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glycerol as a protectant during freezing? - workingprinciple (Jun/19/2008 )

Hallo all,

can anybody explain me in short how glyerol procets cells during freezing?

If I am not mistaken glycerol penetrates the cells, but how does it really protect the organisms?
It alters the saltconcetration ? or it prevents the fluid in the cell from freezing itself?

-pito-

Hi Pito,

glycerol minimizes (or in higher concentrations even prevents) the production of water crystals, that can be sharped edged and would pierce into the cell walls.

-Chakchel-

QUOTE (Chakchel @ Jun 19 2008, 10:35 AM)
Hi Pito,

glycerol minimizes (or in higher concentrations even prevents) the production of water crystals, that can be sharped edged and would pierce into the cell walls.


prevents in higher concentration, you mean that the glycerol lowers the freezing temperature so much that there is no freezing at all?

-pito-

QUOTE (pito @ Jun 19 2008, 12:38 PM)
QUOTE (Chakchel @ Jun 19 2008, 10:35 AM)
Hi Pito,

glycerol minimizes (or in higher concentrations even prevents) the production of water crystals, that can be sharped edged and would pierce into the cell walls.


prevents in higher concentration, you mean that the glycerol lowers the freezing temperature so much that there is no freezing at all?


depends on the temperature here

-gebirgsziege-

QUOTE (gebirgsziege @ Jun 19 2008, 02:52 AM)
depends on the temperature here

That is a cool table! Thanks.

-cellcounter-

To the explanation of freezing damage being based on ice crystals that "puncture" the cell membrane.

Anyone actually have citation for data - better yet micrographs - demonstrating this?

-jorge1907-

QUOTE (jorge1907 @ Jun 20 2008, 10:47 AM)
To the explanation of freezing damage being based on ice crystals that "puncture" the cell membrane.

Anyone actually have citation for data - better yet micrographs - demonstrating this?



I was thinking the same thing.
I did read some text that stated that glycerol helped in preventing the formation of larger cristals. (glycerol stimulates the formation of smaller cristals)
But I indeed did not read that it would helpt in preventing the puncturing of cell membrane or cellparts in general.

However I do think its a logical idea that larger cristals might damage the cell structure.
So I think it might be true.

-pito-

If science were always logical - we'd not bother running the experiments.

-jorge1907-