Polyvinylpolypyrrolidone
Encyclopedia
Polyvinylpolypyrrolidone (Polyvinyl Polypyrrolidone, PVPP, crospovidone, crospolividone or E1202) is a highly cross-link
Cross-link
Cross-links are bonds that link one polymer chain to another. They can be covalent bonds or ionic bonds. "Polymer chains" can refer to synthetic polymers or natural polymers . When the term "cross-linking" is used in the synthetic polymer science field, it usually refers to the use of...

ed modification of polyvinylpyrrolidone (PVP).

The cross-link
Cross-link
Cross-links are bonds that link one polymer chain to another. They can be covalent bonds or ionic bonds. "Polymer chains" can refer to synthetic polymers or natural polymers . When the term "cross-linking" is used in the synthetic polymer science field, it usually refers to the use of...

ed form of PVP is used as a disintegrant (see also excipient
Excipient
An excipient is generally a pharmacologically inactive substance used as a carrier for the active ingredients of a medication. In many cases, an "active" substance may not be easily administered and absorbed by the human body; in such cases the substance in question may be dissolved into or...

s) in pharmaceutical tablets..
Basically, PVPP is a highly cross-linked version of PVP, which makes it insoluble in water but it still absorbs water and swells very rapidly and generates a swelling force. That is why it can be used as a disintegrant in tablet
Tablet
A tablet is a pharmaceutical dosage form. It comprises a mixture of active substances and excipients, usually in powder form, pressed or compacted from a powder into a solid dose...

s.

PVPP can be used as a drug, taken as a tablet
Tablet
A tablet is a pharmaceutical dosage form. It comprises a mixture of active substances and excipients, usually in powder form, pressed or compacted from a powder into a solid dose...

 or suspension
Suspension (chemistry)
In chemistry, a suspension is a heterogeneous fluid containing solid particles that are sufficiently large for sedimentation. Usually they must be larger than 1 micrometer. The internal phase is dispersed throughout the external phase through mechanical agitation, with the use of certain...

 to absorb compounds (so-called endotoxin
Endotoxin
Endotoxins are toxins associated with some Gram-negative bacteria. An "endotoxin" is a toxin that is a structural molecule of the bacteria that is recognized by the immune system.-Gram negative:...

s) causing diarrhoea. (Cf. bone char
Bone char
Bone char, also known as bone black, ivory black, animal charcoal, or abaiser, is a granular material produced by charring animal bones. To prevent the spread of mad-cow disease, the skull and spine are never used...

, charcoal
Charcoal
Charcoal is the dark grey residue consisting of carbon, and any remaining ash, obtained by removing water and other volatile constituents from animal and vegetation substances. Charcoal is usually produced by slow pyrolysis, the heating of wood or other substances in the absence of oxygen...

.)

It is also used as a fining to extract impurities (via agglomeration followed by filtration). It is used in winemaking
Winemaking
Winemaking, or vinification, is the production of wine, starting with selection of the grapes or other produce and ending with bottling the finished wine. Although most wine is made from grapes, it may also be made from other fruit or non-toxic plant material...

. Using the same principle it is used to remove polyphenols in beer
Beer
Beer is the world's most widely consumed andprobably oldest alcoholic beverage; it is the third most popular drink overall, after water and tea. It is produced by the brewing and fermentation of sugars, mainly derived from malted cereal grains, most commonly malted barley and malted wheat...

 production and thus clear beers with stable foam are produced. One such commercial product is called Polyclar®. PVPP formed bonds similar to peptidic bonds in protein (especially, like proline
Proline
Proline is an α-amino acid, one of the twenty DNA-encoded amino acids. Its codons are CCU, CCC, CCA, and CCG. It is not an essential amino acid, which means that the human body can synthesize it. It is unique among the 20 protein-forming amino acids in that the α-amino group is secondary...

 residues) and that is why it can precipitate tannin
Tannin
A tannin is an astringent, bitter plant polyphenolic compound that binds to and precipitates proteins and various other organic compounds including amino acids and alkaloids.The term tannin refers to the use of...

s the same way as proteins do.

PVPP has E number
E number
E numbers are number codes for food additives that have been assessed for use within the European Union . They are commonly found on food labels throughout the European Union. Safety assessment and approval are the responsibility of the European Food Safety Authority...

 code E1202 and is used as a stabiliser
Stabiliser (food)
A stabiliser is an additive to food which helps to preserve its structure. Typical uses include preventing oil/water emulsions from separating in products such as salad dressing; preventing ice crystals from forming in frozen food such as ice cream; and preventing fruit from settling in products...

.
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