Difference between revisions of "Methylene blue" - New World Encyclopedia
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| − | '''Methylene blue''' | + | '''Methylene blue''' (or MB) is a basic aniline dye with the [[empirical formula]]: [[carbon|C]]<sub>16</sub>[[hydrogen|H]]<sub>18</sub>[[chlorine|Cl]][[nitrogen|N]]<sub>3</sub>[[sulfur|S]]. Its anhydrous molecular formula is [[carbon|C]]<sub>16</sub>[[hydrogen|H]]<sub>18</sub>[[hydrogen|H]]<sub>3</sub>[[sulfur|S]][[chlorine|Cl]], and has many uses in a range of different fields, including [[biology]], [[chemistry]], medicine, as well as aquaculture. At room temperature, it appears as a solid, odorless, dark green powder, that yields a blue solution when dissolved in [[water]]. |
==Other Names== | ==Other Names== | ||
| − | Trade names for methylene blue include Desmoid piller, Desmoidpillen, Panatone, Urolene Blue, and Vitableu | + | Trade names for methylene blue include Desmoid piller, Desmoidpillen, Panatone, Urolene Blue, and Vitableu. Its synonyms include Phenothiazine-5-ium, 3,7-bis(dimethylamino)-, chloride (9CI); C.I. Basic Blue 9 (8CI); methylthionine chloride; methylthioninium chloride; tetramethylthionine chloride; swiss blue; aizen methylene blue; C.I. 52015. Methylene blue should not be confused with methyl blue, another histology stain, new methylene blue, nor with the methyl violets often used as [[pH indicator]]s. |
==Uses== | ==Uses== | ||
===Chemistry=== | ===Chemistry=== | ||
| − | Methylene blue is widely used a [[redox]] indicator in [[analytical chemistry]] meaning that it indicates the presence or absence of [[oxygen]]. [[Oxygen]]-rich environments are said to be oxidizing. Oxidizing chemicals, such as oxygen and chlorine, strip electrons away from atoms of other elements. Chemical elements that have such a strong attraction for electrons that they can take [[electron]]s away from other types of atoms are known as oxidizing agents, and are very useful in chemistry. Methylene blue indicates the presence of oxidizing agents because it is oxidized | + | Methylene blue is widely used a [[redox]] indicator in [[analytical chemistry]] meaning that it indicates the presence or absence of [[oxygen]]. [[Oxygen]]-rich environments are said to be oxidizing. Oxidizing chemicals, such as oxygen and chlorine, strip electrons away from atoms of other elements. Chemical elements that have such a strong attraction for electrons that they can take [[electron]]s away from other types of atoms are known as oxidizing agents, and are very useful in chemistry. Methylene blue indicates the presence of oxidizing agents because it is itself oxidized by these compounds. When [[electron]]s are stripped from methylene blue, the resulting molecule imparts a blue color to the solution—giving a clear sign of a chemical change.<ref>[http://www.americanchemistry.com/s_chlorine/sec_content.asp?CID=1251&DID=4729&CTYPEID=113 Methylene Blue, Part 2: The Chemist's Indicator] ''American Chemistry Council.'' December 2006. Retrieved July 20, 2007.</ref> |
| + | |||
| + | The redox properties can be seen in a classical demonstration of chemical kinetics in general chemistry, the "blue bottle" experiment. Typically, a solution is made of [[glucose]], methylene blue, and [[sodium hydroxide]]. Upon shaking the bottle, the oxygen in solution oxidizes methylene blue, and the solution turns blue. The glucose will gradually reduce the methylene blue to its colorless (reduced) form. Hence, when the dissolved oxygen is entirely consumed, the solution will turn colorless.<ref>[http://www.cci.ethz.ch/experiments/methylen/en/stat.html Redox behavior of methylene blue (blue bottle)] ''Swiss Federal Institute of Technology Zurich'' Feb 12, 2007. Retrieved July 20, 2007.</ref> Methylene blue is also used to make the reaction between Fehling's solution and reducing sugars more visible, and as a reagent in [[redox]] [[titration]]s in volumetric analysis.<ref>[http://www.starch.dk/isi/methods/27DE.htm ISI 27-1e Determination of Reducing Power and DE by Lane and Eynon's method.] ''International Starch Institute'' May 1999. Retrieved July 20, 2007.</ref> | ||
