Biomaterial Database

Observations on the kinetics of uranyl acetate and phosphotungstic acid staining of chromatin in thin sections for electron microscopy. 1984

P A Cattini, and H G Davies

When thin sections of spermatogenic chromatin are fixed with either glutaraldehyde alone or postfixed with osmium tetroxide (OsO4) and stained with uranyl acetate (UAc) for increasing times, even after as little as 1 min, stain uptake is proportional to section thickness. Greater UAc uptake is observed in chromatin fixed with glutaraldehyde only, but seen with postfixed chromatin. Lead citrate poststaining of chromatin fixed with either glutaraldehyde or postfixed with OsO4 increases UAc uptake by a factor of about 3. The staining of thin sections of spermatogenic chromatin with ethanolic phosphotungstic acid (PTA) shows a region where stain uptake is proportional to section thickness followed by a plateau. This staining pattern is seen in chromatin fixed with glutaraldehyde alone or postfixed with OsO4; similar levels for final PTA uptake are also observed. An increase in the resin content of embedded chromatin postfixed with OsO4 is proposed to explain the decrease and increase in the rate of migration of UAc and ethanolic PTA staining solutions, respectively.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008297	Male		Males
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D009942	Organometallic Compounds	A class of compounds of the type R-M, where a C atom is joined directly to any other element except H, C, N, O, F, Cl, Br, I, or At. (Grant & Hackh's Chemical Dictionary, 5th ed)	Metallo-Organic Compound,Metallo-Organic Compounds,Metalloorganic Compound,Organometallic Compound,Metalloorganic Compounds,Compound, Metallo-Organic,Compound, Metalloorganic,Compound, Organometallic,Compounds, Metallo-Organic,Compounds, Metalloorganic,Compounds, Organometallic,Metallo Organic Compound,Metallo Organic Compounds
D010772	Phosphotungstic Acid	Tungsten hydroxide oxide phosphate. A white or slightly yellowish-green, slightly efflorescent crystal or crystalline powder. It is used as a reagent for alkaloids and many other nitrogen bases, for phenols, albumin, peptone, amino acids, uric acid, urea, blood, and carbohydrates. (From Merck Index, 11th ed)	Acid, Phosphotungstic
D002645	Chickens	Common name for the species Gallus gallus, the domestic fowl, in the family Phasianidae, order GALLIFORMES. It is descended from the red jungle fowl of SOUTHEAST ASIA.	Gallus gallus,Gallus domesticus,Gallus gallus domesticus,Chicken
D002843	Chromatin	The material of CHROMOSOMES. It is a complex of DNA; HISTONES; and nonhistone proteins (CHROMOSOMAL PROTEINS, NON-HISTONE) found within the nucleus of a cell.	Chromatins
D004912	Erythrocytes	Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.	Blood Cells, Red,Blood Corpuscles, Red,Red Blood Cells,Red Blood Corpuscles,Blood Cell, Red,Blood Corpuscle, Red,Erythrocyte,Red Blood Cell,Red Blood Corpuscle
D005976	Glutaral	One of the protein CROSS-LINKING REAGENTS that is used as a disinfectant for sterilization of heat-sensitive equipment and as a laboratory reagent, especially as a fixative.	Glutaraldehyde,Cidex,Diswart,Gludesin,Glutardialdehyde,Glutarol,Korsolex,Novaruca,Sekumatic,Sonacide,Sporicidin
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia