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Bismarck Brown Y
Bismarck brown Y also called C.I. 21000 and C.I. Basic Brown 1, is a diazo dye with the idealized formula H2N)2C6H3N2sub>2C6H4. The dye is a mixture of closely related compounds. It was one of the earliest azo dyes, being described in 1863 by German chemist Carl Alexander von Martius. It is used in histology for staining tissues. Synthesis The dye is simple to prepare because the diamine serves both as a source of the diazonium cation and as the coupling partner in the azo coupling reaction. The synthesis is thought to start with double diazotization of 1,3-phenylenediamine: :(H2N)2C6H4 + 2 H+ + 2 HNO2 → 6H4(N2)2sup>2+ + 2 H2O It is assumed that this bis(diazonium) ion subsequently attacks two equivalents of 1,3-phenylenediamine: :2 (H2N)2C6H4 + 6H4(N2)2sup>2+ → 2 H+ + H2N)2C6H3N2sub>2C6H4 In some cases, toluenediamines are used in addition to the phenylenediamine. Furthermore, the resulting dye is thought to consist of oligomers with three or more ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colour Index International
Colour Index International is a reference database jointly maintained by the Society of Dyers and Colourists and the American Association of Textile Chemists and Colorists. It currently contains over 27,000 individual products listed under 13,000 Colour Index Generic Names. It was first printed in 1925 but is now published solely on the World Wide Web. The index serves as a common reference database of manufactured colour products and is used by manufacturers and consumers, such as artists and decorators. Colorants (both dyes and pigments) are listed using a dual classification which use the Colour Index Generic Name (the prime identifier) and Colour Index Constitution Numbers. These numbers are prefixed with C.I. or CI, for example, C.I. 15510. (This abbreviation is sometimes mistakenly thought to be CL, due to the font used to display it.) A detailed record of products available on the market is presented under each Colour Index reference. For each product name, Colour Index ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bone
A bone is a rigid organ that constitutes part of the skeleton in most vertebrate animals. Bones protect the various other organs of the body, produce red and white blood cells, store minerals, provide structure and support for the body, and enable mobility. Bones come in a variety of shapes and sizes and have complex internal and external structures. They are lightweight yet strong and hard and serve multiple functions. Bone tissue (osseous tissue), which is also called bone in the uncountable sense of that word, is hard tissue, a type of specialized connective tissue. It has a honeycomb-like matrix internally, which helps to give the bone rigidity. Bone tissue is made up of different types of bone cells. Osteoblasts and osteocytes are involved in the formation and mineralization of bone; osteoclasts are involved in the resorption of bone tissue. Modified (flattened) osteoblasts become the lining cells that form a protective layer on the bone surface. The mineralize ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acid-fast
Acid-fastness is a physical property of certain bacterial and eukaryotic cells, as well as some sub-cellular structures, specifically their resistance to decolorization by acids during laboratory staining procedures. Once stained as part of a sample, these organisms can resist the acid and/or ethanol-based decolorization procedures common in many staining protocols, hence the name ''acid-fast''. The mechanisms of acid-fastness vary by species, although the most well-known example is in the genus ''Mycobacterium'', which includes the species responsible for tuberculosis and leprosy. The acid-fastness of ''Mycobacteria'' is due to the high mycolic acid content of their cell walls, which is responsible for the staining pattern of poor absorption followed by high retention. Some bacteria may also be partially acid-fast, such as ''Nocardia''. Acid-fast organisms are difficult to characterize using standard microbiological techniques, though they can be stained using concentrated dyes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Victoria Blue R
Victoria blue R is a dye with formula C29H32N3Cl. It has a blue colour that changes to yellow at low pH values. Physical data Fastness The dye exerts a high light fastness and washing fastness. UV/VIS absorption Victoria Blue R has an absorption peak of around 610nm. {{organic-compound-stub Chlorides Triarylmethane dyes Dimethylamino compounds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Counterstain
A counterstain is a stain with colour contrasting to the principal stain, making the stained structure easily visible using a microscope. Examples include the malachite green counterstain to the fuchsine stain in the Gimenez staining technique and the eosin counterstain to haematoxylin in the H&E stain. In Gram staining, crystal violet stains only Gram-positive bacteria, and safranin counterstain is applied which stains all cells, allowing the identification of Gram-negative bacteria as well. An alternative method uses dilute carbofluozide. Counterstains are sometimes used to separate animals from organic detritus In biology, detritus () is dead particulate organic material, as distinguished from dissolved organic material. Detritus typically includes the bodies or fragments of bodies of dead organisms, and fecal material. Detritus typically hosts comm ... in microbiology studies. References Staining {{pathology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Papanicolaou Stain
Papanicolaou stain (also Papanicolaou's stain and Pap stain) is a multichromatic (multicolored) cytological staining technique developed by George Papanicolaou in 1942. The Papanicolaou stain is one of the most widely used stains in cytology, where it is used to aid pathologists in making a diagnosis. Although most notable for its use in the detection of cervical cancer in the Pap test or Pap smear, it is also used to stain non- gynecological specimen preparations from a variety of bodily secretions and from small needle biopsies of organs and tissues. Papanicolaou published three formulations of this stain in 1942, 1954, and 1960. Usage Pap staining is used to differentiate cells in smear preparations (in which samples are spread or smeared onto a glass microscope slide) from various bodily secretions and needle biopsies; the specimens may include gynecological smears (Pap smears), sputum, brushings, washings, urine, cerebrospinal fluid, abdominal fluid, pleural fluid, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Feulgen Stain