===Biology=== | ===Biology=== | ||
| − | Methylene blue is commonly used by biologists as a dye that assists in the identification of [[bacteria]]. Because [[bacteria]] are practically colorless, adding a drop or two of methylene blue to a [[microscope]] slide enables the biologists to see bacterial shapes and structures. Dyes like methylene blue (referred to as stains in [[biology]]) work by binding to biological [[tissue]]s as a result of chemical attractions. Methylene blue is at its deepest shade of blue when in contact with [[acid]]s, which makes it very useful in the identification of [[nucleic acid]]s, like DNA and RNA.<ref>[http://www.americanchemistry.com/s_chlorine/sec_content.asp?CID=1252&DID=4730&CTYPEID=113 Methylene Blue, Part 1: The Biologist's Dye] ''American Chemistry Council'' November 2006. Retrieved July 20, 2007.</ref> It can also work as an alternative to the chemical crystal violet in [[Bacteria|cellular structure|gram's staining procedures]]. <ref>Wang, Nam Sun [http://www.eng.umd.edu/~nsw/ench485/lab9b.htm Experiment Number 9B | + | Methylene blue is commonly used by biologists as a dye that assists in the identification of [[bacteria]]. Because [[bacteria]] are practically colorless, adding a drop or two of methylene blue to a [[microscope]] slide enables the biologists to see bacterial shapes and structures. Dyes like methylene blue (referred to as stains in [[biology]]) work by binding to biological [[tissue]]s as a result of chemical attractions. Methylene blue is at its deepest shade of blue when in contact with [[acid]]s, which makes it very useful in the identification of [[nucleic acid]]s, like DNA and RNA.<ref>[http://www.americanchemistry.com/s_chlorine/sec_content.asp?CID=1252&DID=4730&CTYPEID=113 Methylene Blue, Part 1: The Biologist's Dye] ''American Chemistry Council'' November 2006. Retrieved July 20, 2007.</ref> It can also work as an alternative to the chemical crystal violet in [[Bacteria|cellular structure|gram's staining procedures]].<ref>Wang, Nam Sun [http://www.eng.umd.edu/~nsw/ench485/lab9b.htm Experiment Number 9B |
CELL DIFFERENTIATION BY GRAM'S STAIN] ''Department of Chemical & Biomolecular Engineering | CELL DIFFERENTIATION BY GRAM'S STAIN] ''Department of Chemical & Biomolecular Engineering | ||
| − | University of Maryland'' Retrieved July 20, 2007.</ref> | + | University of Maryland'' Retrieved July 20, 2007.</ref> |
| + | |||
| + | Given this attraction to [[nucleic acid]]s, methylene blue has also been used in procedures such as northern blotting/ northern hybridization (which is used for the detection of specific RNA sequences), in order to visualize RNA.<ref>http://wheat.pw.usda.gov/~lazo/methods/iubio/northgel.html. Retrieved July 20, 2007.</ref> In addition, methylene blue is used as a safer alternative for another [[chemical]] called ethidium bromide (normally used in the visualization of DNA on gels in blotting procedures [[Antibody|western blot]]. This is because ethidium bromide is a potent [[carcinogen]] and mutagen, and also because the short-length UV [[light]] that is required for ethidium bromide to fluoresce (and thereby aid in visualizing the DNA) can cause unwanted mutations in the DNA sample itself. Drawbacks of using methylene blue as a replacement are that it is less sensitive than ethidium bromide, and also fades rapidly after staining. This makes methylene blue an unideal replacement (though suitable for school contexts, due to it's less harmful nature). <ref>Madden, Dean. [http://www.bioscience-explained.org/EN1.2/schollar.html Safer Stains for DNA] ''Bioscience explained 1.2'' Retrieved July 20, 2007.</ref> | ||
