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SYBR Safe
SYBR Safe is a cyanine dye used as a nucleic acid stain in molecular biology. SYBR Safe is one of a number of SYBR dyes made by the Life Technologies Corporation. SYBR Safe binds to DNA. The resulting DNA-dye-complex absorbs blue light (λmax = 509 nm) and emits green light (λmax = 524 nm). Safety SYBR Safe is marketed as a safer alternative to ethidium bromide. However, as the molecule itself is quite a bit larger than ethidium bromide, it does not bind to the column of a gel extraction as easily, making it less efficient when trying to clone a DNA fragment into a plasmid. SYBR Safe has a very similar structure to thiazole orange, which has a methyl group attached to the charged nitrogen, whereas SYBR Safe has an ''N''-propyl group. Thiazole Orange has been shown to be three to four times less mutagenic than ethidium bromide whereas SYBR Safe is four to five times less mutagenic. Additionally, according to the Life Technologies website, SYBR Safe is not lethal in ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dimethylsulfoxide
Dimethyl sulfoxide (DMSO) is an organosulfur compound with the formula ( CH3)2. This colorless liquid is the sulfoxide most widely used commercially. It is an important polar aprotic solvent that dissolves both polar and nonpolar compounds and is miscible in a wide range of organic solvents as well as water. It has a relatively high boiling point. DMSO has the unusual property that many individuals perceive a garlic-like taste in the mouth after DMSO makes contact with their skin. In terms of chemical structure, the molecule has idealized Cs symmetry. It has a trigonal pyramidal molecular geometry consistent with other three-coordinate S(IV) compounds, with a nonbonded electron pair on the approximately tetrahedral sulfur atom. Synthesis and production Dimethyl sulfoxide was first synthesized in 1866 by the Russian scientist Alexander Zaytsev, who reported his findings in 1867. Dimethyl sulfoxide is produced industrially from dimethyl sulfide, a by-product of the Kraft ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyanine Dye
Cyanines, also referred to as tetramethylindo(di)-carbocyanines are a synthetic dye family belonging to the polymethine group. Although the name derives etymologically from terms for shades of blue, the cyanine family covers the electromagnetic spectrum from near IR to UV. Chemically, cyanines are a conjugated system between two nitrogen atoms; in each resonance structure, exactly one nitrogen atom is oxidized to an iminium. Typically, they form part of a nitrogenous heterocyclic system. The main application for cyanine dyes is in biological labeling. Nevertheless, there is a wide literature on both their synthesis and uses, and cyanines are common in some CD and DVD media. Structure Cyanines have been classified in many ways: * ''Streptocyanines'' or ''open chain cyanines'': : R2N+=CH H=CH'n''-NR2 (I) * ''Hemicyanines'': : Aryl=N+=CH H=CH'n''-NR2 (II) * ''Closed chain cyanines'': :Aryl=N+=CH H=CH'n''-N=Aryl (III) Additionally, these classes are recognized: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleic Acid
Nucleic acids are biopolymers, macromolecules, essential to all known forms of life. They are composed of nucleotides, which are the monomers made of three components: a 5-carbon sugar, a phosphate group and a nitrogenous base. The two main classes of nucleic acids are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). If the sugar is ribose, the polymer is RNA; if the sugar is the ribose derivative deoxyribose, the polymer is DNA. Nucleic acids are naturally occurring chemical compounds that serve as the primary information-carrying molecules in cells and make up the genetic material. Nucleic acids are found in abundance in all living things, where they create, encode, and then store information of every living cell of every life-form on Earth. In turn, they function to transmit and express that information inside and outside the cell nucleus to the interior operations of the cell and ultimately to the next generation of each living organism. The encoded information is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Staining
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 viewin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Biology
Molecular biology is the branch of biology that seeks to understand the molecular basis of biological activity in and between cells, including biomolecular synthesis, modification, mechanisms, and interactions. The study of chemical and physical structure of biological macromolecules is known as molecular biology. Molecular biology was first described as an approach focused on the underpinnings of biological phenomena - uncovering the structures of biological molecules as well as their interactions, and how these interactions explain observations of classical biology. In 1945 the term molecular biology was used by physicist William Astbury. In 1953 Francis Crick, James Watson, Rosalind Franklin, and colleagues, working at Medical Research Council unit, Cavendish laboratory, Cambridge (now the MRC Laboratory of Molecular Biology), made a double helix model of DNA which changed the entire research scenario. They proposed the DNA structure based on previous research done by Ro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agarose Gel Electrophoresis
