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Chemical Test
In chemistry, a chemical test is a qualitative property, qualitative or Quantitative property, quantitative procedure designed to identify, quantify, or characterise a chemical compound or substituent, chemical group. Purposes Chemical testing might have a variety of purposes, such as to: * Determine if, or verify that, the requirements of a specification, regulation, or contract are met * Decide if a new product development program is on track: Demonstrate proof of concept * Demonstrate the utility of a proposed patent * Determine the interactions of a sample with other known substances * Determine the composition of a sample * Provide Technical standard, standard data for other scientific, medical, and Quality assurance functions * Validate suitability for end-use * Provide a basis for Technical communication * Provide a technical means of comparison of several options * Provide evidence in legal proceedings Biochemical tests * Clinistrips quantitatively test for sugar in uri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemistry
Chemistry is the science, scientific study of the properties and behavior of matter. It is a natural science that covers the Chemical element, elements that make up matter to the chemical compound, compounds made of atoms, molecules and ions: their composition, structure, properties, behavior and the changes they undergo during a Chemical reaction, reaction with other Chemical substance, substances. Chemistry also addresses the nature of chemical bonds in chemical compounds. In the scope of its subject, chemistry occupies an intermediate position between physics and biology. It is sometimes called the central science because it provides a foundation for understanding both Basic research, basic and Applied science, applied scientific disciplines at a fundamental level. For example, chemistry explains aspects of plant growth (botany), the formation of igneous rocks (geology), how atmospheric ozone is formed and how environmental pollutants are degraded (ecology), the properties ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clinistrip
Clinistrip, also known as CLINISTIX or the brand name Diastix, are specific clinical sticks for the detection of glucose. Clinistrip consists of a section that contains glucose oxidase that has been dried onto the paper pad. It is an example of a biosensor-based test for glucose. This is similar to the glucose oxidase assay, as the glucose in the urine, once the stick has been dipped into the urine, is oxidized to yield gluconic acid and hydrogen peroxide. The enzyme peroxidase is also present on the pad, and it utilizes the hydrogen peroxide produced to oxidise a dye A dye is a colored substance that chemically bonds to the substrate to which it is being applied. This distinguishes dyes from pigments which do not chemically bind to the material they color. Dye is generally applied in an aqueous solution and ... that results in a colour change. The intensity of the colour change on the pad reflects the amount of glucose present in the urine. Biochemistry methods Chemical t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seliwanoff's Test
Seliwanoff’s test is a chemical test which distinguishes between aldose and ketose sugars. If the sugar contains a ketone group, it is a ketose. If a sugar contains an aldehyde group, it is an aldose. This test relies on the principle that, when heated, ketoses are more rapidly dehydrated than aldoses. It is named after Theodor Seliwanoff, the chemist that devised the test. When added to a solution containing ketoses, a red color is formed rapidly indicating a positive test. When added to a solution containing aldoses, a slower forming light pink is observed instead. The reagents consist of resorcinol and concentrated hydrochloric acid: * The acid hydrolysis of polysaccharide and oligosaccharide ketoses yields simpler sugars followed by furfural.Abramoff, Peter; Thomson, Robert (1966). An experimental approach to biology. WH Freeman & Company, San Francisco. p. 47. * The dehydrated ketose then reacts with two equivalents of resorcinol in a series of condensation reactions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zimmermann Test
A Meisenheimer complex or Jackson–Meisenheimer complex in organic chemistry is a 1:1 reaction adduct between an arene carrying electron withdrawing groups and a nucleophile. These complexes are found as reactive intermediates in nucleophilic aromatic substitution but stable and isolated Meisenheimer salts are also known. Background The early development of this type of complex takes place around the turn of the 19th century. In 1886 Janovski observed an intense violet color when he mixed ''meta''-dinitrobenzene with an alcoholic solution of alkali. In 1895 Cornelis Adriaan Lobry van Troostenburg de Bruyn investigated a red substance formed in the reaction of trinitrobenzene with potassium hydroxide in methanol. In 1900 Jackson and Gazzolo reacted trinitroanisole with sodium methoxide and proposed a quinoid structure for the reaction product. : In 1902 Jakob Meisenheimer observed that by acidifying their reaction product, the starting material was recovered. With three elec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amino Acid
Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha amino acids appear in the genetic code. Amino acids can be classified according to the locations of the core structural functional groups, as Alpha and beta carbon, alpha- , beta- , gamma- or delta- amino acids; other categories relate to Chemical polarity, polarity, ionization, and side chain group type (aliphatic, Open-chain compound, acyclic, aromatic, containing hydroxyl or sulfur, etc.). In the form of proteins, amino acid '' residues'' form the second-largest component (water being the largest) of human muscles and other tissues. Beyond their role as residues in proteins, amino acids participate in a number of processes such as neurotransmitter transport and biosynthesis. It is thought that they played a key role in enabling life ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Van Slyke Determination