Methylene blue has also been used as a way to obtain a quick estimate of the percentage of viable [[cell]]s in a [[yeast]] sample, since viable yeast cells contain an [[enzyme]] that decolorizes methylene blue, whereas dead cells do not. As a result, when cells from a [[yeast]] are suspended in the dye, it penetrates all the cells, and leaves the dead cells blue, and the living cells unstained. Despite this, it must be noted that this method simply indicates whether an [[enzyme]] is present in the [[yeast]] [[cell]]s (not whether the cells are incapable of dividing), and therefore is less accurate than other methods, and should be used to simply provide a rapid estimate. <ref>Painting, K and Kirsophttp, B. [http://www.wfcc.info/tis/info2.html A QUICK METHOD FOR ESTIMATING THE PERCENTAGE OF VIABLE CELLS IN A YEAST POPULATION, USING METHYLENE BLUE STAINING] ''National Collection of Yeast Cultures, AFRC Institute of Food Research'' 1989. Retrieved July 20, 2007.</ref> | Methylene blue has also been used as a way to obtain a quick estimate of the percentage of viable [[cell]]s in a [[yeast]] sample, since viable yeast cells contain an [[enzyme]] that decolorizes methylene blue, whereas dead cells do not. As a result, when cells from a [[yeast]] are suspended in the dye, it penetrates all the cells, and leaves the dead cells blue, and the living cells unstained. Despite this, it must be noted that this method simply indicates whether an [[enzyme]] is present in the [[yeast]] [[cell]]s (not whether the cells are incapable of dividing), and therefore is less accurate than other methods, and should be used to simply provide a rapid estimate. <ref>Painting, K and Kirsophttp, B. [http://www.wfcc.info/tis/info2.html A QUICK METHOD FOR ESTIMATING THE PERCENTAGE OF VIABLE CELLS IN A YEAST POPULATION, USING METHYLENE BLUE STAINING] ''National Collection of Yeast Cultures, AFRC Institute of Food Research'' 1989. Retrieved July 20, 2007.</ref> | ||
Revision as of 17:17, 20 July 2007
| Methylene blue | |
|---|---|
 
| |
| Chemical name | 3,7-bis(Dimethylamino)- phenothiazin-5-ium chloride or Tetramethyl thionine |
| Empirical formula | C16H18ClN3S |
| Molecular mass | 319.86 g/mol |
| CAS number | [61-73-4] |
| EC number | 200-515-2 |
| Melting point | 100 °C |
| Boiling point | Decomposes |
| SMILES[1] | CN(C)c3ccc2nc1ccc(N(C) C)cc1[s+]c2c3.[Cl-] |
| Disclaimer and references | |
Methylene blue (or MB) is a basic aniline dye with the empirical formula: C16H18ClN3S. Its anhydrous molecular formula is C16H18H3SCl, and has many uses in a range of different fields, including biology, chemistry, medicine, as well as aquaculture. At room temperature, it appears as a solid, odorless, dark green powder, that yields a blue solution when dissolved in water.
Other Names
Trade names for methylene blue include Desmoid piller, Desmoidpillen, Panatone, Urolene Blue, and Vitableu. Its synonyms include Phenothiazine-5-ium, 3,7-bis(dimethylamino)-, chloride (9CI); C.I. Basic Blue 9 (8CI); methylthionine chloride; methylthioninium chloride; tetramethylthionine chloride; swiss blue; aizen methylene blue; C.I. 52015. Methylene blue should not be confused with methyl blue, another histology stain, new methylene blue, nor with the methyl violets often used as pH indicators.
