X-ray Diffraction Study of the Ordered Lyotropic Phases Formed by Sugar-Based Surfactants

Abstract

In this work we investigate lyotropic phases in different sugar-based surfactantlwater systems. Studies are carried out with the (N-alky1amino)-1-deoxylactitols (CS, C10, CIZ) and P-dodecyl maltoside. Liquid crystal phases are detected and lattice parameters determined by X-ray diffraction. The phases observed are the normal phases found in binary ionic or nonionic surfactantlwater systems. Schematic diagrams show the sequences of the lyotropic phases formed by these disaccharide surfactants. The difference in behavior is accounted for by the difference in chain length, hydrophilic ability, and steric hindrance of the polar head. IntroductionSurfactants derived from sugars form a large class of amphiphiles, which are currently receiving attention in view of their excellent biocompatibility and biodegradabi1ity.l Among the numerous applications of these compounds mention can be made of extraction and crystallization of membrane proteins2 and emulsification of substrates for enzymatic reaction^.^The first studies on the associative properties of these compounds were devoted to the solid-solid phase transitions and the liquid crystal properties of alkyl derivatives of carbohydrates in which the alkyl chain contained generally a t least eight carbon a t o m~.~-l~ Micellization of compounds of this family has been the subject of a few studies.13-15 More recently the surface properties of monolayers and the forces between bilayers of gangliosides

A Phase Diagram of theN-Cetylpiridinium Chloride/1-BuOH/Water Ternary System

“…The gregates in a hexagonal array. The L phase is in equilibrium phase appears to be composed of flexible bimolecular sheets with the hexagonal liquid crystalline phase at high surfactant of infinite area but arranged in parallel to each other (18). concentrations.…”

Lyotropic and thermotropic behavior of Alkylglucosides and related compounds

“…No efforts have been made to link the thermotropic and lyotropic properties, although these substances form micelles and lyotropic liquid crystals [5][6][7][8][9][10].…”

Thermodynamic properties of micellization of sodium dodecyl sulfate in binary mixtures of ethylene glycol with water

“…There has recently been much research dealing with the effects of nonaqueous polar solvents on the formation of cationic micelles (3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22). Micel!e or liquid crystal formation has been reported to occur in such solvents as hydrazine (3,4), glycerol (5,6), ethylene glycol (7,8), and formamide (9)(10)(11)(12)(13)(14)(15)(16)(17)(18), where all of the aforementioned solvents have high cohesive energy, dielectric constant, and a high degree of hydrogen bonding. Evans and co-workers (19) have indicated that the ability of a solvent to form hydrogen bonds is a necessary condition of micelle formation.…”