Formaldehyde fixation chemistry

In 1991 Shi et al. published their seminal observation that high-temperature incubation of formalin-fixed, paraffin-embedded (FFPE) tissue sections in buffers for short periods led to improved immunohistochemical staining.1 However, more than 15 years later, heat-induced antigen retrieval (AR) remains largely an empirical procedure, requiring the optimization of several critical parameters by trial and error.2,3 Further improvements in AR will require an in-depth understanding of the chemistry of formaldehyde fixation and the molecular mechanism(s) underlying the AR method. 

Puchtler H, Meloan SN. On the chemistry of formaldehyde fixation and its effects on immunohistochemical reactions. Histochemistry 1985 82 201-204. 

These functional characteristics reflect what is known about the chemistry of formaldehyde fixation, much of which has previously been reviewed by Fox and by Shi et al.1,2 Some significant facts about formaldehyde fixation of proteins include ... 

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