Gel thermoreversible

Less polysaccharide can also be used in products by taking advantage of the synergistic gelling of xanthan/galactomannan mixtures which forms thermoreversible gels at lower concentrations than if each is used separately. 

If the alkali step is removed a high acetyl gellan gum is produced. This type of gellan gum gives a more elastic thermoreversible gel similar to gelatine. This product might be more successful but it needs separate food approvals. 

Note 1 A thermoreversible gel is usually formed by cooling a polymer solution. In these cases, the gel temperature is a maximum temperature at which the presence of network is observed. 

Glycosyltransferases are also used extensively to modify natural polysaccharides. Thermoreversible gels that retrograded reversibly - comparable to gelatin... 

As barrier methods of protection are extremely effective at reducing the spread of STDs, researchers have been examining the possibility of new barrier products that women can use and thereby take control. To date the female condom has proved to be unpopular and has been described as both noisy and uncomfortable [121]. An alternative female condom is under development at the Universite Laval in Quebec, Canada, where researchers are currently in the process of developing a physical barrier in the form of an invisible condom. The invisible condom is a thermoreversible gel that hardens when inserted into the vagina or the rectum due to the increased temperature of the human body. The gel, which breaks down several hours after application, has been shown in laboratory studies to provide sufficient protection against herpes simplex virus (HSV) and HIV. Although the invisible condom will provide women with the autonomy to protect themselves, and it has the major disadvantage that is unlikely to go unnoticed by the user s partner. 

CGE separation of dsDNA was performed in a PDMS chip [183] and a PMMA chip [614], which used a sieving medium containing Pluronic (F127), a thermoreversible gel. 

Carbohydrate fat mimetics (Thayer, 1992) should be thermoreversible gels (e.g., starch) and microreticulated fibers (e.g., cellulose). As gels, they should provide plasticizing moisture, and as fibers, they should create structural rigidity. Concentrations higher than normal use levels are necessary for them to mimic the fatty sensation. They may be dry-blended with the rest of the formula, or suspended in water and sheared separately. 

Haineault, C., Gourde, P, Perron, S., Desormeaux, A., Piret, J., Omar, R. F., Tremblay, R. R., and Bergeron, M. G. (2003),Thermoreversible gel formulation containing sodium lauryl sulfate as a potential contraceptive device, Biol. Reprod., 69, 687-694. 

Arnauts, J. Berghmans, H., "Amorphous Thermoreversible Gels of Atactic Polystyrene," Polym. Comm., 28, 66 (1987). 

Films with low moisture resistmice obtmned after drying Thermoreversible gels produced from heated aqueous solutions gelation promoted by the presence of cations (potassium, calcium and sodium)... 

A different behavior is expected with thermoreversible gels. Using the LM pectin/calcium network as an example, the influence of temperature on SLR was... 

Low methoxyl pectins (< 50% esterified) form thermoreversible gels in the presence of calcium ions and at low pH (3 - 4.5) whereas high methoxyl pectins rapidly form thermally irreversible gels in the presence of sufficient (e.g., 65% by weight) sugars such as sucrose and at low pH (< 3.5) the lower the methoxyl content, the slower the set. 

Pectin Made of partly methoxylated 1,4-linked polygalacturonic acid At pH 3 pectin forms a thermoreversible gel. It is extracted from citrus peel Suspending agent, antidiarrheal formulations... 

Shalaby, S.W. Thermoreversible gels. In Water-Soluble Polymers, ACS Symp. Ser. American Chemical Society Washington, DC, 1991 467,Ch. 33. 

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