Uses
Chemistry
Methylene blue is widely used a redox indicator in analytical chemistry meaning that it indicates the presence or absence of oxygen. Oxygen-rich environments are said to be oxidizing. Oxidizing chemicals, such as oxygen and chlorine, strip electrons away from atoms of other elements. Chemical elements that have such a strong attraction for electrons that they can take electrons away from other types of atoms are known as oxidizing agents, and are very useful in chemistry. Methylene blue indicates the presence of oxidizing agents because it is itself oxidized by these compounds. When electrons are stripped from methylene blue, the resulting molecule imparts a blue color to the solution—giving a clear sign of a chemical change.[2]
The redox properties can be seen in a classical demonstration of chemical kinetics in general chemistry, the "blue bottle" experiment. Typically, a solution is made of glucose, methylene blue, and sodium hydroxide. Upon shaking the bottle, the oxygen in solution oxidizes methylene blue, and the solution turns blue. The glucose will gradually reduce the methylene blue to its colorless (reduced) form. Hence, when the dissolved oxygen is entirely consumed, the solution will turn colorless.[3] Methylene blue is also used to make the reaction between Fehling's solution and reducing sugars more visible, and as a reagent in redox titrations in volumetric analysis.[4]
Biology
Methylene blue is commonly used by biologists as a dye that assists in the identification of bacteria. Because bacteria are practically colorless, adding a drop or two of methylene blue to a microscope slide enables the biologists to see bacterial shapes and structures. Dyes like methylene blue (referred to as stains in biology) work by binding to biological tissues as a result of chemical attractions. Methylene blue is at its deepest shade of blue when in contact with acids, which makes it very useful in the identification of nucleic acids, like DNA and RNA.[5] It can also work as an alternative to the chemical crystal violet in cellular structure|gram's staining procedures.[6]
Given this attraction to nucleic acids, methylene blue has also been used in procedures such as northern blotting/ northern hybridization (which is used for the detection of specific RNA sequences), in order to visualize RNA.[7] In addition, methylene blue is used as a safer alternative for another chemical called ethidium bromide (normally used in the visualization of DNA on gels in blotting procedures western blot. This is because ethidium bromide is a potent carcinogen and mutagen, and also because the short-length UV light that is required for ethidium bromide to fluoresce (and thereby aid in visualizing the DNA) can cause unwanted mutations in the DNA sample itself. Drawbacks of using methylene blue as a replacement are that it is less sensitive than ethidium bromide, and also fades rapidly after staining. This makes methylene blue an unideal replacement (though suitable for school contexts, due to it's less harmful nature). [8] Methylene blue has also been used as a way to obtain a quick estimate of the percentage of viable cells in a yeast sample, since viable yeast cells contain an enzyme that decolorizes methylene blue, whereas dead cells do not. As a result, when cells from a yeast are suspended in the dye, it penetrates all the cells, and leaves the dead cells blue, and the living cells unstained. Despite this, it must be noted that this method simply indicates whether an enzyme is present in the yeast cells (not whether the cells are incapable of dividing), and therefore is less accurate than other methods, and should be used to simply provide a rapid estimate. [9]
Medicine
Methylene blue has wide use in the medical community. It is employed as a treatment for methemoglobinemia, a disorder in which methemoglobin (oxidized hemoglobin) levels rise above their normal 1% in blood. Methemoglobin lacks the electron that is needed to form a bond with oxygen and, thus, is incapable of oxygen transport, meaning that, if there is too much methemoglobin in the blood, a person can die because of lack of oxygen to vital tissues and organs. Because of methylene blue's reducing abilities, it can reduce the excess methemoglobin to hemoglobin, thereby restoring normal methemoglobin levels. [10] Methylene blue can also be used as a stain for surgical and medical marking (though it can cause localized tissue inflammation), as well as a diagnostic agent in renal function tests and in vital nerve staining. It has also been used as an antidote for cyanide poisoning, but it should be used carefully, because it may make cyanide toxicity worse by increasing the amount of cyanide in the blood. [11] Sodium nitrite is considered to be a safer and more effective antidote.
The drug has also been used for the treatment of manic-depressive psychosis (schizophrenia), the herpes simplex, chronic urolithiasis (formation of kidney and bladder stones), and glutaricaciduria (a rare hereditary metabolic disorder, that results in the accumulation of excess organic acids in the blood and urine). Methylene blue was formerly used as as a urinary antiseptic, a treatment for cystitis (bladder infection) and urethritis (infection of the urethra), as well as an analgesic (painkiller) and antipyretic (fever reducer); however, there are more effective agents used now. In terms of its effectiveness as an antiparasitic, methylene blue has shown to have effects against malaria.
Aquaculture
Methylene blue is used in aquaculture and by tropical fish hobbyists as a bacterial and fungal infection preventative on freshwater fish eggs. It is also commonly used as a additive in a solution in which infected (or newly purchased) fish are dipped (commonly called a dip). In the dip, the methylene blue serves to fight and kill the offending organisms, as well as increase the oxygen carrying capacity of the fish's hemoglobin. [12] While some hobbyists use methylene blue to treat fish infected with ich, the parasitic[protozoa]] Ichthyophthirius multifiliis, methylene blue has shown to not be the most effective solution, and other solutions, such as ionized copper, are instead suggested. [13] While methylene blue is non-toxic to fish if used in the proper dosage, it is toxic to live plants, and also will harm fish if placed in long-term contact with them.
