Fluorides are found in a wide range of chemicals that occur both naturally and artificially. Some examples of how fluorides are used include:
- Hydrofluoric acid – This is one of the most important fluorides in industry. It is mainly used in the production of fluorocarbons and aluminium fluorides. Hydrofluoric acid can dissolve glass.
- Fluorides can act as enzyme inhibitors. They are commonly used to inhibit the activity of phosphatases such as the serine/threonine phosphatases. Many of the fluoride salts possess this ability. They can inhibit the enzymes through replacement of the nucleophilic hydroxyl ions presents on the active sites of these enzymes. Beryllium fluoride and aluminium fluoride are phosphatase inhibitors that can imitate the phosphate group and function as analogues of the transition state of the reaction.
- The inorganic fluoride sulfur hexafluoride is a nontoxic insulator used in electrical transformers. Uranium hexafluoride is an inorganic fluoride used to separate uranium isotopes when creating nuclear reactor fuel or atom bombs.
- Fluorides are also used as fluoropolymers such as polytetrafluoroethylene or Teflon. Teflon is an inert and biocompatible material that is used in a wide range of applications such as surgical implants, cosmetic surgery and reconstructive surgery. Teflon is also used in paints and cookware. The fluoropolymer fabric Gore-Tex is used to make outdoor protective clothing.
- Fluorides play an important role in the prevention of tooth decay and may be applied locally in the form of toothpaste or ingested through drinking fluoridated water. Previously, sodium chloride was added to drinking water but now common additives include hexafluorosilicic acid (H2SiF6) and sodium hexafluorosilicate (Na2SiF6).
- Imaging studies – Fluoride-containing dyes and contrast mediums such as fluorodeoxyglucose are used in imaging studies such as positron emission tomography. The chemical is labelled with the radioactive isotope fluorine-18, which emits positrons when it decays into 18O.
- Examples of medications that contain fluorides include the antibiotic ofloxacin, the HIV protease inhibitor tipranavir, the antipsychotic fluphenazine and the general anesthetic halothane.
Reviewed by Sally Robertson, BSc