title: Monolayer characteristics of a long-chain N,O-diacyl substituted ethanolamine at the air/water interface.
abstract: The N- and/or O-acylation of amphiphilic ethanolamine attracts particular attention because of its interesting biological, pharmaceutical, and medicinal properties. Tetradecanoic acid-2-[(1-oxotetradecyl)amino]ethyl ester (TAOAE) as the selected N,O-diacyl derivative of ethanolamine has been synthesized in order to obtain first information about its main interfacial characteristics, such as the surface pressure-area (π-A) isotherms, the morphology of the condensed phase domains, the lattice structure of the condensed phase, and information about the existence of interfacial hydrogen bonds (-NH···O═C-). The π-A isotherms of TAOAE, similar to those of the most usual monolayers of amphiphiles, show a sharp break point (A(c)) indicating the first-order phase transition from the fluid (liquid-expanded (LE), gaseous (G)) to the condensed (liquid-condensed (LC)) phase. On the mesoscopic scale, the dendritic domains homogeneously reflecting suggest an orientation of the alkyl chains perpendicular to the aqueous surface. The grazing incidence X-ray diffraction (GIXD) studies reveal hexagonal packing of the TAOAE molecules oriented perpendicular to the surface in an LS phase. The existence of a hydrogen-bonding network in the monolayer is supported by infrared reflection absorption spectroscopy (IRRAS) experiments.
authors: Max Planck Institute of Colloids and Interfaces, D-14424 Potsdam/Golm, Germany.
authors: G
authors: G
authors: Brezesinski
authors: B
authors: B
authors: Dobner
authors: C
authors: C
authors: Stefaniu
authors: D
authors: D
authors: Vollhardt
mesh_terms: D000388:Air; D004952:Esters; D019856:Ethanolamine / Q000737:chemistry*; D006860:Hydrogen Bonding; D019814:Myristic Acid / Q000737:chemistry; D009584:Nitrogen / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry*; D013055:Spectrophotometry, Infrared; D013499:Surface Properties; D014732:Vibration; D014867:Water / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D004952:Esters; D014867:Water; D019814:Myristic Acid; D019856:Ethanolamine; D009584:Nitrogen; D010100:Oxygen