Fixation and Embedding

Electron energy loss spectroscopy 1-10 mg 0.1 pm Boron must stay during fixation and embedding or sample must be cryoprepared 30 ppm yes yes medium-poor... 

Proteins can be detected in tissue sections or cell cultures using similar immune detection systems. Use of an antibody to detect specific proteins in tissues is called immunohistochemistry, whereas detection of proteins in cell suspensions is called immunocyto-chemistry. Tissues can be prepared by fixation and embedding in paraffin wax, or by rapid freezing in a compound that inhibits ice formation in the tissue, so as to preserve cell morphology. Some antibodies do not work well with paraffin-embedded tissues, probably because the antibody cannot access the antigen properly (133). The most common labeling system used for detection of the bound antibody is an enzyme-coupled secondary antibody that produces a color reaction... 

The IEM double-labeling method described was performed with cells fixed in 2% paraformaldehyde and 0 04% glutaraldehyde, and embedded in Lowicryl K4M, LR White, or LR Gold. Other fixation and embedding procedures should work equally well, provided that the specimen resists the chemicals used m the silver enhancement. 

Curiously there have been few examples in the literature (outside of work with cereals) which use light microscopy of embedded sections as anything other than an adjunct to TEM or SEM [27,28]. Thus, fixation and embedding schedules relate to the electron microscopies ... 

Where a cell surface antigen is of interest, and particularly where the cells are grown in vitro, a labelling method which avoids all the problems of fixation and embedding can be used. Antibody and conjugate incubations can all be completed prior to fixation and embedding for TEM or critical point drying for SEM. 

---