Lipophilic emulsifiers

Sorbitan oleate and the monolaurate are pale yeUow Hquids. Palmitates and stearates are light tan soHds. Sorbitan esters are not soluble in water but dissolve in a wide range of mineral and vegetable oils. They are lipophilic emulsifiers, solubiHzers, softeners, and fiber lubricants that find appHcation in synthetic fiber manufacture, textile processing, and cosmetic products. Sorbitan esters have been approved for human ingestion and are widely used as emulsifiers and solubiHzers in foods, beverages, and pharmaceuticals. 

Application Lipophilic emulsifiers, fiber lubricants and softeners. Insoluble in water, but soluble in oils and organic solvents. 

EMSORB Sorbitan Fatty Acid Esters are lipophilic emulsifiers and coupling agents serving as integral components of emulsif-iable Industrial mold release agents, textile fiber and yarn lubricants, and textile finishing softeners. They are widely used as surfactants and functional components in many kinds of Industrial and household products. 

A moderately lipophilic emulsifier and foam control agent, is useful as an emulsifier for polar and non-polar solvents, as spreading agent in pigment printing, and as a post-stabilizer in emulsion polymerization. An emulsifier in textile jet dye carrier applications. 

Is a moderately lipophilic emulsifier and lubricant. It is used as a co-emulsifier for metalworking oils and hydraulic fluids. In textiles it is used as a component in leveling and dispersing agents for vat and naphthol dyes, and as a co-emulsifier for rayon delusterants and fiber lubricants. HLB 8.6... 

A novel nanoparticulate lipid-based carrier system was developed by Mumper et al. at the University of Kentucky. ° This carrier system is composed of a lipophilic-emulsifying wax such as cetyl alcohol/ polysorbate 60 and other surfactants such as Brij 72, Brij 78, and Tween 80. The nanoparticles were formed through a warm microemulsion technique where encapsulates have included paclitaxel and plasmid DNA. The emulsification process is spontaneous, and cooling of the emulsion causes solidification of the nanoparticle-containing drug. This novel carrier has shown high efficiency in drug delivery across the blood-brain barrier. 

The selection of emulsifiers to prepare food emulsions is mainly based on their HLB number. This index is based on the relative percentage of hydrophilic to lipophilic groups within the emulsifier molecule. Lower HLB numbers indicate a more lipophilic emulsifier, while higher numbers indicate a more hydrophilic emulsifier. Emulsifiers showing HLB numbers between 3 and 6 are best for water-in-oil (W/O) emulsions, and emulsifiers with numbers between 8 and 18 are best for O/W emulsions. 

Mixed results were obtained when fatty acid esters of AA were applied to apple plugs as dispersions in pH 7 phosphate buffer, stabilized with lipophilic emulsifying agents such as Durkee s EC-25 or Durlac 100. The degree of inhibition was not... 

The emulsions so far described have been mainly of the simple 0/W type. However, because of their utility in other fields (e.g., cosmetology), an interest is developing in food applications of multiple emulsions, i.e., water-in-oil-in-water emulsions, since fliey modify the behavior of the fat and also offer the potential to carry, in their interior water droplets, materials of nutritional interest (172, 173). However, flic formulation and con trol of such preparations is much more difficult than for simple emulsions (174). The basic principles of such emulsion formulation are well known the water droplets within the oil droplet need to be stabilized using a mixture of lipophilic emulsifiers, whereas the stabilization of the oil droplets requires rather a hydrophilic surfactant. Evidently, the preparation of such emulsions cannot be preformed in a single stage, but requires the preparation of a W/O emulsion first, and then dispersion of this emulsion into an aqueous medium. 

It was, therefore, concluded that the internal polymeric emulsifier controls the release rates both by improving the film formation on the interface and by restricting the formation of reverse micelles in the oil phase. It is assumed that the presence of the two emul sifiers (Span 80 and silicone lipophilic emulsifier) form reverse hemimicelles. These structures are capable of solubilizing less water and, therefore, less marker, a fact that leads to slower release and the ability to con trol better the release rates. Emulsions prepared from polymeric emulsifiers and without the lipophilic monomeric emulsifier remained stable on the shelf for over 6 months and did not show any leaking of the marker upon storage. Once the monomeric emulsifier was added drop-... 

A lipophilic emulsifier (HLB about 4). Forms an L2 phase with water... 

Figure 7 presents thermograms of the solidification of water and the melting of ice in a simple W/O emulsion (emulsion 1) made of vaselin oil and lanolin (lipophilic emulsifier) as the continuous phase and deionized water as the dispersed phase. 

Figure 10 presents the cooling and heating thermograms of a W/OAV multiple emulsion. The internal phase is constituted of water dispersed in vaselin oil stabilized by lanolin as lipophilic emulsifier. This primary emulsion is then dispersed in water stabilized by sodium lauryl sulfate as hydrophilic surfactant. The droplets dispersed in the oil drops crystallize at -42°C, and the external water phase solidifies at - 17°C. There is no measurable delay in the melting of the solidified droplets. Hence, all droplets of both aqueous phases melt at the same temperature, around 0°C. The shape of the thermogram is similar to that of the melting of a pure compound mentioned in Section II. 

Terpolymers containing a cetyl group are also well suited for multiple emulsions, i.e., water-in-oil-in-water (w/o/w), because they do not migrate from one interface to the other [33]. They are adsorbed strongly at the interfaces due to their polymeric structure. In these systems, two interfaces have to be stabilized. One is between the inner oil phase and water phase, the other between the water phase and continuous oil phase. To prevent inhomegeneity and transformation into a two-phase system, terpolymers can thus be utilized. In contrast, at least two conventional emulsifiers with diflerent HLB values are required to stablize such emulsions one hyrophilic (HLB value > 15) and one lipophilic emulsifier [81]. 

Sorbitan monostearate is most often used in combination with the polysorbates in cakes, cake mixes, whipped toppings, cake icings, fillings, confectionery coatings, and coffee whiteners. Polyoxyethylene (20 EO) sorbitan monostearate 60 (Polysorbate 60) can be combined with lipophilic emulsifiers such as sorbitan... 

C.C. Chen, T.H. Tsai, Z.R. Huang, J.Y. Fang, Effects of lipophilic emulsifiers on the oral administration of lovastatin from nanostructured lipid carriers Physicochemical characterization and pharmacokinetics, Eur. J. Pharm. Biopharm. 74 (2010) 474-482. 

Uses Lipophilic emulsifier for preparations requiring abundant liquidity superfal-ting agent for hair care prods. 

Uses Lipophilic emulsifier for cosmetics Regulatory JSCI listed Projxrties Wh. solid HLB 8.0 Toxicology TSCA listed BS-20 [Nikko Chems. Co. Ltd]... 

Uses Lipophilic emulsifier for cosmetics gelling agent for hydrocarbons... 

Uses W/o emulsifier, lipophilic emulsifier Features Slable in lems with much water Properties Lt. yel. vise. liq. 

Uses 0/w lipophilic emulsifier for cosmetics, anticrystallizing agent Properties Wh. flake HLB 2.5 100% cone. 

Uses Lipophilic emulsifier, solubilizer, dispersant in food prods. 

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