The Van Slyke determination is a chemical test for the determination of amino acids containing a primary amine group. It is named after the biochemist Donald Dexter Van Slyke (1883-1971). One of Van Slyke's first professional achievements was the quantification of amino acids by the Van Slyke determination reaction. To quantify aliphatic amino acids, the sample is diluted in glycerol and then treated with a solution of sodium nitrite, water and acetic acid. The resulting diazotisation reaction produces nitrogen gas which can be observed qualitatively or measured quantitatively. Van Slyke Reaction: R-NH2 + HONO -> ROH + N2 + H2O In addition, Van Slyke developed the so-called Van Slyke apparatus, which can be used to determine the concentration of respiratory gases in the blood, especially the concentration of sodium bicarbonate. This was of high importance to be able to recognize a beginning acidosis in diabetic patients as early as possible, in order to start alkali treatmen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Starch
Starch or amylum is a polymeric carbohydrate consisting of numerous glucose units joined by glycosidic bonds. This polysaccharide is produced by most green plants for energy storage. Worldwide, it is the most common carbohydrate in human diets, and is contained in large amounts in staple foods such as wheat, potatoes, maize (corn), rice, and cassava (manioc). Pure starch is a white, tasteless and odorless powder that is insoluble in cold water or alcohol. It consists of two types of molecules: the linear and helical amylose and the branched amylopectin. Depending on the plant, starch generally contains 20 to 25% amylose and 75 to 80% amylopectin by weight. Glycogen, the energy reserve of animals, is a more highly branched version of amylopectin. In industry, starch is often converted into sugars, for example by malting. These sugars may be fermented to produce ethanol in the manufacture of beer, whisky and biofuel. In addition, sugars produced from processed starch are used ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tincture Of Iodine
Tincture of iodine, iodine tincture, or weak iodine solution is an antiseptic. It is usually 2 to 7% elemental iodine, along with potassium iodide or sodium iodide, dissolved in a mixture of ethanol and water. Tincture solutions are characterized by the presence of alcohol. It was used from 1908 in pre-operative skin preparation by Italian surgeon Antonio Grossich. In the United Kingdom, the development of an iodine solution for skin sterilisation was pioneered by Lionel Stretton. The ''British Medical Journal'' published the detail of his work at Kidderminster Infirmary in 1909. Stretton used a much weaker solution than that used by Grossich. He claimed in 1915 that Grossich had been using a liquid akin to Liquor Iodi Fortis, and that it was he, Stretton, who had introduced the method using Tincture of Iodine British Pharmacopoeia, BP which came to be used across the world. USP formulas USP Tincture of Iodine is defined in the U.S. National Formulary (NF) as containing in ea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saliva
Saliva (commonly referred to as spit) is an extracellular fluid produced and secreted by salivary glands in the mouth. In humans, saliva is around 99% water, plus electrolytes, mucus, white blood cells, epithelial cells (from which DNA can be extracted), enzymes (such as lipase and amylase), antimicrobial agents (such as secretory IgA, and lysozymes). The enzymes found in saliva are essential in beginning the process of digestion of dietary starches and fats. These enzymes also play a role in breaking down food particles entrapped within dental crevices, thus protecting teeth from bacterial decay. Saliva also performs a lubricating function, wetting food and permitting the initiation of swallowing, and protecting the oral mucosa from drying out. Various animal species have special uses for saliva that go beyond predigestion. Some swifts use their gummy saliva to build nests. ''Aerodramus'' nests form the basis of bird's nest soup. Cobras, vipers, and certain other membe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phadebas
Phadebas is a synthetic biochemical substrate used for both qualitative and quantitative assessment of the α-amylase enzyme. Its active component is DSM-P, microspheres in which a blue dye has been chemically bound. When the substrate is digested by the amylase enzyme in solution, it releases that blue dye at a rate proportional to the quantity of the enzyme present. It is used in a range of applications from quality control tests for food & beverages to detection of saliva stains in forensic investigations. History The "Phadebas Amylase Test" (PAT) was the first product developed by Pharmacia Diagnostics and was launched in 1970. The name Phadebas is an abbreviation of Pharmacia Diagnostics Biologically Active Substances. In the 70s, PAT was used in hospitals worldwide as an in vitro diagnostics test for acute pancreatitis but the application was later outrivaled by automatic analysis systems. PAT is no longer marketed for the IVD-market and no longer upholds its EC-certifi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salicylate Testing
Salicylate testing is a category of drug testing that is focused on detecting salicylates such as acetysalicylic acid for either biochemical or medical purposes. Analytical Salicylates can be identified by GC/MS, proton NMR, and IR. In vitro One of the first ''in vitro'' tests for aspirin was through the Trinder reaction. Aqueous ferric chloride was added to a urine sample, and the formation of the iron complex turned the solution purple. This test was not specific to acetylsalicylic acid but would occur in the presence of any phenol or enol. The downfall of this test occurs in the presence of hyperbilirubinemia or elevated bilirubin. When the level of bilirubin exceeds 1 mg/ dl, a false positive could occur. Enzyme Specific Assay The current ''in vitro'' testing utilizes molecule specific methods of detecting salicylates. Immunoassay Another identification mechanism is through immunoassay. Abbott Labs' AxSYM is an immunoassay device utilizing Fluorescence Pol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blood
Blood is a body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells, and transports metabolic waste products away from those same cells. Blood in the circulatory system is also known as ''peripheral blood'', and the blood cells it carries, ''peripheral blood cells''. Blood is composed of blood cells suspended in blood plasma. Plasma, which constitutes 55% of blood fluid, is mostly water (92% by volume), and contains proteins, glucose, mineral ions, hormones, carbon dioxide (plasma being the main medium for excretory product transportation), and blood cells themselves. Albumin is the main protein in plasma, and it functions to regulate the colloidal osmotic pressure of blood. The blood cells are mainly red blood cells (also called RBCs or erythrocytes), white blood cells (also called WBCs or leukocytes) and platelets (also called thrombocytes). The most abundant cells in vertebrate blo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
