What is cryopreservative solution?

Answer 1

When you freeze living tissue, you will likely end up harming it. Mainly because your cells are made up mainly of water and this expands when it turns to ice, bursting the cells and etc. Cryopreservatives can work in a few ways...and probably some I'm unaware of - it's a very active field.

Anyhow, commonly they work by mixing with the water and lowering its melting point. So instead of ice you just end up with a sort of thick syrup. This is then cooled extremely quickly so that the water vitrifies...which you can picture as freezing without forming ice.

As you probably know, ice has a very special structure and naturally it takes take for the water to arrange in such a way upon freezing, albeit only the smallest fraction of a second.

Anyhow, if you lower the temperature fast enough, the water doesn't have time to form this structure before it looses (most of) its kinetic energy and so instead you end up with a sort of glass. Frozen water but with none of undesirable expansion that occurs with ice.

This is useful for freezing tissue, as mentioned...but it's also great for freezing proteins for structural analysis. Commonly employed in Cryo EM techniques.

A problem with this can be that the cryopreservative damages the cell, as many are toxic. With protein analysis, the cryopreservative may ligand to the protein, giving an incorrect structural analysis. It's problematic but there you go.

I think dimethyl sulphoxide is classic textbook example of a cryopreservative. Keep in mind, my knowledge of all this is merely a side-note in my chemistry education and you may want to read up on this yourself, I claim no large expertise in this particular area.

Answer 2

A cryopreservative solution is a substance used to protect cells or tissues from damage during freezing and storage at low temperatures. It typically contains chemicals that help prevent ice crystal formation and other harmful effects that can occur during freezing and thawing processes. This solution is commonly used in cryopreservation techniques for preserving biological samples.