Polysorbate 20 (common commercial brand names include Kolliphor PS 20, Scattics, Alkest TW 20, Tween 20, and Kotilen-20) is a
polysorbate-type
nonionic surfactant
Surfactants are chemical compounds that decrease the surface tension between two liquids, between a gas and a liquid, or interfacial tension between a liquid and a solid. Surfactants may act as detergents, wetting agents, emulsifiers, foa ...
formed by the
ethoxylation
Ethoxylation is a chemical reaction in which ethylene oxide adds to a substrate. It is the most widely practiced alkoxylation, which involves the addition of epoxides to substrates.
In the usual application, alcohols and phenols are converted i ...
of
sorbitan monolaurate. Its stability and relative nontoxicity allows it to be used as a
detergent
A detergent is a surfactant or a mixture of surfactants with cleansing properties when in dilute solutions. There are a large variety of detergents, a common family being the alkylbenzene sulfonates, which are soap-like compounds that are m ...
and
emulsifier
An emulsion is a mixture of two or more liquids that are normally immiscible (unmixable or unblendable) owing to liquid-liquid phase separation. Emulsions are part of a more general class of two-phase systems of matter called colloids. Althoug ...
in a number of domestic, scientific, and pharmacological applications. As the name implies the ethoxylation process leaves the molecule with 20
repeat units of
polyethylene glycol
Polyethylene glycol (PEG; ) is a polyether compound derived from petroleum with many applications, from industrial manufacturing to medicine. PEG is also known as polyethylene oxide (PEO) or polyoxyethylene (POE), depending on its molecular w ...
; in practice these are distributed across 4 different chains, leading to a commercial product containing a range of chemical species.
Food applications
Polysorbate 20 is used as a
wetting agent
Surfactants are chemical compounds that decrease the surface tension between two liquids, between a gas and a liquid, or interfacial tension between a liquid and a solid. Surfactants may act as detergents, wetting agents, emulsifiers, foaming a ...
in flavored mouth drops such as Ice Drops, helping to provide a spreading feeling to other ingredients like
SD alcohol and mint flavor.
The
World Health Organization
The World Health Organization (WHO) is a specialized agency of the United Nations responsible for international public health. The WHO Constitution states its main objective as "the attainment by all peoples of the highest possible level o ...
has suggested acceptable daily intake limits of 0–25 mg of polyoxyethylene sorbitan esters per kg body weight.
Biotechnical applications
In biological techniques and sciences, polysorbate 20 has a broad range of applications. For example, it is used:
* as a washing agent in
immunoassay
An immunoassay (IA) is a biochemical test that measures the presence or concentration of a macromolecule or a small molecule in a solution through the use of an antibody (usually) or an antigen (sometimes). The molecule detected by the immunoass ...
s, such as
Western blot
The western blot (sometimes called the protein immunoblot), or western blotting, is a widely used analytical technique in molecular biology and immunogenetics to detect specific proteins in a sample of tissue homogenate or extract. Besides detec ...
s and
ELISA
The enzyme-linked immunosorbent assay (ELISA) (, ) is a commonly used analytical biochemistry assay, first described by Eva Engvall and Peter Perlmann in 1971. The assay uses a solid-phase type of enzyme immunoassay (EIA) to detect the presence ...
s. It helps to prevent non-specific antibody binding. In this major application, it is dissolved in
Tris-buffered saline or
phosphate buffered saline at dilutions of 0.05% to 0.5% v/v. These buffers are used for washes between each immunoreaction, to remove unbound immunologicals, and eventually for incubating solutions of immunoreagents (labeled antibodies) to reduce nonspecific background.
* to saturate binding sites on surfaces (i.e., to coat polystyrene microplates, generally combined with proteins such as BSA).
* to stabilize proteins
purified protein derivative (PPD) solution used in skin testing for
tuberculosis
Tuberculosis (TB) is an infectious disease usually caused by ''Mycobacterium tuberculosis'' (MTB) bacteria. Tuberculosis generally affects the lungs, but it can also affect other parts of the body. Most infections show no symptoms, in w ...
exposure
* as a solubilizing agent of
membrane
A membrane is a selective barrier; it allows some things to pass through but stops others. Such things may be molecules, ions, or other small particles. Membranes can be generally classified into synthetic membranes and biological membranes. ...
proteins
* for
lysing
Lysis ( ) is the breaking down of the membrane of a cell, often by viral, enzymic, or osmotic (that is, "lytic" ) mechanisms that compromise its integrity. A fluid containing the contents of lysed cells is called a ''lysate''. In molecular bio ...
mammalian cells, at a concentration of 0.05% to 0.5% v/v, generally combined with other detergents, salts and additives.
Pharmaceutical applications
Polysorbate 20 is used as an
excipient
An excipient is a substance formulated alongside the active ingredient of a medication, included for the purpose of long-term stabilization, bulking up solid formulations that contain potent active ingredients in small amounts (thus often referred ...
in pharmaceutical applications to stabilize
emulsion
An emulsion is a mixture of two or more liquids that are normally immiscible (unmixable or unblendable) owing to liquid-liquid phase separation. Emulsions are part of a more general class of two-phase systems of matter called colloids. Althou ...
s and
suspensions.
Industrial and domestic applications
Polysorbate 20 is used in many brands of baby wipes.
Polysorbate 20 is used by
philatelists
Philately (; ) is the study of postage stamps and postal history. It also refers to the collection and appreciation of stamps and other philatelic products. Philately involves more than just stamp collecting or the study of postage; it is possi ...
to remove stamps from envelopes and to remove residues from stamps, without harming the stamp itself.
Polysorbate 20 is also used as wetting agent in rubber balers in the
elastomer
An elastomer is a polymer with viscoelasticity (i.e. both viscosity and elasticity) and with weak intermolecular forces, generally low Young's modulus and high failure strain compared with other materials. The term, a portmanteau of ''elastic ...
industry.
Polysorbate 20 has been used as a shape directing agent to synthesize spheroidal
magnetite
Magnetite is a mineral and one of the main iron ores, with the chemical formula Fe2+Fe3+2O4. It is one of the oxides of iron, and is ferrimagnetic; it is attracted to a magnet and can be magnetized to become a permanent magnet itself. With ...
nanoassemblies.
[Q. Maqbool, C. Singh, A. Paul and A. Srivastava ''J. Mat. Chem. C'', 2015, 3, 1610]
See also
*
Polysorbate 80
References
{{reflist
External links
Tween 20 on biologists' wiki OpenWetWare
Non-ionic surfactants
Excipients
Laurate esters
E-number additives