Polyoxyethylene-sorbitane monolaureate

D Polyoxyethylene carbohydrate-20 Fatty alkylester D1 Polyoxyethylene sorbitan monolaurate, TWEEN... 

Egelrud and Olivecrona (1973) studied the catalytic activity against several substrates of bovine milk enzyme preparations that had been purified about 7000-fold to a purity higher than 80% (Egelrud and Olivecrona 1972). The enzyme catalyzed the hydrolysis of emulsified trioleate, trioctanoate, monooleate, Tween 20 (polyoxyethylene sorbitan monolaurate), and p-nitrophenyl acetate. It was concluded that the enzyme had rather low substrate specificity and that the presence of activating serum factors is not needed for catalysis to occur. 

More recently, Carafa et al. showed that niosomes could be obtained from polyoxyethylene sorbitan monolaurate-cholesterol in aqueous environment. These authors investigated the delivery of lidocaine HC1 and lidocaine base from vesicles through silicone membrane and nude mice skin [44]. It was found that only the charged molecule (loading pH 5.5) could be encapsulated within the vesicles ( 30%). This behavior was explained by the entrapment ability of the hydrophilic moiety within the aqueous core of the vesicles. The lipophilic unionized form of lidocaine (loading pH 8.6) remained unattached. The amount of lidocaine permeated through nude mice skin from these niosomes was similar to liposomes and only about twofold greater than from a micellar system. 

The polysorbates used most regarding efflux pump inhibition are polyoxyethylene sorbitan monolaurates (Tween 20), polyoxyethylene sorbitan monopalmi-tates (Tween 40) and polyoxyethylene sorbitan monooleates (Tween 80). Various studies demonstrate the ability of polysorbates to inhibit efflux pumps. In transport experiments across intestinal mucosa, the efflux ratio (basolateral to apical drug transport/apical to basolateral drug transport) of rhodamine 123 was reduced in the presence of Tween 80 (Shono et al. 2004). In another study, Zhang et al. demonstrated enhanced absorption of the P-glycoprotein substrate digoxin in rats in the presence of Tween 80 (Zhang et al. 2003). 

Polyoxyethylene sorbitan monolaurate (Polysorbate 20 or Tween 20) 0 II CH20(CH Hfi)z1CH2CH20—C CH2(CH2)9CH3 I... 

Polyoxyethylene sorbitan monolaurate Dodecyl ether of polyoxyethylene glycol Polyoxyethylene polyoxypropylene polyol Polyoxyethylene glycol 400 monolaurate Anionic surfactants... 

The presence of 0.1%(v/v) of polyoxyethylene sorbitan monolaurate (Tween-20) in all buffers during the processing of the membrane asasts the prevention of nonspecific binding. 

Polyoxyethylene sorbitan monolaurate Emulsifying agent, solubilizing agent, surfactant iv, im, sc... 

PBST (PBS plus 0.1% Polyoxyethylene sorbitan monolaurate (Tween 20 Sigma). 

Changes in protein volume during the displacement of a spread p-lactoglobulin from an air-water interface by the nonionic surfactant (polyoxyethylene sorbitan monolaurate) Tween 20. 

Competitive displacement of spread (3-lactoglobulin from an air-water interface by (a) nonionic and (b) ionic surfactants. The collapse of the protein network is indicated by showing the change in area occupied by the protein at the interface as a function of surface pressure, (a) Data for A-Tween 20 (polyoxyethylene sorbitan monolaurate) and B-Tween 60 (polyoxyethylene sorbitan momostearate). (b) Data for A-cetyl-trimethyl-ammonium bromide (CTAB), B-lyso-phosphatidylcholinelauroyl (LPC-L), and -sodium dodecyl sulphate (SDS). 

AFM images showing the displacement of a spread (3-lactoglobulin protein film from an air-water interface by the progressive addition of surfactant, (a) Displacement with (polyoxyethylene sorbitan monolaurate) Tween 20, surface pressure Tr=22.5mN/m, image size 3.2 X 3.2 jam. (b) Displacement with cetyl-trimethyl-ammonium bromide (CTAB), TT = 22.8 mN/m, image size 1x1 /rm. (c) Displacement with CTAB in the presence of 0.2 M sodium phosphate buffer, pH — 7, ir— 22.8 mN/m. scan size 1x1 /rm. Data are shown at similar surface pressures in order to allow comparison of domain sizes for ionic and nonionic surfactants. 

Comparison of the competitive displacement of spread films of whey protein isolate (WPI) and (3-lactoglobulin from an air-water interface with the nonionic surfactant (polyoxyethylene sorbitan monolaurate) Tween 20. Note that the WPI network remains intact at surface pressures (tt) above those at which the (3-lactoglobulm network has failed. The image sizes are indicated in brackets below the images. 

Amine oxide alkyl glycoside polyoxyethylene sorbitan monolaurate cocoethanolamide polyacrylamide... 

Abbreviations Tween 20, polyoxyethylene sorbitan monolaurate SDS, sodium dodecylsulfate DTABr, dodecyltrimethylammonium bromide. 

Additives used in final products Fillers carbon nanotubes, fumed silica, graphite. Fillers molybdenum disulfide, montmorlllonite, nanosilica, titanium dioxide, vanadium oxide Plasticizers dioctyl phthalate, ethylene carbonate, polyoxyethylene-sorbitane monolaureate, propylene carbonate, polyethylene and polypropylene glycols, tetraethylene glycol, tetraglyme Antislatics polyoxyethylene sorbitan monolaurate, polyoxyethylene glycol, polyoxyethylene octylphenyl ether ... 

Mahji, P.R. and Moulik, S.P. 1999 Physicochemical studies on biological macro- and microemulsions VI Mixing behaviours of eucalyptus oil, water and polyoxyethylene sorbitan monolaurate (Tween-20) assisted by -butanol and cinnamic alcohol, J. Disp. Sci. Technol. 20 1407-1427. 

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