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Tween Sorbitan monooleate

Adsorption of t-PA to process equipment surfaces consisting of either stainless steel or glass was minimized by adding the detergent polyoxyethylene sorbitan monooleate (Tween 80) to the semm-free culture conditioned media at 0.01% (vol/vol). The equipment was also rinsed, before use, with phosphate buffered saline (PBS) containing 0.01% Tween 80. Hydrophilic, plastic equipment was used whenever possible. AH buffers were sterile filtered. Sterile filtration of Hquids and gases is usually carried out using 0.2 or 0.45 p.m filters. [Pg.46]

Zhong et al. (2003) studied the apparent solubility of trichloroethylene in aqueous solutions, where the experimental variables were surfactant type and cosolvent concentration. The surfactants used in the experiment were sodium dihexyl sulfo-succinte (MA-80), sodium dodecyl sulfate (SDS), polyoxyethylene 20 (POE 20), sorbitan monooleate (Tween 80), and a mixture of Surfonic- PE2597 and Witconol-NPIOO. Isopropanol was used as the alcohol cosolvent. Eigure 8.20 shows the results of a batch experiment studying the effects of type and concentration of surfactant on solubilization of trichloroethylene in aqueous solutions. A correlation between surfactant chain length and solubilization rate may explain this behavior. However, the solubilization rate constants decrease with surfactant concentration. Addition of the cosolvent isopropanol to MA-80 increased the solubility of isopropanol at each surfactant concentration but did not demonstrate any particular trend in solubilization rate of isopropanol for the other surfactants tested. In the case of anionic surfactants (MA-80 and SDS), the solubility and solubilization rate increase with increasing electrolyte concentration for all surfactant concentrations. [Pg.172]

Low-molecular-weight surfactants ( emulsifiers ) are important ingredients in food products. The types of surfactants most commonly studied in food colloids research are phospholipids (lecithin), mono/diglycerides (particularly glycerol monostearate), polysorbates (Tweens), sorbitan monostearate or monooleate (Spans), and sucrose esters. These small lipid-based amphiphiles can typically lower the interfacial tension to a greater extent than the macromolecular amphiphiles such as proteins and certain gums (Bos and van Vliet, 2001). [Pg.323]

Patel N, Kostenbauder HB. Interaction of preservatives with macromolecules I binding of parahydroxybenzoic acid esters by polyoxyethylene 20 sorbitan monooleate (Tween 80). J Am Pharm Assoc (Sci) 1958 47 289-293. [Pg.108]

The overall objective of this research was to evaluate the effects of cosolvent addition on the ability of an ethoxylated nonionic surfactant to recover PCE from a heterogeneous, 2-D system. The specific tasks of this work were to (a) quantify the PCE solubilization rate and capacity in the presence and absence of a representative cosolvent (EtOH) and (b) investigate the effects of EtOH addition on surfactant delivery, plume migration and PCE recovery in a 2-D, layered sand tank. A representative nonionic surfactant, polyoxyethylated (POE) (20) sorbitan monooleate (Tween 80), was selected for study because of its capacity to solubilize PCE ( 0.7 g PCE/g surf at 20°C) and relatively high interfacial tension with PCE (5 dynes/cm). EtOH was chosen as the representative cosolvent because of its relatively low density (p = 0.79 g/cm1) and regulatory acceptance. [Pg.287]

Polyoxyethylene (POE) (20) sorbitan monooleate (Tween 80, Lot 36218, ICI Surfactants, Inc.) was used as received with no further purification. The average molecular weight of Tween 80 is 1310 g/mole, the density is 1.07 g/cm3, the hydrophile-lipophile balance (HLB) is 15, the critical micelle... [Pg.287]

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). [Pg.129]

Tween 80 (also known as At-Plus 109 and Polysorbate 80) is a polyoxyethylene sorbitan monooleate and was obtained from Atlas Chemical Industries, Inc. This nonionic surfactant has an HLB (hydrophile-lipophile balance) of 15.0 and is used as an emulsifier, solubilizer, and dispersant. It was used without further purification at the 0.1% (w/v) level in partitioning and greenhouse herbicidal evaluations as described below. [Pg.195]

Surfactant. Polyoxyethylene (20) sorbitan monooleate (also known as Tween 80, At-Plus 109, or Polysorbate 80) was obtained from Atlas Chemical Industries and used as received. It was used at the 0.1% (w/v) concentration level in all herbicidal activity evaluations and partitioning studies requiring the use of surfactant. [Pg.261]

Polysorbates are surfactants that are pegylated derivatives of sorbitan monoesters (i.e., monolaurate, monopalmitate, monostearate, monooleate, or monoisostearate) or sorbitan triesters (i.e., tristearate or trioleate) and are available in many grades. Poly-sorbate 80, also known as Tween 80, is a mixture of polyoxyethylene 20 sorbitan monooleates and is a yellow viscous liquid at room temperature. Sorbitan monooleate, also known as Span 80, is a yellow viscous... [Pg.3346]

