Ammonium Sulfide State Of Matter

Synthesis: Carbon With Three or Four Attached Heteroatoms

E. Kleinpeter , in Comprehensive Organic Functional Group Transformations Two, 2005

half dozen.17.2.5.1 Salts of monoesters of trithiocarbonic acid

The cherry-red trithiocarbonate anion S double bond CS₂ ²⁻ has been prepared by treating ammonium sulfide, strong aqueous ammonia, alkali metal sulfides, or aqueous alkaline metal hydroxide with CS ₂ <1983HOU(E4)408, COFGT-2>. To promote the reaction, a phase-transfer catalyst or an anion-commutation resin has oft been used <1998JCR(Due south)454>.

The reaction of aliphatic and aromatic thiolates with polarized CS_two leads to the formation of the salts of the monoesters of trithiocarbonic acids, e.g., the stable triethylbenzylammonium (TEBA) salts of the corresponding trithiocarbonic acid <1996JCR(South)64> (Equation (40)).

(40)

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Laboratory Methods Used in the Investigation of the Haemolytic Anaemias

Lynn D. Robertson , David Roper , in Dacie and Lewis Practical Haematology (Twelfth Edition), 2017

Schumm test

Method

Cover the plasma (or serum) with a layer of ether. Add a one-10th volume of saturated yellow ammonium sulphide and mix information technology with the plasma. Then view it with a manus spectroscope. If methaemalbumin is present, a relatively intense narrow absorption band at 558 nm will be seen in the dark-green.

Significance of methaemalbuminaemia

Methaemalbumin is found in the plasma when haptoglobin is absent in haemolytic anaemias in which lysis is predominantly intravascular. It is a haem–albumin compound formed subsequent to the degradation of haemoglobin liberated into plasma. It remains in the circulation for several days or until the haem is transferred from albumin to the more highly avid haemopexin.

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Enzymes

Arun Kumar Sharma DSc, FNA, FASc , Archana Sharma DPhil, DSc, FNA, FASc , in Chromosome Techniques (Tertiary Edition), 1980

Mathers and Norman's method (1956)

This method has been practical for the written report of acrid phosphatase activity in malignant and benign tumours of the prostate glands.

Reagents

Incubation mixture containing G/10 aqueous sodium glycerophosphate solution, buffered to pH 4.9 with acetate buffer containing 0.12 per cent atomic number 82 nitrate solution.

3% aq. acerb acrid solution

2% aq. ammonium sulphide solution

i% aq. light green solution

Process

(1): Prepare 10 μm thick frozen sections and bring to water.
(2): Incubate in the incubation mixture at 37 °C for 5–15 min.
(3): Wash in 3 per cent acetic acid solution.
(four): Treat with fresh ammonium sulphide solution for 2 min.
(5): Rinse thoroughly in water.
(6): Stain with light light-green solution.
(seven): Rinse again in distilled water.
(8): Mount in glycerin jelly or dehydrate and mount in neutral balsam.

observations

Dark brown or black precipitate is formed at the sites of acid phosphatase activeness.

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Utilize OF ULTRASTRUCTURAL HISTOCHEMISTRY

Barbara A. Nichols , in Methods for Studying Mononuclear Phagocytes, 1981

B The Protocol for Aryl Sulfatase (see Appendix for formulas of solutions)

(1): Fix tissues for 10 min in 1.v% glutaraldehyde.
(2): Wash 3 times in sodium cacodylate wash buffer.
(3): Incubate specimens in aryl sulfatase medium at 30° – 37°C for thirty–90 min in a Dubnoff shaking incubator.
(4): Wash until clear with Michaelis launder buffer (v – 7 rinses).
(5): Catechumen reaction product with two% ammonium sulfide in Michaelis buffer for 5 – xv min. [In this step, the lead sulfate formed as a result of the reaction is converted to pb sulfide ( 35). The resulting specimen is easier to section than specimens prepared without this step.]
(6): Launder until clear with Michaelis buffer (8 – 10 washes).
(7): Pellet loose cells in a Beckman Microfuge.
(viii): Postfix in Palade'southward osmium at four°C for one hr.
(ix): Stain in cake for ten – 60 min with Kellenberger'due south uranyl acetate stain at room temperature.
(10): Dehydrate in ethanol and propylene oxide (run across Section 3.A), equally for acrid phosphatase.
(11): Embed in Epon.
(12): Cure at 60°C for 24 hr.

