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Resazurin
Resazurin (7-Hydroxy-3''H''-phenoxazin-3-one 10-oxide) is a phenoxazine dye that is weakly fluorescent, nontoxic, cell-permeable, and redox‐sensitive. Resazurin has a blue to purple color (at pH > 6.5) and is used in microbiological, cellular, and enzymatic assays because it can be irreversibly reduced to the pink-colored and highly fluorescent resorufin (7-Hydroxy-3''H''-phenoxazin-3-one). At circum-neutral pH, resorufin can be detected by visual observation of its pink color or by fluorimetry, with an excitation maximum at 530-570 nm and an emission maximum at 580-590 nm. When a solution containing resorufin is submitted to reducing conditions (Eh < -110 mV), almost all resorufin is reversibly reduced to the translucid non-fluorescent dihydroresorufin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interchim
Interchim is a privately owned French company specialized in manufacturing and distribution of reagents, consumables and dedicated instruments for the R&D and industry laboratory in the fields of fine chemistry, chromatography and bio-analysis. It has become a provider of reference methods, products for analytics (analytical chemistry and bioassays) serving research and quality control in the biomedical field, pharmaceutical industry, but also cosmetics and environment. History Interchim was founded by Boch Jean (formerly chemical engineer at Rhone-Poulenc) and Boch Colette in 1970. Their initial activity started with distribution of fine chemicals, then chromatography and Biology. Production was developed as well, in each fields. Affiliate companies were created for production and commercial activities in France, UK (2003), USA (2007) and Instrumentation business (2010). Interchim has now major activity in fine chromatography, fine chemistry and bio-analysis. Leadership in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenoxazine
Phenoxazine is a heterocyclic compound. The structure of phenoxazine consists of an oxazine fused to two benzene rings. It occurs as the central core of a number of naturally occurring chemical compounds such as dactinomycin and litmus. The dyes Nile blue and Nile red are also based on a phenoxazine core. Phenoxazine dyes were once widely used for silk dyeing, but due to their lack of lightfastness they have disappeared over time from the market. However, since their light resistance is significantly better on acrylic fibers, these dyes have experienced a renaissance. See also *Phenothiazine Phenothiazine, abbreviated PTZ, is an organic compound that has the formula S(C6H4)2NH and is related to the thiazine-class of heterocyclic compounds. Derivatives of phenothiazine are highly bioactive and have widespread use and rich history. T ... References {{heterocyclic-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Growth Medium
A growth medium or culture medium is a solid, liquid, or semi-solid designed to support the growth of a population of microorganisms or cells via the process of cell proliferation or small plants like the moss ''Physcomitrella patens''. Different types of media are used for growing different types of cells. The two major types of growth media are those used for cell culture, which use specific cell types derived from plants or animals, and those used for microbiological culture, which are used for growing microorganisms such as bacteria or fungi. The most common growth media for microorganisms are nutrient broths and agar plates; specialized media are sometimes required for microorganism and cell culture growth. Some organisms, termed fastidious organisms, require specialized environments due to complex nutritional requirements. Viruses, for example, are obligate intracellular parasites and require a growth medium containing living cells. Types The most common growth media ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluorescent
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation. It is a form of luminescence. In most cases, the emitted light has a longer wavelength, and therefore a lower photon energy, than the absorbed radiation. A perceptible example of fluorescence occurs when the absorbed radiation is in the ultraviolet region of the electromagnetic spectrum (invisible to the human eye), while the emitted light is in the visible region; this gives the fluorescent substance a distinct color that can only be seen when the substance has been exposed to UV light. Fluorescent materials cease to glow nearly immediately when the radiation source stops, unlike phosphorescent materials, which continue to emit light for some time after. Fluorescence has many practical applications, including mineralogy, gemology, medicine, chemical sensors (fluorescence spectroscopy), fluorescent labelling, dyes, biological detectors, cosmic-ray detection, vacuu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colorimetric
Colorimetry is "the science and technology used to quantify and describe physically the human color perception". It is similar to spectrophotometry, but is distinguished by its interest in reducing spectra to the physical correlates of color perception, most often the CIE 1931 XYZ color space tristimulus values and related quantities. History The Duboscq colorimeter was invented by Jules Duboscq in 1870. Instruments Colorimetric equipment is similar to that used in spectrophotometry. Some related equipment is also mentioned for completeness. * A tristimulus colorimeter measures the tristimulus values of a color. * A spectroradiometer measures the absolute spectral radiance (intensity) or irradiance of a light source. * A spectrophotometer measures the spectral reflectance, transmittance, or relative irradiance of a color sample. * A ''spectrocolorimeter'' is a spectrophotometer that can ''calculate'' tristimulus values. * A densitometer measures the degree of light ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Proliferation
Cell proliferation is the process by which ''a cell grows and divides to produce two daughter cells''. Cell proliferation leads to an exponential increase in cell number and is therefore a rapid mechanism of tissue growth. Cell proliferation requires both cell growth and cell division to occur at the same time, such that the average size of cells remains constant in the population. Cell division can occur without cell growth, producing many progressively smaller cells (as in cleavage of the zygote), while cell growth can occur without cell division to produce a single larger cell (as in growth of neurons). Thus, cell proliferation is not synonymous with either cell growth or cell division, despite the fact that these terms are sometimes used interchangeably. Stem cells undergo cell proliferation to produce proliferating "transit amplifying" daughter cells that later differentiate to construct tissues during normal development and tissue growth, during tissue regeneration aft ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Culture Assays
