Despite their small size, cells are full of water, and it can accumulate outside of them, too.
When it gets cold enough, the liquid freezes and forms a solid in or around the cell’s membrane. Ice breaking down, rupturing and transforming can cause unintentional damage to the cell’s composition. The process causes physical distress, hurting or killing biological materials. Using cryoprotectants and vitrification could be the key to maintaining these sensitive structures. What is cryopreservation, and how does vitrification prevent cell damage?
What Is Cryopreservation and Vitrification?
Cryopreservation is the process of taking biological materials and freezing them with such low temperatures that it stops all activity. Usually, experts do this with liquid nitrogen, which forces all cells, chemicals and physical responses to halt, as if frozen by time.
Interestingly, some plants have developed the ability to vitrify their biologies to withstand extreme temperatures. The process could be so intense that a creature could stop its heart to endure climates that would endanger most other species.
Vitrification is another process common in the medical industry, but some may be familiar with it because of how the food industry uses it to maintain colour and texture in seafood and fruits. It turns a liquid into a solid with rapid-cooling technology, producing a glasslike product. Experts may also expose a material to extreme heat so it can vitrify when introduced to cooler temperatures.
This is helpful for dangerous applications, like disposing of hazardous waste. Professionals can surround a substance in vitrification so it becomes encased in glass, preventing cross-contamination or leaching. This shows the diversity of vitrification’s applications, especially when ice crystal formation can lead to more unexpected damage.
In cryopreservation, vitrification is most commonly used to preserve embryos and egg cells — or oocytes — for fertility treatments. It also helps with cold chain management, keeping delicate substances cold, like vaccines, when travelling to their destinations. Some research indicates cryonics could allow brains to repair themselves or preserve entire human bodies in the future.
Why Is It Important to Prevent Ice Crystal Damage?
Ice crystal damage is essential in cells for various reasons, depending on the application and industry. For the most part, scientists need it to let cells heal or to safeguard them from other threats. Other industry stakeholders need to stop ice crystal formation because it threatens product quality.
Medical and Pharmaceuticals
Letting ice crystals form in biological tissues, organs and more could lead to cell death. Frozen liquids have sharp edges, puncturing membranes and exposing the cell’s inner workings to harmful influences, like salts. The physical pressure of ice is another critical factor. It weighs down the cell, potentially compressing it until it is so stressed that it breaks down.
Patients recovering from severe illness cannot afford these dangers. Pharmaceutical companies must also avoid this, as they attempt to preserve volatile medicines relying on biological reactions.
Food Production
Food needs to stop excess ice crystal formation for the same reasons as humans. Cell death leads to poor food quality and exposure to contaminants. Weaker cells compromise product integrity and can damage a company’s reputation. Companies need processes like vitrification to make foods less susceptible to environmental deterrents that cause them to rot, change colour or become less nutrient-dense.
Pottery
Ceramics experts use vitrification to ensure their products do not crack. If the material is too porous, then the pieces lose their structural integrity. When fired, the wet clay fuses together, and glass forms within its pores. This closes up the material, making it more resilient. This is most common in materials like porcelain, which do not use a glaze to create a water-resistant surface layer.
Biodiversity Conservation
Like humans, animals need to prevent ice crystal damage, as it leads to longer, healthier lives. Conservationists can use cryopreservation and vitrification to preserve some endangered species, letting their organs or tissues heal in this frozen state. It could also keep reproductive materials safe for breeding initiatives.
Energy
Power plants, especially in the nuclear sector, create tons of waste by-products. These are harmful to the environment, so most of it is stored in safehouses. If disposed of improperly, the radioactivity can have irreversible impacts on the planet and biodiversity. Vitrifying hazardous waste prevents toxic cells and residue from seeping into soils and waterways, as if housing it in a glass box in an immobilised state.
How Does Vitrification Prevent Cell Damage?
The benefits of cryopreservation and vitrification extend beyond cell health maintenance. There are other unexpected ways it keeps harm at bay.
Reduces Reliance on Slow-Freezing Methods
Historically, most assisted reproduction experts have used slow-freeze techniques to work with stored eggs and embryos. However, this method has varying degrees of success. It causes notable cryo-damage and has stilted advancements in fertility preservation. Now, vitrification promises higher chances of survival compared to older techniques.
Encourages Use of Cryoprotective Agents (CPAs)
Most vitrification strategies use CPAs like ethylene glycol and sucrose because they promote a stable glass transition and thawing process. They do so by lowering freezing points, making more severe temperatures unnecessary. Experts remove CPAs from the samples when they are finished to prevent negative side effects on the cell.
CPAs make the environment more suitable for rapid freezing, whereas their biological characteristics would not typically be suited or react poorly under those conditions.
Removing Crystal Creation
Other freezing practices, like slow freezing, create more ice crystals, which increases the risk of using them as a preservation method. Vitrification removes them from the equation entirely, giving experts a crystal-free alternative. While it creates a substance that appears like glass, it more closely resembles gel instead of crystals. Studies on this have successfully discouraged DNA fragmentation, improving oocyte health.
Trying Not to Break the Ice
Cryopreservation and vitrification prevent ice crystals from breaking and hurting cells. These processes allow experts to control the conditions around biological samples, food or ceramics, helping them have a longer lifespan. Researchers are finding new ways every year to make these methods more effective. Eventually, they could transform everything from medical treatment to food accessibility.