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Histochemical Detection of Enzymes

Franz Duspiva , in Methods of Enzymatic Analysis, 1965

a) Method involving precipitation of metallic salts

For about two decades only a few methods for the detection of oxidases in blood smears and histological sections were known; their value was much disputed. Now about xxx different enzymes can be detected histochemically. The first enzyme to exist detected by histochemical means was alkali metal phosphatase which was demonstrated simultaneously by Gomori ⁱ⁾ and Takamatsu ²⁾ . The orthophosphate liberated from glycerophosphate past the phosphatase was precipitated as the calcium salt (hydroxylapatite). In the original method the precipitate was transformed to silver phosphate (according to ^three) ) which became black on exposure to light and was therefore made visible. In 1941 Gomori ⁴⁾ introduced the method of converting the calcium phosphate to cobalt phosphate, which tin be transformed to the black sulphide by means of ammonium sulphide (cobalt sulphide method). Ane of the modifications published past Gomori ⁵⁾ is still used a great bargain.

The calcium-cobalt method is unsuitable for enzymes which have their pH optimum in the acid range, since calcium phosphate is soluble below pH 8. Calcium is therefore replaced by lead, which can exist used in the weakly acrid range upwards to pH six and tin can be converted to the black sulphide direct with H_iiSouthward.

Apart from the lead phosphate method there is as well one employing iron-hydroxyquinoline (germination of Berlin blue).

The cobalt sulphide method is used to detect all enzymes having esters every bit substrates which on hydrolysis produce an anion that can be precipitated with Ca²⁺. Glucose-six-phosphatase, fructose-1,half dozen-diphosphatase, ATPase, esterases and lipases can exist detected by this method.

According to ⁶⁾ the cobalt sulphide method does not give quantitative results, since the exchange of Ca for Co phosphate is not consummate. On the other hand, the substitution with silver is quantitative ⁷⁾ . All the same, the silver precipitate is oftentimes fibroid-grained and gives a less detailed movie. Losses of Ca and Co phosphate occur on rinsing the preparations. For recent suggestions to avert this mistake see the individual methods.

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Nitrosation involving metal-nitrosyl complexes

D.L.H. WILLIAMS , in Nitrosation Reactions and the Chemistry of Nitric Oxide, 2004

nine.3 Atomic number 26-sulfur cluster nitrosyls

In 1858 the French chemist Roussin prepared salts of the two ions Fe_fourSouthward_three(NO)₇ ⁻ and Fe₂Due south₂(NO)_four ⁱⁱ⁻, universally known every bit Roussin's blackness and red salt respectively [516] . Their synthesis is amazingly simple experimentally, but mechanistically must be very complex. The black common salt precipitates as the ammonium salt simply by mixing sodium nitrite, with iron(II) sulfate and ammonium sulfide. Their structures are shown in 32 and 33, and their general chemical science has been reviewed [517]. There has been a renewed interest in one aspect of their chemical science since the discovery of the amazing biological properties of nitric oxide, since the salts can readily release nitric oxide upon oxidation. This attribute volition be covered afterwards in Affiliate 12. This section volition deal with the possibility of these species acting also as electrophilic nitrosating species. Structural assay has revealed that the FeNO grouping is linear, although the N-O vibrational frequency is less than 1850 cm⁻¹. However in that location

