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Pyranine
Pyranine is a hydrophilic, pH-sensitive fluorescent dye from the group of chemicals known as arylsulfonates. Pyranine is soluble in water and is used as a coloring agent, biological stain, optical detecting reagent, and pH indicator. Pyranine is also used in yellow highlighters to provide their characteristic fluorescence and bright yellow-green colour. It is also found in some types of soap. Synthesis Pyranine is synthesized from pyrenetetrasulfonic acid and a solution of sodium hydroxide in water under reflux. The trisodium salt crystallizes as yellow needles when adding an aqueous solution of sodium chloride. See also * Fluorescein * Fluorescence Fluorescence is one of two kinds of photoluminescence, the emission of light by a substance that has absorbed light or other electromagnetic radiation. When exposed to ultraviolet radiation, many substances will glow (fluoresce) with colore ... References {{reflist External links CTD's Pyranine pagefrom the Compa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrophilic
A hydrophile is a molecule or other molecular entity that is attracted to water molecules and tends to be dissolved by water.Liddell, H.G. & Scott, R. (1940). ''A Greek-English Lexicon'' Oxford: Clarendon Press. In contrast, hydrophobes are not attracted to water and may seem to be repelled by it. Hygroscopics ''are'' attracted to water, but are not dissolved by water. Molecules A hydrophilic molecule or portion of a molecule is one whose interactions with water and other polar substances are more thermodynamically favorable than their interactions with oil or other hydrophobic solvents. They are typically charge-polarized and capable of hydrogen bonding. This makes these molecules soluble not only in water but also in polar solvents. Hydrophilic molecules (and portions of molecules) can be contrasted with hydrophobic molecules (and portions of molecules). In some cases, both hydrophilic and hydrophobic properties occur in a single molecule. An example of these amphiphilic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluorescent Dye
A fluorophore (or fluorochrome, similarly to a chromophore) is a fluorescence, fluorescent chemical compound that can re-emit light upon light excitation. Fluorophores typically contain several combined aromaticity, aromatic groups, or planar or cyclic molecules with several pi bond, π bonds. Fluorophores are sometimes used alone, as a dye tracing, tracer in fluids, as a dye for staining of certain structures, as a substrate of enzymes, or as a probe or indicator (when its fluorescence is affected by environmental aspects such as polarity or ions). More generally they are covalent bond, covalently bonded to macromolecules, serving as a markers (or dyes, or tags, or reporters) for affine or bioactive reagents (antibodies, peptides, nucleic acids). Fluorophores are notably used to stain tissues, cells, or materials in a variety of analytical methods, such as Fluorescence microscope, fluorescent imaging and fluorescence spectroscopy, spectroscopy. Fluorescein, via its amine-react ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PH Indicator
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] |
Highlighter
A highlighter, also called a fluorescent pen, is a type of writing device used to bring attention to sections of text by marking them with a vivid, translucent colour. A typical highlighter is fluorescent yellow, with the colour coming from pyranine. Different compounds, such as rhodamines ( Rhodamine 6GD, Rhodamine B) are used for other colours. History A highlighter is a felt-tip marker filled with transparent fluorescent ink instead of black or opaque ink. The first highlighter was invented by Dr. Frank Honn in 1962 and produced by Carter's Ink Company, using the trademarked name Hi-Liter. Avery Dennison Corporation now owns the brand, having acquired Carter's in 1975. Styles Many highlighters come in bright, often fluorescent and vibrant colours. Being fluorescent, highlighter ink glows under black light. The most common colour for highlighters is yellow, but they are also found in orange, red, pink, purple, blue, and green varieties. Some yellow highlighters may l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluorescence
Fluorescence is one of two kinds of photoluminescence, the emission of light by a substance that has absorbed light or other electromagnetic radiation. When exposed to ultraviolet radiation, many substances will glow (fluoresce) with colored visible light. The color of the light emitted depends on the chemical composition of the substance. Fluorescent materials generally cease to glow nearly immediately when the radiation source stops. This distinguishes them from the other type of light emission, phosphorescence. Phosphorescent materials continue to emit light for some time after the radiation stops. This difference in duration is a result of quantum spin effects. Fluorescence occurs when a photon from incoming radiation is absorbed by a molecule, exciting it to a higher energy level, followed by the emission of light as the molecule returns to a lower energy state. The emitted light may have a longer wavelength and, therefore, a lower photon energy than the absorbed radi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soap
Soap is a salt (chemistry), salt of a fatty acid (sometimes other carboxylic acids) used for cleaning and lubricating products as well as other applications. In a domestic setting, soaps, specifically "toilet soaps", are surfactants usually used for washing, bathing, and other types of housekeeping. In industrial settings, soaps are used as thickeners, components of some lubricants, emulsifiers, and catalysts. Soaps are often produced by mixing fats and oils with a Base (chemistry), base. Humans have used soap for millennia; evidence exists for the production of soap-like materials in ancient Babylon around 2800 BC. Types Toilet soaps In a domestic setting, "soap" usually refers to what is technically called a toilet soap, used for household and personal cleaning. Toilet soaps are salts of fatty acids with the general formula (Carboxylate ion, RCO2−)M+, where M is Sodium, Na (sodium) or Potassium, K (potassium). When used for cleaning, soap solubilizes particles and g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Chloride