A cell culture assay is any method used to assess the cytotoxicity of a material. This refers to the ''in vitro'' assessment of a material to determine whether it releases toxic chemicals in the cell. It also determines if the quantity is sufficient to kill cells, either directly or indirectly, through the inhibition of cell metabolic pathways. Cell culture evaluations are the precursor to whole animal studies and are a way to determine if significant cytotoxicity exists for the given material. Cell culture assays are standardized by ASTM, ISO, and BSI (British Standards Institution.) See also * Microphysiometry Microphysiometry is the ''in vitro'' measurement of the functions and activities of life or of living matter (as organs, tissues, or cells) and of the physical and chemical phenomena involved on a very small (micrometer) scale. The term microphysiom ... References {{DEFAULTSORT:Cell Culture Assays Biotechnology Cell biology * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MTT Assay
The MTT assay is a colorimetric assay for assessing cell metabolic activity. NAD(P)H-dependent cellular oxidoreductase enzymes may, under defined conditions, reflect the number of viable cells present. These enzymes are capable of reducing the tetrazolium dye MTT, which is chemically 3-(4,5- di methyl thiazol-2-yl)-2,5-diphenyltetrazolium bromide, to its insoluble formazan, which has a purple color. Other closely related tetrazolium dyes including XTT, MTS and the WSTs, are used in conjunction with the intermediate electron acceptor, 1-methoxy phenazine methosulfate (PMS). With WST-1, which is cell-impermeable, reduction occurs outside the cell via plasma membrane electron transport. However, this traditionally assumed explanation is currently contended as proof has also been found of MTT reduction to formazan in lipidic cellular structures without apparent involvement of oxidoreductases. Tetrazolium dye assays can also be used to measure cytotoxicity (loss of viable cells) or cy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Formazan
The formazans are compounds of the general formula -N=N-C(R')=N-NH-R" formally derivatives of formazan 2NN=CHN=NH unknown in free form. Formazan dyes are artificial chromogenic products obtained by reduction of tetrazolium salts by dehydrogenases and reductases. They have a variety of colors from dark blue to deep red to orange, depending on the original tetrazolium salt used as the substrate for the reaction. Structure and reactivity Formazans are intensely colorful compounds characterized by the following structure: N=N-C(R)=N-NH- and are closely related to azo (−N=N−) dyes. Their structure was first defined in 1892, by von Pechmann and by Bamberger and Wheelwright independently. Their deep colour and redox chemistry derive from their nitrogen-rich backbone. Formazans have a high tautomeric and conformational flexibility. Due to the two alternating double bonds in the backbone, formazans can exist in four possible isomeric forms: syn, s-cis (closed form); syn, s-tran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Probes
Molecular Probes was a biotechnology company located in Eugene, Oregon specializing in fluorescence. The company was founded in 1975 by Richard and Rosaria Haugland in their kitchen in Minnesota, then moved briefly to Texas and finally to Oregon in the early 1980s. In 1989, Molecular Probes moved from Junction City to its current location in Eugene. While in Texas, the Hauglands developed the Texas Red dye, a rhodamine derivative. Other dyes have names that reflect their Oregon heritage, including the Oregon Green and Cascade Blue dyes, while Marina Blue and the Alexa Fluor dyes are named after the Hauglands' children, Marina and Alex. Invitrogen bought Molecular Probes in 2003 for approximately $325 million in cash. The business subsequently became a part of Life Technologies, through the merger of Invitrogen and Applied Biosystems, and is now part of Thermo Fisher Scientific Thermo Fisher Scientific Inc. is an American supplier of scientific instrumentation, reagents and c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cellular Respiration
Cellular respiration is the process by which biological fuels are oxidised in the presence of an inorganic electron acceptor such as oxygen to produce large amounts of energy, to drive the bulk production of ATP. Cellular respiration may be described as a set of metabolic reactions and processes that take place in the cells of organisms to convert chemical energy from nutrients into adenosine triphosphate (ATP), and then release waste products. The reactions involved in respiration are catabolic reactions, which break large molecules into smaller ones, releasing energy. Respiration is one of the key ways a cell releases chemical energy to fuel cellular activity. The overall reaction occurs in a series of biochemical steps, some of which are redox reactions. Although cellular respiration is technically a combustion reaction, it is an unusual one because of the slow, controlled release of energy from the series of reactions. Nutrients that are commonly used by animal and plan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salt (chemistry)
In chemistry, a salt is a chemical compound consisting of an ionic assembly of positively charged cations and negatively charged anions, which results in a compound with no net electric charge. A common example is table salt, with positively charged sodium ions and negatively charged chloride ions. The component ions in a salt compound can be either inorganic, such as chloride (Cl−), or organic, such as acetate (). Each ion can be either monatomic, such as fluoride (F−), or polyatomic, such as sulfate (). Types of salt Salts can be classified in a variety of ways. Salts that produce hydroxide ions when dissolved in water are called ''alkali salts'' and salts that produce hydrogen ions when dissolved in water are called ''acid salts''. ''Neutral salts'' are those salts that are neither acidic nor basic. Zwitterions contain an anionic and a cationic centre in the same molecule, but are not considered salts. Examples of zwitterions are amino acids, many metabolites, peptid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
