
The main problems associated with freeze-drying of biological material for electron microscopy concern the freeze-drying temperatures and times necessary to minimize artifacts. Due to the many parameters involved these problems have to be resolved experimentally. It can be shown that good morphological preservation of chemically unfixed material is possible when freeze-drying is done exclusively in a temperature range between -80 degrees C and -50 degrees C. OsO4 vapour fixation of the freeze-dried tissue is not necessary and should be avoided because it may cause ion redistribution artifacts. Embedding at low temperature of properly freeze-dried material does not seem to disturb structure and ion distribution of the freeze-dried material. Hence, sections of such freeze-dried material and embedded biological material seem to be suitable for microanalysis. Preliminary micro-analytical results obtained from sections of freeze-dried and Lowicryl K11M embedded muscle reveal an uneven distribution of potassium in the sarcomeres similar to the visualized uneven distribution of the electron dense thallium (potassium surrogate) in frozen hydrated cryosections. A comparison of different cryomethods shows that freeze-drying and embedding is the simplest way to obtain stable thin sections of chemically unfixed biological material which, for instance, may be used for future microanalytical investigation of the interaction of proteins with physiological and non-physiological ions.
Ranidae, potassium, Muscles, Histological Techniques, ion redistribution, Life Sciences, freeze-substitution, Osmium, microanalysis, Microscopy, Electron, Freeze Drying, cesium staining, Freeze-drying, striated muscle, Animals, Humans, cryosectioning, Indicators and Reagents, Lymphocytes, low temperature embedding
Ranidae, potassium, Muscles, Histological Techniques, ion redistribution, Life Sciences, freeze-substitution, Osmium, microanalysis, Microscopy, Electron, Freeze Drying, cesium staining, Freeze-drying, striated muscle, Animals, Humans, cryosectioning, Indicators and Reagents, Lymphocytes, low temperature embedding
| selected citations These citations are derived from selected sources. This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | 10 | |
| popularity This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network. | Average | |
| influence This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | Top 10% | |
| impulse This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network. | Average |
