Permanganate—A New Fixative for Electron Microscopy

Permanganate—A New Fixative for Electron Microscopy

During the early phases of tissue sectioning for electron microscopy, virtually all of the standard cytological fixatives were tried. Of these, osmium tetroxide appeared to give the best preservation, and this was further improved by buffering the fixative solution at a slightly alkaline pH (Palade (1)). A variant developed by Dalton (2) contains Os04 in a chromate-dichromate system. Formalin h...

Electron Microscopy of the Sperm Tail Results Obtained with a New Fixative

The details of a new fixation procedure using 40 per cent osmium tetroxide in carbon tetrachloride are presented. This fixative is a good general preservative, gives a higher contrast than the ordinary osmium fixatives, and may also preserve structures that are not otherwise readily revealed. Some possible reasons for the increased contrast are discussed. Micrographs of the sea urchin spermatoz...

A New Epoxy Embedment for Electron Microscopy

A new epoxy embedding mixture has been developed utilizing Maraglas 655 and Cardolite NC-513 with benzyldimethylamine (BDMA) as a curing agent. This epoxy mixture permits cellular preservation comparable to that obtained with Epon 812, ease of preparation of tissues, a wide range of miscibility, low viscosity, and, most important, ease of sectioning on a Porter-Blum microtome. In contrast to Ep...

Electron Microscopy of Fowl Pox Virus

Preservation of ruminal bacterium capsules by using lysine in the electron microscopy fixative.

Ruminal bacteria from axenic cultures of Ruminococcus flavefaciens FD1, Butyrivibrio fibrisolvens 49, and bacterial types from the ruminal ecosystem that were fixed with 50 mM lysine (l-lysine hydrochloride) added to glutaraldehyde had better-preserved capsules and extracellular material than bacteria fixed without lysine.