CRYOprotectants: Notes of an amateur

Twink (
Mon, 15 Dec 1997 22:34:16 -0500 (EST)

I submit for comment the following. I know some of this is probably
covered elsewhere, but I just wanted to get this out in case it isn't.

cp = cryoprotectant

Protein: Anders mentioned some proteins denature. I'm not
sure if this is because of low temperatures, interaction with cps or
some other process(es). If it is the second, one would expect a good
cp not to do this. (Or perhaps not: maybe some damage does not
matter than much. This needs to be evaluated.)
Other biomolecules: DNA, RNA, chlorestorol, lipids, can be
tested too to assess effects and damage of cps. Together with protein
tests, a damage marker shoudl be sought so as to reduce the number
of initial tests.
Nerve connections: Anders brought up a good point of sacrificing
axons for synapses or vice versa. However, it remains to be seen if any
cps do more damage to one or the other and whether there is a trade
off involved.
Nerve revival: Aside from examining damage to nerve
connections, reviving nerve cells and networks of such to operational
condition should be a test too. (The ultimate test being full revival
of a brain, but that would be far off into the future.)
Cellular damage: Other cells should be examined too. This
might result in finding a cell type marker. Perhaps some type of cell
is easier to work with in a lab setting and can be used in the stead of
nerve cells for initial tests.

Need for both quantitative and qualitative measures.
Ex. quantitative: percentage of protein in solution denatured.
Ex. qualitative: types of protein damage, such as crosslinking
versus breakdown.

Note tolerance level to cp.
Does it cause any damage?
More than one cp?
Is a cp "cocktail" better than one cp?
Perhaps different cps should be used for different
Perhaps different cps should be used at at different
times in the process?
Is the cp easy to store and maintain before use?
Is it easy to manufacture?
What is its long term optimal working temperature?

Related issue:
Design of "home" cryonics kit for use in emergency situations.
(This involves messy legal issues, but the design of
one might lead to a wider acceptance of cryonics by
making it a fait accompli.)


Daniel Ust

P.S.: Where can I subscribe to any cryonics lists?