|
Bromocresol Purple
Bromocresol purple (BCP) or 5′,5″-dibromo-''o''-cresolsulfophthalein, is a dye of the triphenylmethane family (triarylmethane dyes) and a pH indicator. It is colored yellow below pH 5.2, and violet above pH 6.8. In its cyclic sulfonate ester form, it has a p''K''a value of 6.3, and is usually prepared as a 0.04% aqueous solution. Uses Bromocresol purple is used in medical laboratories to measure albumin. Use of BCP in this application may provide some advantage over older methods using bromocresol green. In microbiology, it is used for staining dead cells based on their acidity, and for the isolation and assaying of lactic acid bacteria. In photographic processing, it can be used as an additive to acid stop baths to indicate that the bath has reached neutral pH and needs to be replaced. Bromocresol purple milk solids glucose agar is used as a medium used to distinguish dermatophytes from bacteria and other organisms in cases of ringworm fungus ('' T. verrucosum'') infest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triphenylmethane
Triphenylmethane, or triphenyl methane, is the hydrocarbon with the formula (C6H5)3CH. This colorless solid is soluble in nonpolar organic solvents and not in water. Triphenylmethane is the basic skeleton of many synthetic dyes called triarylmethane dyes, many of them are pH indicators, and some display fluorescence. A trityl group in organic chemistry is a triphenylmethyl group Ph3C, e.g. triphenylmethyl chloride (trityl chloride) and the triphenylmethyl radical (trityl radical). Preparation Triphenylmethane was first synthesized in 1872 by the German chemist August Kekulé and his Belgian student Antoine Paul Nicolas Franchimont (1844–1919) by heating diphenylmercury (Hg(C6H5)2, ''Quecksilberdiphenyl'') with benzal chloride (C6H5CHCl2, ''Benzylenchlorid''). Triphenylmethane can be synthesized by Friedel–Crafts reaction from benzene and chloroform with aluminium chloride catalyst: :3 C6H6 + CHCl3 → Ph3CH + 3 HCl Alternatively, benzene may react with carbon tetrachloride us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dermatophyte
Dermatophyte (from Greek '' derma'' "skin" (GEN ''dermatos'') and ''phyton'' "plant") is a common label for a group of fungus of ''Arthrodermataceae'' that commonly causes skin disease in animals and humans. Traditionally, these anamorphic (asexual or imperfect fungi) mold genera are: ''Microsporum'', ''Epidermophyton'' and ''Trichophyton''. There are about 40 species in these three genera. Species capable of reproducing sexually belong in the teleomorphic genus Arthroderma, of the Ascomycota (see Teleomorph, anamorph and holomorph for more information on this type of fungal life cycle). As of 2019 a total of nine genera are identified and new phylogenetic taxonomy has been proposed. Dermatophytes cause infections of the skin, hair, and nails, obtaining nutrients from keratinized material. The organisms colonize the keratin tissues causing inflammation as the host responds to metabolic byproducts. Colonies of dermatophytes are usually restricted to the nonliving cornified laye ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenol Dyes
Phenol (also called carbolic acid) is an aromatic organic compound with the molecular formula . It is a white crystalline solid that is volatile. The molecule consists of a phenyl group () bonded to a hydroxy group (). Mildly acidic, it requires careful handling because it can cause chemical burns. Phenol was first extracted from coal tar, but today is produced on a large scale (about 7 billion kg/year) from petroleum-derived feedstocks. It is an important industrial commodity as a precursor to many materials and useful compounds. It is primarily used to synthesize plastics and related materials. Phenol and its chemical derivatives are essential for production of polycarbonates, epoxies, Bakelite, nylon, detergents, herbicides such as phenoxy herbicides, and numerous pharmaceutical drugs. Properties Phenol is an organic compound appreciably soluble in water, with about 84.2 g dissolving in 1000 mL (0.895 M). Homogeneous mixtures of phenol and water at phenol to wate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PH Indicators
A pH indicator is a halochromism, halochromic chemical compound added in small amounts to a Solution (chemistry), solution so the pH (acidity or Base (chemistry), basicity) of the solution can be determined visually or spectroscopically by changes in absorption and/or emission properties. Hence, a pH indicator is a Chemical substance, chemical detector for hydronium ions (H3O+) or hydrogen ions (H+) in the Acid-base reaction theories, Arrhenius model. Normally, the indicator causes the color of the solution to change depending on the pH. Indicators can also show change in other physical properties; for example, olfactory indicators show change in their odor. The pH value of a neutral solution is 7.0 at 25°C (Standard_conditions_for_temperature_and_pressure#Standard_laboratory_conditions, standard laboratory conditions). Solutions with a pH value below 7.0 are considered acidic and solutions with pH value above 7.0 are basic. Since most naturally occurring Organic compound, organ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metacresol Purple