is NMR prove [518] in favour of the linear arrangement. There are also references in the literature to reactions with secondary amines such as morpholine where nitrosamines are generated [519]. It is claimed that these reactions are faster than the conventional nitrous acid nitrosation. Germination of carcinogenic nitrosamines in this way may well account for the high incidence of oesophageal cancer is the Linxian valley in Northern China. Hither an particular in the local diet is a pickled vegetable, prepared using the local water supply, which is high in nitrate and nitrite levels. Analysis of this fabric has shown that it contains high levels of the cherry ester [Fe_ii(SMe)_ii(NO)₄] derived from Roussins' red table salt. A total chemical study has non been carried out but it is equally possible that nitrosamines could arise from loss of nitric oxide from the red ester, oxidation, generation of N₂O_iii leading to nitrosamine formation or as a direct nitrosation process from the cherry ester in the electrophilic NO⁺ transfer sense. The co-assistants of the carmine ester and proline to rats results in the formation of nitrosoproline. Equally a result of these studies the eating habits have been changed in the Linxian Province, resulting in the reduction of the incidence of cancer in the area.

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Embryology and Teratology

Ballad Erb , in The Laboratory Rat (Second Edition), 2006

5. Dam Necropsy and Collection of Fetal and Placental Data

In embryo-fetal development studies, dams are typically euthanized on gestation mean solar day 20 or 21 past carbon dioxide inhalation and are given a detailed macroscopic necropsy to observe lesions in the maternal organs. The uterus and ovaries are excised (Taylor, 1986; Barrow, 2000; Christian, 2001 ). The number of corpora lutea in each ovary is counted and recorded. The uterus of female person rodents that do non appear to be pregnant tin can be examined either by pressing the uterus between glass plates and examining it for the presence of implantation sites or past staining it with ammonium sulfide ( Kopf et al., 1964; Salewski, 1964). The weight of the gravid uterus may be recorded (required for chemic testing), and this value tin can exist used to calculate the corrected body weight (concluding body weight minus the gravid uterine weight), which tin be useful for evaluation of maternal body weight independent of uterine effects. The uterine horns are cutting open, and the chorionic and amniotic sacs are opened to expose the fetuses. The number and location of each implantation site are recorded. The status of each implant site (alive and expressionless fetus, early on or belatedly resorption) is recorded. The number of implantations is compared to the number of corpora lutea to decide preimplantation loss. An early resorption is a conceptus in which only placental remnants (metrial gland) are visible, and a belatedly resorption has both placental and fetal remnants visible. A live fetus is pink in color and will answer to stimulation. A dead fetus is often pale to tan in color and is not responsive to stimulation but does not demonstrate marked autolysis. Fetuses with marked autolysis are considered to be late resorptions (Taylor, 1986; Barrow, 2000; Christian, 2001). Individually identified fetuses are separated from the placenta past cutting the umbilical string, and any membranes are removed. The fetuses are then blotted dry and individually weighed. The individually identified placentas from alive fetuses are and then removed from the uterus, and after any remaining membranes are removed, they are individually examined for abnormalities in appearance and weighed. Placental weights normally correlate with fetal weights. Abnormal placentas can exist evaluated microscopically. According to the ICH guidelines (1994), information technology must be possible to relate all findings in a unmarried fetus; therefore, accurate fetal identification is very important.

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Investigation of Enzymes in Biological Preparations

Trevor Palmer BA, PhD, CBiol, FIBiol, FIBMS, FHEA , Philip L. Bonner BSc, PhD , in Enzymes (2nd Edition), 2011

15.three.1 Enzyme histochemistry

The sub-cellular location of many enzymes may be revealed by microscopy, provided suitable fixation and staining procedures are followed.

