Sodium monofluorophosphate

Sodium monofluorophosphate (also disodium monofluorophosphate or MFP) is a chemical with the formula Na₂PO₃F. Its molecular weight is 143.95 g/mol. Typical for a salt, MFP is odorless, colorless, and water-soluble. It melts at 625 ºC. Image File history File links Sodium_monofluorophosphate. ...

Uses of MFP

MFP is best known as an ingredient in toothpastes for both humans and animals. It is claimed to protect tooth enamel from attack by bacteria that cause dental caries (cavities). Though developed by a chemist at Procter and Gamble, its use in toothpaste (Colgate toothpaste) was patented by Colgate-Palmolive, as Procter and Gamble was engaged in the marketing of Crest toothpaste (containing stannous fluoride). Modern toothpaste gel Toothpaste is a paste or gel used to clean and improve the aesthetic appearance of teeth. ... Colgate redirects here. ... Colgate-Palmolive Company NYSE: CL is a multinational corporation in the business of the provision of products such as soaps, detergents, and oral hygiene products such as toothpaste and toothbrushes. ... Procter & Gamble Co. ... Tube of Crest Crest is a brand of toothpaste made by Procter & Gamble which is now on the market in many countries, such as the United States, Canada, the United Kingdom, and France. ...

MFP is also used in some medications for the treatment of osteoporosis. Osteoporosis is a disease of bone in which bone mineral density (BMD) is reduced and bone microarchitecture is disrupted. ...

In 1991, sodium monofluorophosphate was found by Calgon to inhibit the solubility of lead in drinking water when used in concentrations between 0.1 mg/L and 500 mg/L.^[1] Calgon is a brand registered trademark of two different corporations. ... This article is about the chemical element. ...

Tooth Decay

Tooth decay is caused by bacteria normally present in everyone's mouth. These bacteria form a sticky, colorless soft film on the teeth called plaque. When foods containing carbohydrates (starches and sugars) are eaten, the bacteria that form plaque use the sugar as a form of energy. They also turn it into a glue-like substance that helps them stick to the surface of the tooth. The plaque produces acid as it eats up the sugar, which creates holes in the enamel.^[2] The word plaque can have different connotations and can also be spelt placque: Look up Plaque on Wiktionary, the free dictionary Dental plaque is a yellowish biofilm that builds up on the teeth formed by bacteria embedded in a matrix of polymers of bacterial and salivary origin. ... Carbohydrates are chemical compounds that contain oxygen, hydrogen, and carbon atoms. ... Starch is a complex carbohydrate which is insoluble in water. ... Magnified view of refined sugar crystals. ... It has been suggested that strong acid be merged into this article or section. ... Tooth enamel is the hardest and most mineralized substance of the body , and with dentin and cementum is one of the three major parts of the tooth. ...

Tooth enamel consists mostly of calcium hydroxyphosphate, Ca₅(PO₄)₃OH, also known as apatite. Apatite is a very hard, insoluble compound. However, saliva sometimes becomes more acidic, particularly after a person eats a high-sugar meal. Acids ionize to produce hydronium ions, H₃O⁺(more commonly written H⁺), which react with the hydroxide ion, OH^-, in the apatite to form water. Apatite is a group of phosphate minerals, usually referring to: hydroxylapatite, fluorapatite, and chlorapatite, named for high concentrations of OH-, F-, or Cl- ions, respectively, in the crystal lattice. ... Saliva, often informally known as spit, is the moist, clear, and usually somewhat frothy substance produced in the mouths of some animals, including humans. ...

Ca₅(PO₄)₃OH_(s) + H⁺_(aq) → Ca₅(PO₄)_3(aq) + H₂O_(l)

The loss of OH^- causes the apatite to dissolve. Saliva supplies more OH^- ions and new apatite is formed, but slowly. If fluoride, F^-, ions are present in saliva, some fluorapatite, Ca₅(PO₄)₃F, also forms. Apatite is a group of minerals, usually referring to: hydroxylapatite, fluorapatite, and chlorapatite, named for high concentrations of OH-, F-, or Cl- ions, respectively, in the crystal lattice. ...

Ca₅(PO₄)₃OH^-_(aq) + F^-_(aq) → Ca₅(PO₄)₃F_(s)

Fluorapatite resists attacks by acids, so the tooth enamel resists decay better than enamel containing no fluoride.^[3]

Preparation

MFP may be prepared by heating a difluorophosphate solution in dilute sodium hydroxide. Flash point non flammable Supplementary data page Structure and properties n, εr, etc. ...