Metacresol purple or ''m''-cresol purple, also called ''m''-cresolsulfonphthalein, is a triarylmethane dye and a pH indicator. It is used as a capnographic indicator for detecting detect end-tidal carbon dioxide to ensure successful tracheal intubation in an emergency. It can be used to measure the pH in subzero temperatures of saline or hypersaline media. In colorimetric capnography, the indicator is incorporated in an aqueous matrix that provides a pH just above the indicator's colour change. When exposed to carbon dioxide (CO2), it undergoes a colour change from purple to yellow, because when CO2 dissolves in the matrix, it forms carbonic acid. In chemistry, it has two useful indicator ranges: * pH 1.2–2.8: red to yellow * pH 7.4–9.0: yellow to purple See also * Bromocresol purple Bromocresol purple (BCP) or 5′,5″-dibromo-''o''-cresolsulfophthalein, is a dye of the triphenylmethane family ( triarylmethane dyes) and a pH indicator. It is colored yellow below pH 5.2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sultone
In organosulfur chemistry, a sulfonate is a salt or ester of a sulfonic acid. It contains the functional group , where R is an organic group. Sulfonates are the conjugate bases of sulfonic acids. Sulfonates are generally stable in water, non-oxidizing, and colorless. Many useful compounds and even some biochemicals feature sulfonates. Sulfonate salts Anions with the general formula are called sulfonates. They are the conjugate bases of sulfonic acids with formula . As sulfonic acids tend to be strong acids, the corresponding sulfonates are weak bases. Due to the stability of sulfonate anions, the cations of sulfonate salts such as scandium triflate have application as Lewis acids. A classic preparation of sulfonates is the Strecker sulfite alkylation, in which an alkali sulfite salt displaces a halide, typically in the presence of an iodine catalyst: :RX + M2SO3 -> RSO3M + MX An alternative is the condensation of a sulfonyl halide with an alcohol in pyridine: :ROH + R' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Equilibrium
In a chemical reaction, chemical equilibrium is the state in which both the reactants and products are present in concentrations which have no further tendency to change with time, so that there is no observable change in the properties of the system. This state results when the forward reaction proceeds at the same rate as the reverse reaction. The reaction rates of the forward and backward reactions are generally not zero, but they are equal. Thus, there are no net changes in the concentrations of the reactants and products. Such a state is known as dynamic equilibrium. Historical introduction The concept of chemical equilibrium was developed in 1803, after Berthollet found that some chemical reactions are reversible. For any reaction mixture to exist at equilibrium, the rates of the forward and backward (reverse) reactions must be equal. In the following chemical equation, arrows point both ways to indicate equilibrium. A and B are reactant chemical species, S and T are p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Star Publishing Company
A star is an astronomical object comprising a luminous spheroid of plasma held together by its gravity. The nearest star to Earth is the Sun. Many other stars are visible to the naked eye at night, but their immense distances from Earth make them appear as fixed points of light. The most prominent stars have been categorised into constellations and asterisms, and many of the brightest stars have proper names. Astronomers have assembled star catalogues that identify the known stars and provide standardized stellar designations. The observable universe contains an estimated to stars. Only about 4,000 of these stars are visible to the naked eye, all within the Milky Way galaxy. A star's life begins with the gravitational collapse of a gaseous nebula of material composed primarily of hydrogen, along with helium and trace amounts of heavier elements. Its total mass is the main factor determining its evolution and eventual fate. A star shines for most of its active lif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trichophyton Verrucosum
''Trichophyton verrucosum'', commonly known as the cattle ringworm fungus, is a dermatophyte largely responsible for fungal skin disease in cattle, but is also a common cause of ringworm in donkeys, dogs, goat, sheep, and horses. It has a worldwide distribution, however human infection is more common in rural areas where contact with animals is more frequent, and can cause severe inflammation of the afflicted region. ''Trichophyton verrucosum'' was first described by Emile Bodin in 1902. Growth and morphology ''Trichophyton verrucosum'' is very slow-growing compared to other dermatophytes. In culture, it is characterized by being flat, white/cream colour, having an occasional dome, with a glabrous texture, known as the variant ''album'', however other variations are also found: ''T. verrucosum'' var. ''ochraceum'' has a flat, yellow, glabrous colony; ''T. verrucosum'' var. ''discoides'' has a gray-white, flat, and tomentose colony; and ''T. verrucosum'' var. ''autotrophicum'' is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ringworm
Dermatophytosis, also known as ringworm, is a fungal infection of the skin. Typically it results in a red, itchy, scaly, circular rash. Hair loss may occur in the area affected. Symptoms begin four to fourteen days after exposure. Multiple areas can be affected at a given time. About 40 types of fungus can cause ringworm. They are typically of the ''Trichophyton'', ''Microsporum'', or ''Epidermophyton'' type. Risk factors include using public showers, contact sports such as wrestling, excessive sweating, contact with animals, obesity, and poor immune function. Ringworm can spread from other animals or between people. Diagnosis is often based on the appearance and symptoms. It may be confirmed by either culturing or looking at a skin scraping under a microscope. Prevention is by keeping the skin dry, not walking barefoot in public, and not sharing personal items. Treatment is typically with antifungal creams such as clotrimazole or miconazole. If the scalp is involved, ant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