Agarose gel electrophoresis is a method of gel electrophoresis used in biochemistry, molecular biology, genetics, and clinical chemistry to separate a mixed population of macromolecules such as DNA or proteins in a matrix of agarose, one of the two main components of agar. The proteins may be separated by charge and/or size (isoelectric focusing agarose electrophoresis is essentially size independent), and the DNA and RNA fragments by length. Biomolecules are separated by applying an electric field to move the charged molecules through an agarose matrix, and the biomolecules are separated by size in the agarose gel matrix. Agarose gel is easy to cast, has relatively fewer charged groups, and is particularly suitable for separating DNA of size range most often encountered in laboratories, which accounts for the popularity of its use. The separated DNA may be viewed with stain, most commonly under UV light, and the DNA fragments can be extracted from the gel with relative ease. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethidium Bromide
Ethidium bromide (or homidium bromide, chloride salt homidium chloride) is an intercalating agent commonly used as a fluorescent tag (nucleic acid stain) in molecular biology laboratories for techniques such as agarose gel electrophoresis. It is commonly abbreviated as EtBr, which is also an abbreviation for bromoethane. To avoid confusion, some laboratories have used the abbreviation EthBr for this salt. When exposed to ultraviolet light, it will fluoresce with an orange colour, intensifying almost 20-fold after binding to DNA. Under the name homidium, it has been commonly used since the 1950s in veterinary medicine to treat trypanosomiasis in cattle. The high incidence of antimicrobial resistance makes this treatment impractical in some areas, where the related isometamidium chloride is used instead. Despite its reputation as a mutagen, it is relatively safe to handle. Structure, chemistry, and fluorescence As with most fluorescent compounds, ethidium bromide is aromatic. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SYBR Green I
SYBR Green I (SG) is an asymmetrical cyanine dye used as a nucleic acid stain in molecular biology. The SYBR family of dyes is produced by Molecular Probes Inc., now owned by Thermo Fisher Scientific. SYBR Green I binds to DNA. The resulting DNA-dye-complex best absorbs 497 nanometer blue light (λmax = 497 nm) and emits green light (λmax = 520 nm). The stain preferentially binds to double-stranded DNA, but will stain single-stranded (ss) DNA with lower performance. SYBR Green can also stain RNA with a lower performance than ssDNA. Uses SYBR Green finds usage in several areas of biochemistry and molecular biology. It is used as a dye for the quantification of double stranded DNA in some methods of quantitative PCR. It is also used to visualise DNA in gel electrophoresis. Higher concentrations of SYBR Green can be used to stain agarose gels in order to visualise the DNA present. In addition to labelling pure nucleic acids, SYBR Green can also be used for labelling o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SYBR Gold
SYBR Gold is an asymmetrical cyanine dye. It can be used as a stain for double-stranded DNA, single-stranded DNA, and RNA. SYBR Gold is the most sensitive fluorescent stain of the SYBR family of dyes for the detection of nucleic acids. The SYBR family of dyes is produced by Molecular Probes Inc., now owned by Thermo Fisher Scientific SYBR Gold is more sensitive than ethidium bromide, SYBR Green I, and SYBR Green II for detecting various types of nucleic acids. SYBR Gold's superior sensitivity is due to the high fluorescence quantum yield of the dye-nucleic acid complexes (~0.6-0.7) and the dye's large fluorescence enhancement upon binding to nucleic acids (~1000-fold). SYBR Gold can detect as little as 25 pg of DNA which makes it >10-fold more sensitive than ethidium bromide for detecting nucleic acids in denaturing urea, gyoxal, and formaldehyde gels, even with 300 nm transillumination. Fluorescence properties SYBR Gold has two fluorescence excitation maxima when bound ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GelGreen
GelGreen is an intercalating nucleic acid stain used in molecular genetics for agarose gel DNA electrophoresis. GelGreen consists of two acridine orange subunits that are bridged by a linear oxygenated spacer. Its fluorophore, and therefore its optical properties, are essentially identical to those of other ''N''-alkylacridinium orange dyes. When exposed to ultraviolet light, it will fluoresce with a greenish color that strongly intensifies after binding to DNA. The substance is marketed as a less toxic and more sensitive alternative to ethidium bromide. GelGreen is sold as a solution in either DMSO or water. {{short description, DNA gel stain for molecular genetics See also * Ethidium bromide * GelRed * SYBR Green I * Agarose gel electrophoresis and gel electrophoresis of nucleic acids * Acridine orange Acridine orange is an organic compound that serves as a nucleic acid-selective fluorescent dye with cationic properties useful for cell cycle determination. Acridine oran ... [...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 st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyanine Dyes
Cyanines, also referred to as tetramethylindo(di)-carbocyanines are a synthetic dye family belonging to the polymethine group. Although the name derives etymologically from terms for shades of blue, the cyanine family covers the electromagnetic spectrum from near IR to UV. Chemically, cyanines are a conjugated system between two nitrogen atoms; in each resonance structure, exactly one nitrogen atom is oxidized to an iminium. Typically, they form part of a nitrogenous heterocyclic system. The main application for cyanine dyes is in biological labeling. Nevertheless, there is a wide literature on both their synthesis and uses, and cyanines are common in some CD and DVD media. Structure Cyanines have been classified in many ways: * ''Streptocyanines'' or ''open chain cyanines'': : R2N+=CH H=CH'n''-NR2 (I) * ''Hemicyanines'': : Aryl=N+=CH H=CH'n''-NR2 (II) * ''Closed chain cyanines'': :Aryl=N+=CH H=CH'n''-N=Aryl (III) Additionally, these classes are recognized: * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