Feulgen stain is a staining technique discovered by Robert Feulgen and used in histology to identify chromosomal material or DNA in cell specimens. It is darkly stained. It depends on acid hydrolysis of DNA, therefore fixating agents using strong acids should be avoided. The specimen is subjected to warm (60 °C) hydrochloric acid, then to Schiff reagent. In the past, a sulfite rinse followed, but this is now considered unnecessary. Optionally, the sample can be counterstained with Light Green SF yellowish. Finally, it is dehydrated with ethanol, cleared with xylene, and mounted in a resinous medium. DNA should be stained red. The background, if counterstained, is green. The Feulgen reaction is a semi-quantitative technique. If the only aldehydes remaining in the cell are those produced from the hydrolysis of DNA, then the technique is quantitative for DNA. It is possible to use an instrument known as a microdensitometer or microspectrophotometer to actually measure the intens ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cellulose
Cellulose is an organic compound with the formula , a polysaccharide consisting of a linear chain of several hundred to many thousands of β(1→4) linked D-glucose units. Cellulose is an important structural component of the primary cell wall of green plants, many forms of algae and the oomycetes. Some species of bacteria secrete it to form biofilms. Cellulose is the most abundant organic polymer on Earth. The cellulose content of cotton fiber is 90%, that of wood is 40–50%, and that of dried hemp is approximately 57%. Cellulose is mainly used to produce paperboard and paper. Smaller quantities are converted into a wide variety of derivative products such as cellophane and rayon. Conversion of cellulose from energy crops into biofuels such as cellulosic ethanol is under development as a renewable fuel source. Cellulose for industrial use is mainly obtained from wood pulp and cotton. Some animals, particularly ruminants and termites, can digest cellulose wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Periodic Acid-Schiff Stain
Periodicity or periodic may refer to: Mathematics * Bott periodicity theorem, addresses Bott periodicity: a modulo-8 recurrence relation in the homotopy groups of classical groups * Periodic function, a function whose output contains values that repeat periodically * Periodic mapping Physical sciences * Periodic table of chemical elements * Periodic trends, relative characteristics of chemical elements observed * Redshift periodicity, astronomical term for redshift quantization Other uses * Fokker periodicity blocks, which mathematically relate musical intervals * Periodic acid, a compound of iodine * Principle of periodicity, a concept in generally accepted accounting principles * Quasiperiodicity, property of a system that displays irregular periodicity See also * Aperiodic (other) * Cycle (other) * Frequency (other) * Period (other) * Periodical * Seasonality In time series data, seasonality is the presence of variations that occur a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schiff Reagent
: The Schiff test is an early organic chemistry named reaction developed by Hugo Schiff, and is a relatively general chemical test for detection of many organic aldehydes that has also found use in the staining of biological tissues. The Schiff reagent is the reaction product of a dye formulation such as fuchsin and sodium bisulfite; pararosaniline (which lacks an aromatic methyl group) and new fuchsin (which is uniformly mono-methylated ''ortho'' to the dye's amine functionalities) are not dye alternatives with comparable detection chemistry. In its use as a qualitative test for aldehydes, the unknown sample is added to the decolorized Schiff reagent; when aldehyde is present a characteristic magenta color develops. Schiff-type reagents are used for various biological tissue staining methods, e.g. Feulgen stain and periodic acid-Schiff stain. Human skin also contains aldehyde functional groups in the termini of saccharides and so is stained as well. Mechanism Fuchsin solut ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cartilage
Cartilage is a resilient and smooth type of connective tissue. In tetrapods, it covers and protects the ends of long bones at the joints as articular cartilage, and is a structural component of many body parts including the rib cage, the neck and the bronchial tubes, and the intervertebral discs. In other taxa, such as chondrichthyans, but also in cyclostomes, it may constitute a much greater proportion of the skeleton. It is not as hard and rigid as bone, but it is much stiffer and much less flexible than muscle. The matrix of cartilage is made up of glycosaminoglycans, proteoglycans, collagen fibers and, sometimes, elastin. Because of its rigidity, cartilage often serves the purpose of holding tubes open in the body. Examples include the rings of the trachea, such as the cricoid cartilage and carina. Cartilage is composed of specialized cells called chondrocytes that produce a large amount of collagenous extracellular matrix, abundant ground substance that is rich in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diazo Dye
Azo dyes are organic compounds bearing the functional group R−N=N−R′, in which R and R′ are usually aryl and substituted aryl groups. They are a commercially important family of azo compounds, i.e. compounds containing the C-N=N-C linkage. Azo dyes are synthetic dyes and do not occur naturally. Most azo dyes contain only one azo group, but some dyes called "disazo dyes" contain two azo groups, some dyes called "trisazo dyes" contain three azo groups and are or more. Azo dyes comprise 60-70% of all dyes used in food and textile industries. Azo dyes are widely used to treat textiles, leather articles, and some foods. Chemically related derivatives of azo dyes include azo pigments, which are insoluble in water and other solvents. Classes Many kinds of azo dyes are known, and several classification systems exist. Some classes include disperse dyes, metal-complex dyes, reactive dyes, and substantive dyes. Also called direct dyes, substantive dyes are employed fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
