Тиогликолевая кислота: свойства и применение

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| Watchedfields = changed
| verifiedrevid = 470607208
| Reference =
| Name = Thioglycolic acid
| ImageFile Ref =
| ImageFile = Thioglycolic acid. png
| ImageSize = 150px
| ImageFile1 = Thioglycolic acid van der waals. png
| ImageSize1 = 150px
| ImageName1 = Space filling model of thioglycolic acid
| PIN = Sulfanylacetic acid
| OtherNames = 2 Sulfanylacetic acid2 Mercaptoacetic acidAcetyl mercaptanMercaptoacetateMercaptoacetic acidThioglycolic acidThiovanic acid
|Section1=
|Section2=Chembox Properties
| C=2 | H=4 | O=2 | S=1
| Density = 1.32 g/cm3
| MeltingPtC = −16
| BoilingPtC = 96
| BoilingPt notes = at 5 mmHg
| Appearance = colorless, clear liquid
| ExploLimits = 5.9% TGA is miscible with polar organic solvents.

TGA is used as a chemical depilatory and is still used as such, especially in salt forms, including calcium thioglycolate and sodium thioglycolate. TGA is the precursor to ammonium thioglycolate, which is used for permanents. TGA and its derivatives break the disulfide bonds in the cortex of hair. One reforms these broken bonds in giving hair a "perm". Alternatively and more commonly, the process leads to depilation, as is done commonly in leather processing. It is also used as an acidity indicator, manufacturing of thioglycolates, and in bacteriology for preparation of thioglycolate media. TGA has also been used to soften nails, either to reshape pincer nails into the correct position or to help topical antifungals penetrate the nail. Organotin derivatives of thioglycolic acid isooctyl esters are widely used as stabilizers for PVC. These species have the formula R2Sn(SCH2CO2C8H17)2. or "wheel cleaner" to remove iron oxide residue from wheels. Ferrous iron combines with thioglycolate to form red violet ferric thioglycolate.

Thioglycolic acid with a pKa of 3.83

Scientist David R. Goddard, in the early 1930s, identified TGA as a useful reagent for reducing the disulfide bonds in proteins, including keratin (hair protein), while studying why protease enzymes could not easily digest hair, nails, feathers, and such. He realized that while the disulfide bonds, which stabilize proteins by cross linking, were broken, the structures containing these proteins could be reshaped easily, and that they would retain this shape after the disulfide bonds were allowed to re form. TGA was developed in the 1940s for use as a chemical depilatory.

The LD50 (oral, rat) is 261 mg/kg, Mercaptoacetic acid in hair waving and depilatory products containing other mercapto acids can be identified by using thin layer chromatography and gas chromatography. MAA also has been identified by using potentiometric titration with silver nitrate solution.