Tissues are frozen to below −twenty°C and sliced using a cryostat (a refrigerated microtome). This process ensures that the tissue is rigid, essential for obtaining thin slices (about 10μm thick) of satisfactory quality, and too minimizes loss of enzyme activity. The slices are then usually fixed in formaldehyde (formalin), HCHO, to prevent whatsoever subsequent diffusion of proteins taking place. Formaldehyde brings nearly cross-linking between side chain amino groups of proteins:

(xv.five) ${Protein-NH}_{ii} undefined + HCHO + H_{2} Due north-Poly peptide \to {Poly peptide-NH-CH}_{ii} -NH-Protein$

Nigh enzymes retain at to the lowest degree some activity later treatment. Nevertheless, some do non, and these take to be investigated without prior fixation. In either case, the tissue section is treated with a buffered solution of a staining mixture containing the substrate of the enzyme under investigation. The staining process requires the conversion of this substrate to the appropriate product, and and so tin can only take place in the regions where the enzyme is present. If possible, the product is immobilized after formation to prevent it diffusing abroad from the location of the enzyme.

For example, the substrate solution for the widely used pb-salt method for acid phosphatases includes sodium β-glycerophosphate and atomic number 82 ions in buffer at pH v.five. Any acrid phosphatase present in the tissue hydrolyses the β-glycerophosphate to produce glycerate, and the phosphate liberated in the process reacts immediately with the lead ions to grade insoluble lead phosphate (PbPO₄). This may be converted to a more than conspicuous production, also insoluble, by developing with a solution of ammonium sulphide:

(xv.vi) ${PbPO}_{4} undefined \overset{ammonium sulphide}{\to} PbS .$

In this way, a black precipitate of lead sulphide may exist visualized wherever acid phosphatase is located.

Many stains which testify upwardly conspicuously on optical microscopy are not suitable for use in electron microscopy, since their elective atoms are no more opaque to an electron beam than are the atoms normally present in the tissue. Merely atoms of large diminutive weight, e.g. those of heavy metals, scatter an electron beam sufficiently to cause their locality to be significantly more opaque than the rest of the tissue. Thus the lead-common salt method, discussed above, is 1 which can be applied to tissues being visualized past electron microscopy, since electron-opaque atomic number 82 phosphate is precipitated in the regions where acid phosphatase is present. (Notation that for electron microscopy, unlike optical microscopy, there is no reward in developing to catechumen lead phosphate to atomic number 82 sulphide, since both are equally electron-opaque.) Notwithstanding, ultra-thin sections (about eighty nm thick) are required for electron microscopy, so the sections prepared and stained every bit above must exist dehydrated (replacing water with alcohol) and embedded in epoxy resin earlier being farther sectioned on an ultramicrotome. Such investigations accept revealed, for instance, that acrid phosphatase is characteristically associated with lysosomes.

Antibodies raised against an enzyme from one species can ofttimes show cross reactivity with the same enzyme from a different species. Immunohistochemistry utilises the specificity of antibodies to determine the cellular location of enzymes in fixed tissue slices or cultured whole cells. The initial primary antibody-antigen interaction (normally with a monoclonal antibiotic to reduce non-specific interactions) tin can be visualised indirectly by an boosted incubation with a horseradish peroxidase- or alkaline phosphatase-labelled secondary antibiotic (normally a polyclonal antibody to enhance the detection) raised against the immunoglobulin species of the main antibiotic. The improver of substrates for the enzyme conjugated to the secondary antibody will consequence in the deposition of coloured material at the site of the antibiotic-antigen interaction (Fig. xv.2a). Alternatively, the detection can be visualized directly with a fluorescence microscope or confocal microscope, if the primary antibody is labelled with a fluorophore, east.g. fluorescein isothiocyanate (FITC). Dual labelling of two different enzymes on the same tissue can be achieved using ii antibodies with different fluorophores fastened, e.g. FITC (excitation 490 nm and emission 525 nm) and Texas Red (excitation 596 nm and emission 625 nm) (see Fig 15.2b).