Other uses
Methylene blue has also been used as a dye for temporary hair colorants, cotton, wool, leather, and paper.
Misuse
While methylene blue has many uses in medicine, it has also been used inappropriately by pranksters, due to it's ability to alter urine with a green-blue color. About 75% of an oral dose of methylene blue is released into the urine (mostly in its reduced form - leucomethylene blue), thereby adding a blue-green hue to the urine (some of the remaining methylene blue is excreted via the bile). However, use of this substance in such a way is dangerous, because methylene blue is a biologically active substance[14], and if administered inappropriately, can lead to a number of health complications, including gastrointestinal disturbances and dysuria. Large doses of methylene blue can can produce methaemoglobinaemia, as well as chest pain, dyspnoea, restlessness, apprehension, tremors, a sense of oppression, urinary tract irritation, as well as a mild haemolysis with moderate hyperbilirubinaemia, reticulosis and slight anaemia.[15]
Notes
- ↑ SMILES is the acronym for Simplified Molecular Input Line Entry Specification
- ↑ Methylene Blue, Part 2: The Chemist's Indicator American Chemistry Council. December 2006. Retrieved July 20, 2007.
- ↑ Redox behavior of methylene blue (blue bottle) Swiss Federal Institute of Technology Zurich Feb 12, 2007. Retrieved July 20, 2007.
- ↑ ISI 27-1e Determination of Reducing Power and DE by Lane and Eynon's method. International Starch Institute May 1999. Retrieved July 20, 2007.
- ↑ Methylene Blue, Part 1: The Biologist's Dye American Chemistry Council November 2006. Retrieved July 20, 2007.
- ↑ Wang, Nam Sun [http://www.eng.umd.edu/~nsw/ench485/lab9b.htm Experiment Number 9B CELL DIFFERENTIATION BY GRAM'S STAIN] Department of Chemical & Biomolecular Engineering University of Maryland Retrieved July 20, 2007.
- ↑ http://wheat.pw.usda.gov/~lazo/methods/iubio/northgel.html. Retrieved July 20, 2007.
- ↑ Madden, Dean. Safer Stains for DNA Bioscience explained 1.2 Retrieved July 20, 2007.
- ↑ Painting, K and Kirsophttp, B. A QUICK METHOD FOR ESTIMATING THE PERCENTAGE OF VIABLE CELLS IN A YEAST POPULATION, USING METHYLENE BLUE STAINING National Collection of Yeast Cultures, AFRC Institute of Food Research 1989. Retrieved July 20, 2007.
- ↑ Lee, David C and Tuyl, Anna van. Methemoglobinemia. Emedicine November 19, 2005. Retrieved July 20, 2007.
- ↑ Methylene blue (systemic) Drugs.com. Retrieved July 20, 2007.
- ↑ Ellis, Terry A. Dips Fishgeeks.com Retrieved July 20, 2007.
- ↑ Fenner, Bob. Methylene Blue, Safe, But Not Always Efficacious WetWebMedia.com Retrieved July 20, 2007.
- ↑ Carlson, John. Re: Students asked if methylene blue put into cookies as a prank was dangerous? Madsci network May 3, 1999. Retrieved July 20, 2007.
- ↑ Data sheet: Methylene Blue Solution for Injection Medsafe: New Zealand Medicines and Medical Devices safety authority February 2007. Retrieved July 20, 2007.
ReferencesISBN links support NWE through referral fees
- Schirmer H, Coulibaly B, Stich A, et al. (2003). Methylene blue as an antimalarial agent—past and future. Redox Rep. 8: 272–76.
- Meissner PE, Mandi G, Coulibaly B, et al. (2006). Methylene blue for malaria in Africa: results from a dose-finding study in combination with chloroquine. Malaria Journal 5: 84.
- National Toxicology Program The National Institute of Environmental Health Sciences. Retrieved July 20, 2007.
- Azmat, Rafia (2004) KINETICS OF METHYLENE BLUE WITH ORGANIC REDUCTANTS Pakistan Research Repository Retrieved July 20, 2007.
- Narsapur SL, Naylor GJ. Methylene blue. A possible treatment for manic depressive psychosis. J Affect Disord. 1983 May;5(2):155-61.
External links
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