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Radioimmunoassay
A radioimmunoassay (RIA) is an immunoassay that uses radioactive tracer, radiolabeled molecules in a stepwise formation of immune complexes. A RIA is a very sensitive in vitro assay technique used to measure concentrations of substances, usually measuring antigen concentrations (for example, hormone levels in blood) by use of antibody, antibodies. The RIA technique is extremely sensitivity (tests), sensitive and extremely Specificity (tests), specific, and although it requires specialized equipment, it remains among the least expensive methods to perform such measurements. It requires special precautions and licensing, since radioactive substances are used. In contrast, an immunoradiometric assay (IRMA) is an immunoassay that uses radiolabeled molecules but in an immediate rather than stepwise way. A radioallergosorbent test (RAST) is an example of radioimmunoassay. It is used to detect the causative allergen for an allergy. Method Classically, to perform a radioimmunoassay, a k ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ELISA
The enzyme-linked immunosorbent assay (ELISA) (, ) is a commonly used analytical biochemistry assay, first described by Eva Engvall and Peter Perlmann in 1971. The assay is a solid-phase type of enzyme immunoassay (EIA) to detect the presence of a ligand (commonly an amino acid) in a liquid sample using antibodies directed against the ligand to be measured. ELISA has been used as a medical diagnosis, diagnostic tool in medicine, plant pathology, and biotechnology, as well as a quality control check in various industries. In the most simple form of an ELISA, antigens from the sample to be tested are attached to a surface. Then, a matching antibody is applied over the surface so it can bind the antigen. This antibody is linked to an enzyme, and then any unbound antibodies are removed. In the final step, a substance containing the enzyme's Enzyme substrate, substrate is added. If there was binding, the subsequent reaction produces a detectable signal, most commonly a color change. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rosalyn Sussman Yalow
Rosalyn Sussman Yalow (July 19, 1921 – May 30, 2011) was an American medical physicist, and a co-winner of the 1977 Nobel Prize in Physiology or Medicine (together with Roger Guillemin and Andrew Schally) for development of the radioimmunoassay technique. She was the second woman (after Gerty Cori), and the first American-born woman, to be awarded the Nobel Prize in Physiology or Medicine. Biography Childhood Rosalyn Sussman Yalow was born in the Bronx, New York, the daughter of Clara (née Zipper) and Simon Sussman, and was raised in a Jewish household. She went to Walton High School (Bronx), New York City. After high school, she attended the all-female, tuition-free Hunter College, where her mother hoped she would learn to become a teacher. Instead, Yalow decided to study physics. College Yalow knew how to type, and was able to get a part-time position as a secretary to Dr. Rudolf Schoenheimer, a leading biochemist at Columbia University's College of Physicians and Surgeo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immunoassay
An immunoassay (IA) is a biochemical test that measures the presence or concentration of a macromolecule or a small molecule in a solution through the use of an antibody (usually) or an antigen (sometimes). The molecule detected by the immunoassay is often referred to as an "analyte" and is in many cases a protein, although it may be other kinds of molecules, of different sizes and types, as long as the proper antibodies that have the required properties for the assay are developed. Analytes in biological liquids such as blood plasma, serum or urine are frequently measured using immunoassays for medical and research purposes. Immunoassays come in many different formats and variations. Immunoassays may be run in multiple steps with reagents being added and washed away or separated at different points in the assay. Multi-step assays are often called separation immunoassays or heterogeneous immunoassays. Some immunoassays can be carried out simply by mixing the reagents and samples an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tritium
Tritium () or hydrogen-3 (symbol T or H) is a rare and radioactive isotope of hydrogen with a half-life of ~12.33 years. The tritium nucleus (t, sometimes called a ''triton'') contains one proton and two neutrons, whereas the nucleus of the common isotope hydrogen-1 (''protium'') contains one proton and no neutrons, and that of non-radioactive hydrogen-2 ('' deuterium'') contains one proton and one neutron. Tritium is the heaviest particle-bound isotope of hydrogen. It is one of the few nuclides with a distinct name. The use of the name hydrogen-3, though more systematic, is much less common. Naturally occurring tritium is extremely rare on Earth. The atmosphere has only trace amounts, formed by the interaction of its gases with cosmic rays. It can be produced artificially by irradiation of lithium or lithium-bearing ceramic pebbles in a nuclear reactor and is a low-abundance byproduct in normal operations of nuclear reactors. Tritium is used as the energy source in radio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Bronx
The Bronx ( ) is the northernmost of the five Boroughs of New York City, boroughs of New York City, coextensive with Bronx County, in the U.S. state of New York (state), New York. It shares a land border with Westchester County, New York, Westchester County to its north; to its south and west, the New York City borough of Manhattan is across the Harlem River; and to its south and east is the borough of Queens, across the East River. The Bronx, the only New York City borough not primarily located on an island, has a land area of and a population of 1,472,654 at the 2020 United States census, 2020 census. It has the fourth-largest area, fourth-highest population, and third-highest population density of the boroughs.New York State Department of Health''Population, Land Area, and Population Density by County, New York State – 2010'' retrieved on August 8, 2015. The Bronx is divided by the Bronx River into a hillier section in the West Bronx, west, and a flatter East Bronx, easte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bronx Veterans Administration Hospital