A simple method of locating the distribution of enzymes in tissue sections of animals or plants is tissue printing. The tissue to exist analysed is cut with a abrupt bract and lightly pressed onto a nitrocellulose membrane, which retains an banner of the proteins in the tissue. The distribution of some enzymes, east.1000. peroxidises, can be visualized directly on the membrane using reagents (e.m. chloro-naphthol and hydrogen peroxide in Tris buffer) which deposit a coloured production onto the membrane, reflecting the distribution of peroxidase in the tissue section. Alternatively, if an antibody is available for the enzyme of involvement, its location can be visualized, after printing, by immunoblotting. The excess adsorption-sites on the membrane should be blocked with milk-protein (casein) or bovine serum albumin, before being probed with the principal-antibody and visualized with the enzyme-conjugated secondary-antibody (meet to a higher place). The location of the enzyme is indicated by a comparison of the results with ones obtained with a general protein stain.

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Chemosynthesis☆⁎⁎⁎

Alex Enrich-Prast , ... Camila Negrão Signori , in Reference Module in World Systems and Environmental Sciences, 2022

Chemosynthesis and carbon cycling

The highly stratified distribution of costless-living chemosynthetic microorganisms implies that intensive rates of chemosynthesis can exist spatially restricted. In some systems, chemosynthetic processes appear to account for a major share of the total carbon fixation and may exceed ninety% of the total carbon fixation under certain conditions (Table 3). The highest rates take been reported for saline, sulfide-rich environments, such as mono- or meromictic lakes with haloclines. Lakes fed by sulfide-rich groundwater also take high rates of chemosynthesis. Saline inland waters with haloclines may dominate globally in terms of water volume, especially if the Caspian Bounding main, Lake Baikal, the African rift lakes, and big estuaries such as the Baltic Sea are included in the bookkeeping. However, inland waters without haloclines and with moderate to low concentrations of sulfide are more arable past numbers. The limited data from such non-saline inland waters makes it unclear to what extent chemosynthesis contributes to the total CO₂ fixation.

The contribution of chemosynthesis to overall carbon fixation in aquatic ecosystems is express by the availability of electron donor substrates, e.chiliad., sulfide, ammonium, etc. In almost inland waters, the electron donors that are the energy source for chemosynthesis typically originate from the deposition of organic thing. Organic matter is typically produced by photosynthesis, either in the aquatic system itself or in the terrestrial surroundings transported to the aquatic environment. Hence, from an energetic point of view, most chemosynthesis in inland waters is indirectly driven past sunlight energy, given the dependence of chemosynthesis on photosynthesis supplying organic textile (Fig. 5). An exception would exist systems with an all-encompassing supply of electron donors from hydrothermal or geochemical external sources (Yang et al., 2011). Therefore, chemosynthesis should only be able to boss carbon fixation relative to aquatic photosynthesis in (1) systems receiving substantial input of organic matter from the surround, or (two) systems with large inputs of reduced substrate compounds directly suitable as electron donors, due east.g., waters receiving reduced compounds of geochemical origin such equally hot springs or some saline sulfide-rich lakes.

In add-on to chemosynthesis, heterotrophic inorganic carbon uptake has been reported for a wide range of organisms from prokaryotes and fungi to vertebrates, compensating for dependence on organic matter (Braun et al., 2021). More twenty carboxylases are known to class an integral function of the central and peripheral metabolic pathways of heterotrophic metabolism, east.g., in gluconeogenesis, the synthesis of fatty acids, amino acids, vitamins, nucleotides, the absorption of leucine, and anaplerosis. The most important CO₂ fixation pathway in all organisms is anaplerosis, which replaces endogenous components of the tricarboxylic acid (TCA) cycle with either inter- or extra-cellular exogenous products. Although dark carbon incorporation appears to part at low levels in heterotrophic bacteria, it has been suggested that the carboxylase activity increases in situations of organic matter deficiency and slow growth (Moran and Miller, 2007). So, these processes may significantly contribute to the total night carbon fixation.

