Postembedding adjuvants in routine microtomy of paraffin-processed tissues.

Soaking the exposed face of routine paraffin-processed tissue blocks from human autopsies in solutions containing either 60% ethyl alcohol-glycerol 9:1; glycerol-aniline 9:1; 5% aqueous phenol; 5% aqueous Photo-flo, or 10% aqueous ammonium hydroxide for 2--4 hours at 0--4 C resulted in greater ease of ribboning and overall improvement of slide quality in the majority of sections compared to the results with the same blocks soaked only in water at 0--4 C. The use of postembedding adjuvants, especially 10% aqueous ammonium hydroxide, presents a simple, convenient, inexpensive means of increasing section quality with routine as well as refractory paraffin-embedded tissue without sacrificing tissue adhesion, staining qualities or cellular detail.