osmium tetroxide


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osmium tetroxide

n.
A volatile poisonous pale yellow solid, OsO4, with a pungent smell, used as an oxidizing agent and in solution to stain and fix biological material, especially lipids. Also called osmic acid.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

osmium tetroxide

n
(Elements & Compounds) a yellowish poisonous water-soluble crystalline substance with a penetrating odour, used as a reagent and catalyst in organic synthesis. Formula: OsO4
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
References in periodicals archive ?
Lung parenchyma with multiple fat emboli (hematoxylineosin with osmium tetroxide overstaining, original magnification X10).
Post fixation was made in 1 % osmium tetroxide buffered to PH 7.4 with 0.1 M phosphate buffer at 4 [degrees]C for 1-2 hours, washed again in phosphate buffer to remove excess fixative.
For preparing the cervical cell specimen based on the HMDS, first, the two fixation processes were implemented by rinsing the specimen with 5% glutaraldehyde in 0.1% PBS for 2 hours and osmium tetroxide for 1 hour as presented in Figure 2.
Oil droplets were occasionally observed in plastic sections of worms fixed for EM using osmium tetroxide.
For TEM analysis, the samples were processed as described for SEM procedures up to the fixation in osmium tetroxide 1% for two hours.
The method involved treating 90 [micro]m thick plywood sections, which had been cut transversely through the wood-coaling interface using a sliding microtome, with osmium tetroxide (Os[O.sub.4]) prior to examination with a field-emission scanning electron microscope (FE-SEM) operating in backscattered electron imaging (BEI) mode.
The later range from formalaldehyde, gluteraldehyde, to osmium tetroxide solutions, depending on type of tissue and purpose.
Aqueous solutions of "osmium tetroxide," or "osmic acid," are superior oxidizing agents for organic synthetic reactions.
The technique uses a 1% solution of osmium tetroxide (Os[O.sub.4]), a major fixative of choice for electron microscopy, to stain tissues differentially.
Each gill was fixed in 4% glutaraldehyde and postfixed in 1% osmium tetroxide. RNA and DNA content was measured in gills 4 and 7 from the contralateral side.
(Linyphiinae, Micronetini); Oedothorax gibbosus (Blackwall 1841) and Gongylidium rufipes (Linnaeus 1758) (Erigoninae); and Drapetisca socialis (Sundevall 1833) were dissected and fixed in 2.5% glutaraldehyde in 0.1 M phosphate buffer followed by postfixation in buffered 2% osmium tetroxide. After rinsing, the specimens were dehydrated in graded ethanols and embedded in Araldite or Spurr's resin (Spurr 1969).
They were postfixed in 1% osmium tetroxide in 0.1 M sodium cacodylate buffer at 4[degrees]C for 1 h.