The James J. Peters VA Medical Center (also known as the Bronx Veterans Hospital) is a US Department of Veterans Affairs hospital complex located at 130 West Kingsbridge Road in West Fordham, Bronx, Fordham, The Bronx, Bronx, New York City. The hospital is the headquarters of the Veterans Integrated Service Networks New York/New Jersey VA Health Care Network. This network is also the parent network to VA New York Harbor Healthcare System. The campus falls under the jurisdiction of the United States Department of Veterans Affairs Police and the Office of Inspector General (United States), United States Department of Veterans Affairs, Office of Inspector General. History During the American Revolutionary War, the site of the medical center was the location of British '"Fort Number 6" (1777–1779). During the 19th century, the land was part of the estate of Nathaniel Platt Bailey. The site then became the property of the Sisters of Charity of New York who turned it into the B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solomon Berson
Solomon Aaron Berson (April 22, 1918 – April 11, 1972) was an American physician and scientist whose discoveries, mostly together with Rosalyn Yalow, caused major advances in clinical biochemistry.Rall JE. ''Solomon A. Berson''. In "Biographical Memoirs". National Academy of Sciences 1990;59:54-71. Fulltext Five years after Berson's death, Yalow received a Nobel Prize, which cannot be awarded posthumously, for their joint work on the radioimmunoassay. Biography Early life Born in New York City, Berson was a keen musician and chess player. He graduated from the City College of New York in 1938. After failing to obtain a place in medical school he earned an MSc (1939) and an anatomy instructorship at New York University before finally securing a place in NYU medical school in 1941. He completed his degree ( Alpha Omega Alpha) in 1945, and after internships in Boston and two years in the army he returned to New York to do an internal medicine residency at the Bronx Veterans ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agarose
Agarose is a heteropolysaccharide, generally extracted from certain red algae. It is a linear polymer made up of the repeating unit of agarobiose, which is a disaccharide made up of D-galactose and 3,6-anhydro-L-galactopyranose. Agarose is one of the two principal components of agar, and is purified from agar by removing agar's other component, agaropectin. Agarose is frequently used in molecular biology for the separation of large molecules, especially DNA, by electrophoresis. Slabs of agarose gels (usually 0.7 - 2%) for electrophoresis are readily prepared by pouring the warm, liquid solution into a mold. A wide range of different agaroses of varying molecular weights and properties are commercially available for this purpose. Agarose may also be formed into beads and used in a number of chromatographic methods for protein purification. Structure Agarose is a linear polymer with a molecular weight of about 120,000, consisting of alternating D- galactose and 3,6-an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epitope
An epitope, also known as antigenic determinant, is the part of an antigen that is recognized by the immune system, specifically by antibodies, B cells, or T cells. The part of an antibody that binds to the epitope is called a paratope. Although epitopes are usually non-self proteins, sequences derived from the host that can be recognized (as in the case of autoimmune diseases) are also epitopes. The epitopes of protein antigens are divided into two categories, conformational epitopes and linear epitopes, based on their structure and interaction with the paratope. Conformational and linear epitopes interact with the paratope based on the 3-D conformation adopted by the epitope, which is determined by the surface features of the involved epitope residues and the shape or tertiary structure of other segments of the antigen. A conformational epitope is formed by the 3-D conformation adopted by the interaction of discontiguous amino acid residues. In contrast, a linear epitope i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gamma Counter
A gamma counter is an instrument to measure gamma radiation emitted by a radionuclide. Unlike survey meters, gamma counters are designed to measure small samples of radioactive material, typically with automated measurement and movement of multiple samples. Operation Gamma counters are usually scintillation counters. In a typical system, a number of samples are placed in sealed vials or test tubes, and moved along a track. One at a time, they move down inside a shielded detector, set to measure specific energy windows characteristic of the particular isotope. Within this shielded detector there is a scintillation crystal that surrounds the radioactive sample. Gamma rays emitted from the radioactive sample interact with the crystal, are absorbed, and light is emitted. A detector, such as a photomultiplier tube converts the visible light to an electrical signal. Depending on the half-life and concentration of the sample, measurement times may vary from 0.02 minutes to several hours ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supernatant
In an aqueous solution, precipitation is the "sedimentation of a solid material (a precipitate) from a liquid solution". The solid formed is called the precipitate. In case of an inorganic chemical reaction leading to precipitation, the chemical reagent causing the solid to form is called the precipitant. The clear liquid remaining above the precipitated or the centrifuged solid phase is also called the supernate or supernatant. The notion of precipitation can also be extended to other domains of chemistry (organic chemistry and biochemistry) and even be applied to the solid phases (e.g. metallurgy and alloys) when solid impurities segregate from a solid phase. Supersaturation The precipitation of a compound may occur when its concentration exceeds its solubility. This can be due to temperature changes, solvent evaporation, or by mixing solvents. Precipitation occurs more rapidly from a strongly supersaturated solution. The formation of a precipitate can be caused by a che ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Concentration
In chemistry, concentration is the abundance of a constituent divided by the total volume of a mixture. Several types of mathematical description can be distinguished: '' mass concentration'', '' molar concentration'', '' number concentration'', and '' volume concentration''. The concentration can refer to any kind of chemical mixture, but most frequently refers to solutes and solvents in solutions. The molar (amount) concentration has variants, such as normal concentration and osmotic concentration. Dilution is reduction of concentration, e.g. by adding solvent to a solution. The verb to concentrate means to increase concentration, the opposite of dilute. Etymology ''Concentration-'', ''concentratio'', action or an act of coming together at a single place, bringing to a common center, was used in post-classical Latin in 1550 or earlier, similar terms attested in Italian (1589), Spanish (1589), English (1606), French (1632). Qualitative description Often in informal, non- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