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Synthesis: Carbon With Iii or Iv Attached Heteroatoms

J. Barluenga , ... M. Tomás , in Comprehensive Organic Functional Group Transformations 2, 2005

6.18.one.1.9 From sulfur-transfer reagents

The direct introduction of sulfur from S₈ into diaminocarbenes—the and then-called Arduengo carbene ligands—can be regarded as a useful entry into cyclic thioureas. Thus, Bildstein and co-workers have reported the preparation of imidazolinethiones, imidazolethiones, and benzimidazolethiones by treatment of the respective azolium salts with base and elemental sulfur (Scheme 37) <1999OM4325, 1999JOM(572)177>.

The synthesis of 4-(4-fluorophenyl)-five-(pyridin-4-yl)imidazole-two-thiones, whose alkylthioimidazoles are inhibitors of p38 MAP kinase, can be carried out in moderate to good yields by transfer of sulfur from sodium (4-chlorophenyl)methanethiolate to 2-chloroimidazoles as outlined in Scheme 38 <2002AG(E)2290>.

The employment of ammonium sulfide for a convenient cyclization of α-cyano-α-(dichloromethyleneimino)alkanoic acids, bachelor from the corresponding isocyanides and chlorine, into 5,5-disubstituted 2,four-dithiohydantoins has been described a few years ago ( Scheme 39) <1998S1437>. The reaction is proposed to occur by addition of sulfide and cyclization to a thiazole band followed by ring opening and new closure.

In 1998 thioketones were first developed as efficient sulfur transfer agents towards azole North-oxides providing a new constructed method for the thiourea office (Scheme twoscore) <1998HCA1585>. Thus, substituted imidazole three-oxides react with some thioketones (2,two,4,iv-tetramethyl-cyclobuta-i,three-dithione, 2,2,4,4-tetramethyl–1-thioxo-cyclobutan-ii-one, and adamantine-2-thione) to give imidazole-ii(3H)-thiones in high yield. Triazole oxides tin can also be transformed equally well into triazolethiones.

Taking advantage of this procedure, Laufer and co-workers <2002AG(E)2290> have synthesized a structurally diverse imidazole thiones during their studies directed to develop new inhibitors of p38 MAP kinase with a 4,v-disubstituted alkylthioimidazole framework (Scheme 41). The required imidazole oxides are obtained in high yields by refluxing in ethanol a mixture of 1-(iv-fluorophenyl)-2-(pyridin-4-yl)hydroximinoethan-2-one and the respective i,3,5-trisubstituted hexahydro-1,3,5-triazine.

In the course of their studies of adenosine-derived monomeric edifice blocks for new oligonucleosides, Gunji and Vasella <2000HCA1331> showed the ability of N-phenylthiourea as sulfur-transfer agent to 2-halogenoimidazoles (Scheme 42). Thus, the 2-chloro and 2-iodo nucleosides were transformed into the corresponding thioxo nucleosides upon heating with Due north-phenylthiourea at 60 °C.

Molina and co-workers <2000TL4895> have reported a rather unexpected sulfur-transfer reaction from carbon disulfide which is the basis of a new synthesis of dihydroquinazoline-2-thiones (Scheme 43). The process comprises the intramolecular heteroconjugate addition of aromatic carbodiimides bearing an o-substituted α,β-unsaturated carbonyl fragment promoted by the carbon disulfide/tetrabutylammonium fluoride. The mechanism proposed past the authors nicely accounts for the circuitous transformation and involves cyclization induced by set on of the Due south-nucleophile fluorodithioformate, generated from CS_ii-TBAF, followed by thioacyl fluoride hydrolysis and fragmentation to the thione group and C(S)O.

Finally, North,N-unsubstituted thioureas are attainable in moderate-to-high yield by sulfur transfer from LiAlHSH, generated in situ past mixing LAH and sulfur, to chloroamidines, as depicted in Scheme 44 <2001TL6333>.

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