Molecular organizaton structural orientation and surface topography of monoacylated b cyclodextrins in monolayers at the air aqueous interface

RAQUEL VICO; O FERNANDO SILVA; RITA H DE ROSSI; BRUNO MAGGIO

AMER CHEMICAL SOC

Año: 2008 vol. 24 p. 7867 - 7867

he surface behavior of monoacylated -cyclodextrins, with hydrocarbon chains of 16, 14, and 10 carbons, has beenassessed by the measurement of the surface pressure, surface (dipole) potential, optical reflectivity, and surface topographyin monolayers at the air-water interface. For all the derivatives studied, the intermolecular organization adopted alongcompression-decompression isotherms reveals a rich variety of packing states which imply profound reorganization ofthe hydrophobic and hydrophilic moieties of the -cyclodextrin derivatives in the film, depending on the lateral surfacepressure. The intermolecular arrangements are consistent with the adoption of a different and defined orientation of the cyclicoligosaccharide unit, relative to the interfacial plane and the aqueous subphase. This is different from the behavior of theper-substituted derivatives, and none of the changes exhibited by the monosubstituted forms are consistent with the