Tween (or polysorbate) is a non-ionic surfactant with an odor, warm and slightly bitter. It is a series of polyoxyethylene dehydrated sorbates. Partial fatty acid esters of alcohols. Widely used as emulsifier and solubilizer for oil substances.
Tween has the following functions and uses:
1. Emulsified proteins in biological experiments, when used, Tween and the same type of TritonX-1OO (Polyethylene glycol octylphenyl ether) non-ionic detergent does not destroy the structure of proteins and can reduce damage to the original interactions between proteins. Ionic detergents such as SDS destroy the protein structure.
2. As a blocking agent in biological experiments, the blocking agent should block all unbound sites without replacing the target protein on the membrane, not binding to the target protein label, and not interacting with the antibody or detection Reagents are cross-reactive. Tween 20 has the function of refolding antigen and can improve specific recognition ability. When doing westernblot, use inert protein or non-ionic detergent to block unbound sites on the membrane to reduce non-specific binding of the antibody. The most common blocking agents are BSA, skim milk powder, casein, gelatin, and dilute solutions of Tween 20 (0.05–0.1%).
3. Often used as an oil-in-water (O/W) emulsifier to disperse other substances evenly in the solution. It is mainly used in pesticides, food, and cosmetics. Combined with other emulsifiers such as sodium lauryl sulfate or Span, it can increase the stability of the emulsion. Tween can be used to emulsify essential oils and dissolve them in aqueous liquids, making them fully functional. Relatively speaking, Tween 20 is milder, while Tween 80 is more emulsifying.
4. Medicinal uses: (1) Can be used as a solubilizer for certain drugs. (2) It has hemolytic effect, with Tween-80 having the weakest effect. (3) The aqueous solution can become turbid when heated and becomes clear after cooling, without affecting the quality. (4) It can interfere with the effect of bacteriostatic agents in solution.