Sodium chloride , commonly known as Salt#Edible salt, edible salt, is an ionic compound with the chemical formula NaCl, representing a 1:1 ratio of sodium and chloride ions. It is transparent or translucent, brittle, hygroscopic, and occurs as the mineral halite. In its edible form, it is commonly used as a condiment and curing (food preservation), food preservative. Large quantities of sodium chloride are used in many industrial processes, and it is a major source of sodium and chlorine compounds used as feedstocks for further Chemical synthesis, chemical syntheses. Another major application of sodium chloride is deicing of roadways in sub-freezing weather. Uses In addition to the many familiar domestic uses of salt, more dominant applications of the approximately 250 million tonnes per year production (2008 data) include chemicals and de-icing.Westphal, Gisbert ''et al.'' (2002) "Sodium Chloride" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim . Chem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluorescein
Fluorescein is an organic compound and dye based on the xanthene tricyclic structural motif, formally belonging to Triarylmethane dye, triarylmethine dyes family. It is available as a dark orange/red powder slightly soluble in water and alcohol. It is used as a fluorescent Flow tracer, tracer in many applications. The color of its aqueous solutions is green by reflection and orange by transmission (its spectral properties are dependent on pH of the solution), as can be noticed in spirit level, bubble levels, for example, in which fluorescein is added as a colorant to the Alcohol (chemistry), alcohol filling the tube in order to increase the visibility of the air bubble contained within. More concentrated solutions of fluorescein can even appear red (because under these conditions nearly all incident emission is re-absorbed by the solution). It is on the WHO Model List of Essential Medicines, World Health Organization's List of Essential Medicines. Uses Fluorescein sodium, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluorescence
Fluorescence is one of two kinds of photoluminescence, the emission of light by a substance that has absorbed light or other electromagnetic radiation. When exposed to ultraviolet radiation, many substances will glow (fluoresce) with colored visible light. The color of the light emitted depends on the chemical composition of the substance. Fluorescent materials generally cease to glow nearly immediately when the radiation source stops. This distinguishes them from the other type of light emission, phosphorescence. Phosphorescent materials continue to emit light for some time after the radiation stops. This difference in duration is a result of quantum spin effects. Fluorescence occurs when a photon from incoming radiation is absorbed by a molecule, exciting it to a higher energy level, followed by the emission of light as the molecule returns to a lower energy state. The emitted light may have a longer wavelength and, therefore, a lower photon energy than the absorbed radi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Comparative Toxicogenomics Database
The Comparative Toxicogenomics Database (CTD) is a public website and research tool launched in November 2004 that curates scientific data describing relationships between chemicals/drugs, genes/proteins, diseases, taxa, phenotypes, GO annotations, pathways, and interaction modules. The database is maintained by the Department of Biological Sciences at North Carolina State University. Background The Comparative Toxicogenomics Database (CTD) is a public website and research tool that curates scientific data describing relationships between chemicals, genes/proteins, diseases, taxa, phenotypes, GO annotations, pathways, and interaction modules, launched on November 12, 2004. The database is maintained by the Department of Biological Sciences at North Carolina State University. Goals and objectives One of the primary goals of CTD is to advance the understanding of the effects of environmental chemicals on human health on the genetic level, a field called toxicogenomics. The etiolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Staining Dyes
Staining is a technique used to enhance contrast in samples, generally at the microscopic level. Stains and dyes are frequently used in histology (microscopic study of biological tissues), in cytology (microscopic study of cells), and in the medical fields of histopathology, hematology, and cytopathology that focus on the study and diagnoses of diseases at the microscopic level. Stains may be used to define biological tissues (highlighting, for example, muscle fibers or connective tissue), cell populations (classifying different blood cells), or organelles within individual cells. In biochemistry, it involves adding a class-specific (DNA, proteins, lipids, carbohydrates) dye to a substrate to qualify or quantify the presence of a specific compound. Staining and fluorescent tagging can serve similar purposes. Biological staining is also used to mark cells in flow cytometry, and to flag proteins or nucleic acids in gel electrophoresis. Light microscopes are used for viewing s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluorescent Dyes
A fluorophore (or fluorochrome, similarly to a chromophore) is a fluorescent chemical compound that can re-emit light upon light excitation. Fluorophores typically contain several combined aromatic groups, or planar or cyclic molecules with several π bonds. Fluorophores are sometimes used alone, as a tracer in fluids, as a dye for staining of certain structures, as a substrate of enzymes, or as a probe or indicator (when its fluorescence is affected by environmental aspects such as polarity or ions). More generally they are covalently bonded to macromolecules, serving as a markers (or dyes, or tags, or reporters) for affine or bioactive reagents (antibodies, peptides, nucleic acids). Fluorophores are notably used to stain tissues, cells, or materials in a variety of analytical methods, such as fluorescent imaging and spectroscopy. Fluorescein, via its amine-reactive isothiocyanate derivative fluorescein isothiocyanate (FITC), has been one of the most popular fluorophores. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
