Luckily, hypochlorite treatment and fixation are by themselves sufficient to open eggs. This technique should work for virtually all polyclonal sera most monoclonals, as long as the major epitopes do not depend on disulfide bonds. Animals fixed in this way can be stained with X-gal. Wash them free of bacteria with water, leaving them in water in a microfuge tube on ice. Frozen samples may be processed immediately or stored indefinitely.
Methanol precipitates proteins, reducing diffusion before crosslinking.
Spermidine and formaldehyde together crosslink proteins. Freezing cracks egg shells, letting the fixatives in. Agitate gently but keep tubes upright because the cap may pop open from the O2 pressure. Do not over-wash, so disulfides do not reform. BO3 buffer provides the basic pH needed for the reaction.