Nickel (Ni-1) and palladium (Pd-2) complexes were employed for suspension polymerization of MMA in the presence of a small amount (1—5 wt %) of sorbitane monooleate polyethylene glycol) (20) (Tween 80) as a surfactant.132,137 The obtained polymer had controlled molecular weights and moderate MWDs = 1.4 —1.7) similarly to those obtained in toluene, although there was no detailed analysis on the size of the particles. [Pg.479]

Phenanthrene biomineralization, solubilization, and surface-tension data for the polyoxyethylene sorbitan monooleate surfactant, Tween 80, are shown in Figures 8, 9, and 10, respectively. Tween 80 completely inhibits phenan-... [Pg.352]

Ethanol/PG/PEG/Cremophor EL/Sorbitan monooleate/ Tween 80 Cyclosporin A/Gengraf ... [Pg.266]

Any pair of emulsifying agents that fall at opposite ends of the HLB scale - for example. Tween 80 (sorbitan monooleate with 20 mol EO, HLB = 15) and Span 80 (sorbitan monooleate, HLB = 5) - can be taken and used in various proportions to cover a wide range of HLB numbers. The emulsions should be prepared in the same fashion, with a few percent of the emulsifying blend. The stability of the emulsions can then be assessed at each HLB number, either from the rate of coalescence or qualitatively by measuring the rate of oil separation. In this way it should be possible to determine the optimum HLB number for a given oil. Subsequently, having found the most effective HLB value, various other surfactant pairs can be compared at this HLB value to identify the most effective pair. [Pg.185]

Tween 80 Brij 52 Polyoxyethylene (20) sorbitan monooleate Polyoxyethylene Certyl ether 1310 331 9.9 x 10-6... [Pg.56]

Tween 80 poly(oxyethylene)2o-sorbitan-monooleate Tween 20 poly(oxyethylene)2o-sorbitan-monolaurate SSF simultaneous saccharification and fermentation... [Pg.354]

Enzyme activity loss because of non-productive adsorption on lignin surface was identified as one of the important factors to decrease enzyme effectiveness, and the effect of surfactants and non-catalytic protein on the enzymatic hydrolysis has been extensively studied to increase the enzymatic hydrolysis of cellulose into fermentable sugars [7, 9 19]. The reported study showed that the non-ionic surfactant poly(oxyethylene)2o-sorbitan-monooleate (Tween 80) enhanced the enzymatic hydrolysis rate and extent of newspaper cellulose by 33 and 14%, respectively [20]. It was also found that 30% more FPU cellulase activity remained in solution, and about three times more recoverable FPU activity could be recycled with the presence of Tween 80. Tween 80 enhanced enzymatic hydrolysis yields for steam-exploded poplar wood by 20% in the simultaneous saccharification and fermentation (SSF) process [21]. Helle et al. [22] reported that hydrolysis yield increased by as much as a factor of 7, whereas enzyme adsorption on cellulose decreased because of the addition of Tween 80. With the presence of poly(oxyethylene)2o-sorbitan-monolaurate (Tween 20) and Tween 80, the conversions of cellulose and xylan in lime-pretreated com stover were increased by 42 and 40%, respectively [23]. Wu and Ju [24] showed that the addition of Tween 20 or Tween 80 to waste newsprint could increase cellulose conversion by about 50% with the saving of cellulase loading of 80%. With the addition of non-ionic, anionic, and cationic surfactants to the hydrolysis of cellulose (Avicel, tissue paper, and reclaimed paper), Ooshima et al. [25] subsequently found that Tween 20 was the most effective for the enhancement of cellulose conversion, and anionic surfactants did not have any effect on cellulose hydrolysis. With the addition of Tween 20 in the SSF process for... [Pg.354]

RAW MATERIAL Tween 80 Surfactant CHEMICAL DESCRIPTION Polyoxyethylene (20) sorbitan monooleate SOURCE ICI... [Pg.388]

The stereospeeifie Claisen transformation and the enantio-selective deearboxylation of ethylmalonic acid were found in the presence of cholesterylbenzoate and the formation of (S)-(-)-[Cr(ox)3] and (-)-helicene in photoreactions were reported on the (-)-rotating liquid-crystalline Tween-80, which is a polyoxyethylene-sorbitane-monooleate (n = 20)... [Pg.66]

The liquid gelators, Span 80-Tween 80 also forms emulsion organogels and emulsion hydrogels by fluid-filled fiber mechanism. It has been reported that Span 80 (sorbitan monooleate) and Tween 80 (polyoxyethylene sorbitan monooleate) mixed in the ratio of 1 2 w/w forms organogel with better firmness and architecture as compared to the other surfactant mixture ratios.When water is added dropwise into the homogenous surfactant mixture and oil, it forms spherical reverse-micellar droplets. These droplets/fibers self-assemble to form three-dimensional architecture to immobilize apolar solvent. " Similarly, in case of hydrogels micellar structures are formed, which entraps the external liquid phase to flow and form hydrogel. [Pg.1394]


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See also in sourсe #XX -- [ Pg.34 , Pg.130 ]




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