&gt; Aldehydes covalently bond and crosslink the proteins and irreversibly kill all of the fixed cells.<p>That is the textbook answer, however these bonds are only &quot;irreversible&quot; as a matter of biochemistry. You can actually break any chemical bond by increasing the temperature enough. The problem for our purposes is that this means destroying the structure.<p>&gt; There is zero hope that this provides a solution to cryopreservation except in the slice it up and look at it under the microscope sense.<p>The trick to reversing the bond without damaging the structure would be in delivering high enough amounts of energy with high enough precision to have only the intended effects. This may or may not be physically possible. However, to rule out the possibility completely, we would need to consider a wide variety of physical interactions that are well outside the range of biology and wet-solvent chemistry, in addition to the full spectra of potential biomimetic and biological approaches.