System tricaprylin

Hyde et al. (24) found that the peak apparent viscosity of lamellar liquid crystal fell by about two orders of magnitude as alcohol chain length was reduced from 15 to five in water-alcohol-Teepol systems. However, the complete picture of how various types of amphiphilic compounds and their mixtures influence viscosity is not available. In particular, it is not known under what conditions fairly low viscosities of liquid crystals can be achieved although Hallstrom and Friberg (22) report viscosities of about 0.2 poise for some compositions in the water— monocaprylin-tricaprylin system. As indicated previously, low viscosities increase the possibilities for occurrence of hydrodynamic instabilities involving cellular convection. 

The typical reverse hexagonal LLC composed of GMO/tricaprylin and water (Typ), and fluid hexagonal systems containing either 2.75 wt% Transcutol or ethanol (Tra and Eth, respectively) as a fourth component, were further explored as solubihzation reservoirs for several bioactive molecules with different polarities [29, 52]. 

Fig. 12.11 Schematic illustration of the interactions between the components, representing the second and third Hn systems (water/glycerol-filled Hu phases, in the absence and presence of PC, respectively) at three temperatures a 25, b 60, and c 70 °C. For simplification PC and tricaprylin are not shown in the image...

Fig. 12.12 The release profile of DNA from the two columnar Hn mesophases considered release from the nonionic system (filled circles, GMO/tricaprylin/water/ascorbic acid) and release from the cationic-based columnar hexagonal phase (open circles, GMO/oleyl amine/tricapiylin/ water/ascorbic acid) at room temperature...

The zwitterionic surfactant phosphatidylcholine (PC) was used for the study of enzymatic hydrolysis reactions in microemulsions [80-82], The oil used in all the investigated systems was tricaprylin (TC). 

Lintomen L, Pinto RTP, Batista E, Meirelles AJA, Maeiel MRD (2001) Liquid Iiquid equilibrium of the water + citric acid + short chain alcohol + tricaprylin system at 298.15 K. J Chem Eng Data 46 546-550... 

The effect of alcohol on the distribution of (total) water between the free and bound states was exemplified [2,9] by the swelling of a fixed amount of a 1 1 (by weight) C,2(EO)8-water mixture with increasing amounts of a 1 1 (wt/wt) solution of pentanol + dodecane. The relative amount of (total) water constantly diminished upon the addition of pentanol + dodecane, but when the alcohol concentration reached a threshold value, some of the (boimd) water became free (Fig. 11). The same phenomenon was observed in the system phosphatidylcholine (25 wt%)-tricaprylin + alcohol (60 wt% molar ratio of 1 5, respectively)-water (15 wt%). The alcohols used were ethanol, butanol, and hexanol, and the free water content increased in that order [72], The same inverse dependence on the alcohol hydrophiUcity was observed for sucrose ester-based microemulsions [29]. It seems that alcohol molecules adsorbed at the interface distort the three-dimensional network of... 

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