Polysorbate 20

Polysorbate 20 (commercially also known as Tween 20) is a polysorbate surfactant whose stability and relative non-toxicity allows it to be used as a detergent and emulsifier in a number of domestic, scientific, and pharmacological applications. It is a polyoxyethylene derivative of sorbitan monolaurate, and is distinguished from the other members in the Tween range by the length of the polyoxyethylene chain and the fatty acid ester moiety. The commercial product contains a range of chemical species.

Food applications
Tween is used as a wetting agent in flavored mouth drops such as Ice Drops, helping to provide the spreading feeling of the other ingredients like SD alcohol and mint flavor.

The World Health Organization has suggested acceptable daily intake limits of 0-25 mg of polyoxyethylene sorbitan esters per kg body weight.

Biological applications
In the biological sciences, Tween 20 has a broad range of applications. For example, it is used:
 * to stabilize purified protein derivative (PPD) solution used in skin testing for tuberculosis exposure
 * as a blocking agent in immunoassays, such as Western blots and ELISAs.
 * as a solubilizing agent of membrane proteins
 * for lysing mammalian cells, at a concentration of 0.05% to 0.5% v/v.
 * can be dissolved in Tris-Buffered Saline or Phosphate buffered saline at dilutions of 0.05% to 0.5% v/v and used as a washing solution for immunoassays.

Pharmaceutical applications
Tween is used as in pharmaceutical applications to stabilize emulsions and suspensions.

Industrial and domestic applications
The Clorox-made cleaning solution used by the iRobot Scooba floor-washing robot lists Tween 20 as one of its major ingredients on its MSDS.

Data
Tween 20's cmc is 8.04&times;10-5 M at 21°C.