical microscopy approach designed to take a high-resolution, quantitatively correct snapshot at a exactly chosen timepoint in dynamic mobile exercise.

Published in Light: Science & Applications, the findings might present detailed insights into pattern dynamics with improved spatial decision and temporal accuracy in observations.

“Instead of chasing speed in imaging, we decided to freeze the entire scene,” commented Kosuke Tsuji from the University of Osaka.

“We developed a special sample-freezing chamber to combine the advantages of live-cell and cryo-fixation microscopy. By rapidly freezing live cells under the optical microscope, we could observe a frozen snapshot of the cellular dynamics at high resolutions.”

Although the potential advantages of cryofixation over chemical fixation in a fluorescence microscopy operation are understood, the optical properties of some fluorescent probes can differ beneath cryogenic situations in comparison with room temperature or could present temperature dependencies, complicating the imaging operation.

The venture’s optical platform employed 4 microscopy modalities: a widefield fluorescence microscope; a structured illumination microscopy (SIM) system; a hyper-spectral slit-scanning fluorescence microscope; and a multimodal system combining SIM with slit-scanning Raman microscopy.

Intricate mobile data from a number of views

By combining UV gentle stimulation to induce calcium ion waves with an electrically triggered cryogen injection system, the system might freeze the calcium ion waves at a particular time level after the initiation of an occasion with 10 ms precision. This let the crew arrest transient organic processes with unprecedented temporal accuracy.

The venture additionally studied the way to mix its completely different imaging strategies, which will be troublesome to align in time. A near-instantaneous freezing of samples implies that a number of imaging modalities will be utilized sequentially with out worrying about temporal mismatch.

In its examine, the venture mixed spontaneous Raman microscopy and super-resolution fluorescence microscopy on the identical cryofixed cells, giving it a view of intricate mobile data from quite a lot of views at the very same cut-off date.

Trials on samples together with HeLa most cancers cells confirmed that the morphological, calcium ion and chemical dynamics of the
cells have been fastened and imaged efficiently by this cryo-optical methodology. Data associated to in any other case intangible data reminiscent of pH and redox state may be detected, utilizing practical fluorescent probes and retrieved from the cryo-fixed cells.

“This research began with a bold shift in perspective: to arrest dynamic cellular processes during optical imaging rather than struggle to track them in motion,” mentioned Osaka’s Katsumasa Fujita. “We believe this will serve as a powerful foundational technique, offering new insights across life-science and medical research.”