Liquid Nitrogen Flash Freezing
Liquid Nitrogen Flash Freezing - Related Videos
28:32
Flash Freezing and Cryosectioning E12.5 Mouse Brain
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Cited by 6 •
2007
Demonstrated in this video are the techniques for flash freezing and sectioning embryonic brain tissue from mouse. Useful tips for using the cryostat are given, including troubleshooting methods that can be used while cutting to ensure that the resultant tissues sections are free of cracks and other distortions.
06:42
A Multi-hole Cryovial Eliminates Freezing Artifacts when Muscle Tissues are Directly Immersed in Liquid Nitrogen
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Cited by 9 •
2017
This protocol describes a procedure to freeze muscle tissues by plunging them directly into liquid nitrogen. This protocol also highlights a new cryovial that can avoid the "blanket effect" of nitrogen gas when liquid nitrogen contacts the tissue surface of a specimen.
10:01
Flash-and-Freeze: A Novel Technique to Capture Membrane Dynamics with Electron Microscopy
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Cited by 7 •
2017
We developed a novel technique in electron microscopy, "flash-and-freeze," that enables the visualization of membrane dynamics with ms temporal resolution. This technique combines the optogenetic stimulation of neurons with high-pressure freezing. Here, we demonstrate the procedures and describe the protocols in detail.
02:42
Preparation of Cancer Spheroid Blocks by Flash Freezing: A Procedure To Preserve Cancer Spheroids in Frozen Matrix Blocks
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2023
This video demonstrates the preparation of cancer spheroid blocks by flash freezing, a technique in which a tissue sample of interest is frozen to an ultracold temperature, restraining the spheroids inside the matrix.
08:18
Degassing Liquids with Freeze-Pump-Thaw Cycling
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2023
Source: Laboratory of Dr. Neil Branda — Simon Fraser University Degassing refers to the process by which dissolved gases are removed from a liquid. The presence of dissolved gases such as oxygen or carbon dioxide can impede chemical reactions that utilize sensitive reagents, interfere with spectroscopic measurements, or can induce unwanted bubble formation. A number of different techniques are available for degassing liquids; some of these include heating, ultrasonic agitation, chemical...
FAQs
Direct contact with liquid nitrogen rapidly removes heat, shortening the time available for ice crystals to grow. Limiting large crystals helps maintain cell boundaries, membranes, and tissue architecture rather than allowing them to be disrupted during slower cooling. For neuroscience samples, that structural preservation supports later examination of neuronal morphology and other spatial features.
Rapid cooling helps preserve molecular composition while sample processing is paused. This matters because protein localization and gene expression can change if brain tissue, neural cultures, or biochemical samples remain unprocessed. Flash freezing therefore supports assays that aim to measure molecular features as they existed near collection, rather than changes introduced by delay.
The key difference is cooling rate. Direct contact with liquid nitrogen removes heat quickly, limiting the growth of large ice crystals; slower cooling allows more time for crystal formation and possible disruption. This distinction influences whether samples retain the organization needed for microscopy and immunohistochemistry, as well as molecular analysis.
The workflow begins by identifying the sample and intended downstream analysis. Researchers then expose the biological material to liquid nitrogen for rapid cooling. After freezing, the sample can proceed to cryosectioning, microscopy, immunohistochemistry, or molecular assays. This sequence links preservation to the feature being measured, whether tissue architecture, neuronal form, protein localization, or gene expression.
Brain tissue is useful when researchers need to preserve tissue architecture and neuronal morphology. Neural cultures provide cellular material for examining neural structure and molecular features. Biochemical samples are suited to analyses focused on molecular composition. In each case, flash freezing helps maintain the sample until later microscopy, immunohistochemistry, or molecular testing.
Preserved structure supports assessment of neuronal morphology, while retained molecular composition supports evaluation of protein localization and gene expression. These readouts answer different neuroscience questions: microscopy and immunohistochemistry can reveal spatial organization, whereas molecular assays examine biochemical or gene-expression features. Using rapid freezing before analysis helps reduce changes caused by delayed processing.