Sugar surfactants

The presence of long perfluoroalkyl chains gives sugars surfactant and emulsifier properties, with interesting applications in the biomedical field. These applications... 

V. Molinier, B. Fenet, J. Fitremann, A. Bouchu, and Y. Queneau, Concentration measurements of sucrose and sugar surfactants solutions by using the H NMR ERETIC method, Carbohydr. Res., 341 (2006) 1890-1895. 

Various auxiliaries with different functions are used in suspensions or dry syrups and instant granules for the preparation of suspensions. These include thickeners, hydrophilic polymers as dispersing agents, sugars, surfactants, electrolytes, colorants,etc. [296]. 

Ionic surfactants with only one alkyl chain are generally extremely hydrophilic so that strongly curved and thus almost empty micelles are formed in ternary water-oil-ionic surfactant mixtures. The addition of an electrolyte to these mixtures results in a decrease of the mean curvature of the amphiphilic film. However, this electrolyte addition does not suffice to drive the system through the phase inversion. Thus, a rather hydrophobic cosurfactant has to be added to invert the structure from oil-in-water to water-in-oil [7, 66]. In order to study these complex quinary mixtures of water/electrolyte (brine)-oil-ionic surfactant-non-ionic co-surfactant, brine is considered as one component. As was the case for the quaternary sugar surfactant microemulsions (see Fig. 1.9(a)) the phase behaviour of the pseudo-quaternary ionic system can now be represented in a phase tetrahedron if one keeps temperature and pressure constant. 

Figure 1.18 Mean curvature H of a non-ionic surfactant film at the water/oil interface as a function of temperature T (a) [26] and composition of the internal interface v,i (b) [90]. The decrease in H with increasing T is mainly due to the shrinking size of the head group, while the decrease in H with increasing v,i is due to the smaller head group area of the alcohol compared to the sugar surfactant. In order to illustrate this behaviour, a wedge-shaped representation has been chosen.

Stubenrauch, C. (2001) Sugar surfactants-aggregation, interfacial and adsorption phenomena. Curr. Opin. Coll. Interface Sci., 6, 160-170. 

The rate constants for a variety of micro emulsions based on a non-ionic surfactant and formulated with or without an alcohol as co-surfactant were determined from the slopes of the straight line obtained by plotting the reverse concentration of substrate against reaction time. The results are compiled in Table 5.1. It can be seen from the table that rather similar values were obtained for all the microemulsions based on an alcohol ethoxylate as surfactant. The reaction was more sluggish in the microemulsion based on the sugar surfactant octyl glucoside (CgGi). A probable reason for this difference was discussed... 

Hager, M., Currie, F. and Holmberg, K. (2004) A nucleophilic substitution reaction in microemulsions based on either an alcohol ethoxylate or a sugar surfactant. Colloids Surf. A, 250, 163-170. 

As described earlier, there are stringent regulations for the parenteral products and only few excipients are acceptable for parenteral delivery. The excipient selected for the parenteral delivery should be biocompatible, sterilisable, non-pyrogenic, non-irritant to nerves and non-haemolytic. Very few excipients fit into all these requirements. For example, the sugar surfactants are biocompatible and have fairly good solubilisation potential but they have been found to be haemolytic [111]. The excipients that are acceptable for parenteral delivery are as follows ... 

Kunieda, H., Rodriguez, C., Tanaka, Y., and Ishitobi, M. (2004) Effects of added nonionic surfactant and inorganic salt on the rheology of sugar surfactant and... 

Sato, T., Acharya, D.P., Kaneko, M., Aramaki, K., Singh, Y., Ishitobi, M., and Kunieda, H. (2006) Oil-induced structural change of wormlike micelles in sugar surfactant systems. /. 

The sugar surfactants of choice for industries such as agrochemicals and detergents are not the sucrose esters, which are often considered to be rather too expensive, but another set of sugar surfactants, the so-called alkyl glucosides... 

Human Erythrocyte Hemolysis Induced by Bioinspired Sugar Surfactants... 

Scheme 1 Structures and abbreviations of the investigated sugar surfactants a) Af-alkyl-W-methylaldonamides (C -MGA, Cn-MLA) b) N-alkanoyl-A-methylaldonamides (MEGA-n, MELA-n n = m + 1) c) A-dodecyl-A,A-bis[(3-D-aldonylamido)propyl]amines (C12-DGA, C12-DLA) d) Ai,Ai -bisdodecyl-A,A -bis[(3-aldonylamide)propyl]ethylenediamines (bis(Ci2-GA), bis(Ci2-LA))...

Claesson M, Kjellin URM (2006) Sugar surfactants in P. Soma-sundaran, A. Hubbard (Eds), Encyclopedia of Surface and Colloid Science, Taylor Francis, New York... 

Mkroemulsions Stabilized by Gemini, Dicephalic and Single-Head Single-Tail Sugar Surfactants as Biologically Important Systems Hemolytic Activity and Cytotoxic Studies... 

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