379 Resultater for: "VARLP080520VARI00001"

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Fluorescein isothiocyanate (FITC) is yellow-orange in color with an absorption maximum at 495nm. Upon excitation, it emits a yellow-green color with an emission maximum at 525 nm. It is widely used to attach a fluorescent label to proteins via the amine group. The isothiocyanate group reacts with amino terminal and primary amines in proteins. It has been used for the labeling of proteins including antibodies and lectins. Fluorescein isothiocyanate isomer I has been proposed as a contact sensitiser.

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Safranin O, also known as basic red 2, is a basic, cationic, and metachromatic azine dye used as a biological stain. The characteristic azine chromophore contains the phenazine, a planar, tricyclic dibenzopyrazine, which consists of two non-planar benzene rings linked by two nitrogen atoms. A delocalised positive charge, an alternation of aromatic and quinonoid structures, and diazotisable amine groups constitute the chromophoric system. c-Methylation makes this dye of moderate overall size. The trimethyl cationic form of safranine is lipophilic, whereas the dimethyl forms are weakly hydrophilic. The dye is commercially available as a chloride.

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JB-4 is a water-soluble, GMA based, plastic resin kit intended for use in the preparation of embedded samples for high resolution light microscopy. It is a technique now widely used for research and clinical diagnosis. JB-4 yields semi-thin sections (0.5μ-2μ) with excellent morphological preservation.

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Tetrazolium blue chloride (BTC) is a colorless tetrazolium compound that upon reduction forms a colored diformazan. The reactivity has been applied to the analysis of reducing compounds including the nanomolar detection of reducing sugars and carbidopa and methyldopa. BTC has been used for histological staining of mouse coronal brain sections and rat brain sections. In combination with 4-nitrocatechol, tetrazolium blue chloride forms a ternary complex with molybdenum(VI) for extraction and spectrophotometric determination of molybdenum. It has also been used to stain Francisella tularensis cells for tularemic microagglutination test.

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Thiazolyl Blue Tetrazolium Blue (MTT) may be used in measurement of cell proliferation. MTT produces a yellowish solution that is converted to dark blue, water-insoluble MTT formazan by mitochondrial dehydrogenases of living cells. The blue crystals are solubilized with acidified isopropanol and the intensity is measured colorimetrically at 570 nm. MTT has been used as a histochemical/cytochemical reagent and for the detection of NAD. ADP-linked enzyme systems in tissue cannot be detected with MTT, due to binding of the cation by the cyanide trap used. MTT is rapidly reduced to the formazan, which chelates with nickel, copper, and cobalt; the cobalt chelate has been used in oxidative systems.

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Naphthol blue black (NBB) is an textile diazo dye, with high photo- and thermal-stability. Photoelectrochemical degradation of this dye yields colorless quinone as end product. Pure grade of NBB is generally used for dyeing foodstuffs, drugs and cosmetics. It is also used as a protein stain in chromatography and electrophoresis and as a biological stain. Commercial grade of NBB is a widely used textile dye. It is used in dyeing wool, nylon, silk and in textile printing. In addition, it is also employed for colouring of soaps, anodised aluminum and casein, wood stains and writing ink preparation.

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Acridine orange is a metachromatic dye which can stain DNA, RNA and acid glycosaminoglycans. At low concentrations, it intercalates into DNA and precipitates RNA. However, at high concentrations it denatures and precipitates both RNA and DNA. Acridine orange is also used to analyse autophagy. It enters into acidic organelles in a pH-dependent manner. At neutral pH, acridine orange gives a green fluorescence and in acidic conditions, it accumulates in acidic organelles giving a bright red fluorescence.

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N,N-Dimethyl-p-phenylenediamine dihydrochloride (DMPD) has been used in the HID-AB (high iron diamine-alcian blue) staining of intestinal tract samples. N,N-Dimethyl-p-phenylenediamine dihydrochloride (DMPD) is used for the determination of peroxidase. DMPD is converted into a red pigment of semiquinone nature. It is also used in the HID-AB (high iron diamine-alcian blue) staining procedures, which are used to differentiate between sialomucin and sulfomucin in the gastrointestinal tract.

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Acriflavine also interacts with HIF-1α (hypoxia-inducible factor 1 α) and HIF-2α, and thereby suppresses dimer formation of HIF-1 and transcriptional function. It also has negative effect on tumor growth and vascularization. Acriflavine also exhibits trypanocidal, antibacterial and antiviral activities.