PO₂F₂^2-_(aq) + 2 NaOH_(aq) → Na₂PO₃F_(aq) + 2 HF_(aq)

Discovery and Development

Sodium monofluorophosphate was first described in 1929 by the German chemist Dr. Willy Lange, who was then with the University of Berlin. His fruitless attempts to prepare the free monofluorophosphoric acid led him to check the stability of its esters. Together with Gerda von Krueger, one of his students, Lange thus synthesized diethyl fluorophosphate and some analogs, which proved to be quite toxic; the first nerve agents were discovered. In the 1930's, Gerhard Schrader, working for the German company IG Farben, tried to develop synthetic insecticide. His work focused on esters of phosphoric acid and resulted in an accidental discovery of some other nerve agents such as DFP (= di-isopropyl fluorophosphate), Tabun, Soman, and Sarin. In the meantime, Lange -who was married to a Jewish woman- emigrated from Germany to the United States and started work for Procter and Gamble Company. In 1947, he and Ralph Livingston of Monsanto Company published reports on the preparation of the free fluorophosphoric acids and mentioned the use of some toxic esters of monofluorophosphoric acid (like DFP) in the treatment of glaucoma and myasthenia gravis. The well known toxicity of these esters led to fears that the simple salts might also be toxic, and such fears precluded any large scale commercial use of the salts. In 1950, under sponsorship of the manufacturer of the compounds, Ozark Chemical Company, the toxicity of sodium monofluorophosphate was studied by Harold C. Hodge at the University of Rochester who included anti-cavity testing. In 1967 Colgate-Palmolive filed several patents on the use of sodium monofluorophosphate in toothpaste.^[4] Dr. Gerhard Schrader (25 Feb. ... IG Farben (short for Interessen-Gemeinschaft Farbenindustrie AG) was a German conglomerate of companies formed in 1925 and even earlier during World War I. IG Farben held nearly a total monopoly on the chemical production, later during the time of Nazi Germany. ... Insecticide application by crop spraying An insecticide is a pesticide whose purpose is to kill or to prevent the multiplication of insects. ... Tabun or GA (Ethyl N,N-dimethylphosphoramidocyanidate) is an extremely toxic substance that is one of the worlds most dangerous weapons of war. ... Procter & Gamble Co. ... Monsanto Company (NYSE: MON) is a multinational agricultural biotechnology corporation. ... Myasthenia gravis (MG, Latin: grave muscle weakness) is a neuromuscular disease leading to fluctuating weakness and fatiguability. ... Located in Rochester, New York, USA and founded in 1850, the University of Rochester is a private, coeducational and nonsectarian research institution. ... Colgate-Palmolive Company NYSE: CL is a multinational corporation in the business of the provision of products such as soaps, detergents, and oral hygiene products such as toothpaste and toothbrushes. ...

Content and Toxicity

The usual content of MFP in toothpaste is 0.76%. It is not used for water fluoridation. Currently accepted research indicates that by using such toothpaste, cavities may be reduced 17-38%.

The compound is not very toxic. (LD₅₀ in rats = 0.9 g/kg).

Structure of Fluorophosphate

The structure of the fluorophosphate anion consists of phosphorus at the center of a tetrahedron defined by three oxygen atoms and one fluorine. Formal representations depict a double bond between one oxygen atom and phosphorus, with single bonds for the other two oxygen atoms and the fluorine. In this very formal depiction, negative charge is localized on the O atoms of the single P-O bonds. MFP is similar to and isoelectronic with Na₂SO₄. This article is about the chemical element. ... General Name, Symbol, Number oxygen, O, 8 Chemical series Nonmetals Group, Period, Block 16, 2, p Appearance colorless Atomic mass 15. ... General Name, Symbol, Number fluorine, F, 9 Chemical series halogens Group, Period, Block 17, 2, p Appearance pale greenish-yellow gas Atomic mass 18. ... Two or more molecular entities (atoms, molecules, ions) are described as isoelectronic if they have the same number of valence electrons and the same structure (number and connectivity of atoms), but may differ in the elements involved. ...

Fun Fact

One kilogram of MFP costs about US$32 (UK£18).

References

1. ↑ Peter Meiers Monofluorophosphate History
2. ↑ Healthy Teeth [1]
3. ↑ Davis, R. E., Ph.D., Metcalfe, H. C., Williams, J. E., Castka, J. F. (1999). Modern Chemistry. Austin, TX: Harcourt Brace & Company.
4. ↑ Peter Meiers Monofluorophosphate History