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Reagent for aluminium. Aurintricarboxylic acid readily polymerises in aqueous solution, forming a stable free radical that inhibits protein-nucleic acid interactions. It is a potent inhibitor of ribonuclease and topoisomerase II by preventing the binding of the nucleic acid to the enzyme. It stimulates tyrosine phosphorylation processes including the Jak2/STAT5 pathway in NB2 lymphoma cells, ErbB4 in neuroblastoma cells, and MAP kinases, Shc proteins, phosphatidylinositide 3-kinase and phospholipase C in PC12 cells. Aurintricarboxylic acid inhibits apoptosis in many cell types. Its neuroprotective effect, perhaps due to its ability to prevent down-regulation of Ca²⁺ impermeable GluR2 receptors or to its ability to inhibit calpain, a Ca²⁺-activated protease that is activated during apoptosis.

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This is a mounting medium (contains 45% acrylic resin and 55% xylenes) used in microscopy. It is an adhesive and specimen preservative that can be used manually and in automated coverslipping equipment. Special purpose adhesive and sealant for use with glass, non plastic and other non-reactive materials.

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Spurr resin is a hydrophobic resin. It is less viscous than epon mixtures and is easier to dispense. The low viscosity of the resin contributes to its penetration in tissue, mineral and dense structures. A low viscosity of 60 cps also allows easy penetration into a variety of difficult materials.

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Bromocresol Green (BCG), also known as bromcresol green, is a synthetic, anionic, triphenylmethane dye belonging to the phthalein and sulphonphthalein dyes group. It is commonly used as a pH indicator as it changes colour from yellow to blue-green at pH 3,8 to 5,4. The monosodium salt of bromocresol green is highly ionisable in water. The dye at a higher pH level produces a large and weakly lipophilic dianion.

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Light green SF yellowish (LGSFY) is a disodium salt of an acid triphenylmethane dye. It is also known as Light Green, Lissamine Green SF, Food Green 2, Green No. 205, Acid Green, Acid Brilliant Green 5, and Acid Brilliant Green SF. LGSFY is an important component of Papanicolaou stains in addition to eosin Y and bismark brown Y. Light green SF yellowish is a histological stain for collagen and a permitted colorant for foodstuffs and beverages.

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Brilliant Blue R (C.l. 42660) is a triaminotriarylmethane dye with two amino groups being benzylated and one phenylated. It is also known as brilliant indocyanine 6B and coomassie blue R250. Brilliant Blue R has been widely used for protein band detection after SDS-PAGE (sodium dodecyl sulfate-polyacrylamide gel electrophoresis).

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Spin trap used in conjunction with Fe²⁺ to detect NO in brain, kidney, liver, and other tissues. Simultaneous direct measurement of NO* and pO₂ has been reported. A copper chelator, it has been used to quantitate copper in biological materials by ESR and is an inhibitor of superoxide dismutase, ascorbate oxidase, and other enzymes. Also used for colorimetric determination of small quantities of arsenic. Silver diethyldithiocarbamate has been used in cell culture. Also used for colorimetric determination of small quantities of arsenic. Spin trap used in conjunction with Fe²⁺ to detect NO in brain, kidney, liver, and other tissues. Simultaneous direct measurement of NO* and pO₂ has been reported. A copper chelator, it has been used to quantitate copper in biological materials by ESR and is an inhibitor of superoxide dismutase, ascorbate oxidase, and other enzymes.

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Acridine orange hemi (zinc chloride) salt has been used to stain primary human umbilical vein endothelial cells (HUVEC) and is used in micronucleus tests (MNTs). Acridine orange, a cell-permeable metachromatic fluorescent cationic dye that intercalates DNA and RNA, is used in fluorescence and epiflouresence microscopy. Acridine orange dye has been used to analyse mitochondria and lysosomal content by flow cytometry, characterise multidrug resistance, and measure changes in mitochondrial mass during apoptosis in rat thymocytes.

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Folin & Ciocalteu's phenol reagent is most commonly used in the Lowry method for determining protein concentration. It has also been used for the quantification of total phenolics. In this method, protein is pretreated with copper(II) in a modified biuret reagent (alkaline copper solution
stabilized with sodium potassium tartrate). Addition of the phenol reagent generates chromogens that give increasing absorbance between 550-750nm. Normally, absorbance at the peak (750 nm) or shoulder (660 nm) are used to quantitate protein concentrations between 1 - 100 mg/ml while absorbance at 550 nm is used to quantitate higher protein concentrations.

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Certified for Giemsa stain for blood films and for the Wolbach′s Giemsa method for paraffin sections. Giemsa is a versatile polychromatic stain, which is suitable for staining a diverse range of specimens. It is a buffered thiazine-eosinate solution designed to provide coloration of blood cells. Giemsa’s stain is frequently used for diagnostic purposes in hematology to differentiate the nuclear and cytoplasmic morphology of platelets, RBCs, WBCs, and parasites. It is frequently used in combination with other dye solutions as May-Grunwald’s solution for Pappenheim (MGG) and Wright-Giemsa. The Giemsa stain was adapted to histology due to its unique staining of chromatin, nuclear membranes, and cytoplasmic elements. Giemsa′s staining solution is composed of methylene blue, azure, and eosin.