English   español  
Por favor, use este identificador para citar o enlazar a este item: http://hdl.handle.net/10261/16162
Compartir / Impacto:
Estadísticas
Add this article to your Mendeley library MendeleyBASE
Citado 10 veces en Web of Knowledge®  |  Pub MebCentral Ver citas en PubMed Central  |  Ver citas en Google académico
Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Título

The effect of molecular shape on the thermotropic liquid crystal behavior of monolauroylated amino acid glyceride conjugates

AutorMorán, María del Carmen; Pinazo Gassol, Aurora; Clapés Saborit, Pere; Infante, María Rosa; Pons Pons, Ramón
Palabras clavePolarized Light Microscopy
MCG Method
Liquid Crystal
Monoacylglycerol amino acid
Surfactants
Fecha de publicación5-nov-2005
EditorAmerican Chemical Society
CitaciónJournal of Physical Chemistry B 109(48): 22899–22908 (2005)
ResumenMonoacylglycerol amino acid conjugates constitute a novel class of specific biocompatible surfactants that can be considered analogues to partial glycerides and lysophospholipids. They consist of one aliphatic chain and one polar head, i.e., the amino acid, linked through a glycerol moiety. In a previous work, we synthesized monolauroylated amino acid glyceride conjugates, 1-O-lauroyl-rac-glycero-3-O-(Nα-acetyl-l-amino acid), changing the amino acid headgroup systematically: arginine (compound 2), aspartic acid (compound 3), glutamic acid (compound 4), asparagine (compound 5), glutamine (compound 6), and tyrosine (compound 7), to elucidate the structure−properties relationship governing the occurrence of their polymorphism. The thermotropism of the new compounds was measured with polarizing light microscopy, differential scanning calorimetry, and X-ray diffraction and compared with the classical monoglyceride rac-1-lauroylglycerol (compound 1). The experiments were performed for a sequence of heating, cooling, and reheating scans. The results showed that compounds 1−6 exhibit a thermotropic smectic phase. As a consequence, the substitution of the polar head did not engender any curvature into the system, which might lead to the formation of cubic or columnar phases. Interestingly, liquid crystalline phases were not found in the case of compound 7. Small-angle X-ray diffraction data in the gel phase revealed that the substitution of the polar head by the different amino acid structures did not modify significantly the lamellar repeat distance relative to that of the reference one. The observed area per molecule, however, was larger for the new compounds. Consequently, interdigitation was promoted in compounds 2−7. The diffraction patterns were analyzed in terms of electron density profiles, using a modified Caillé theory plus a Gaussian electron density representation (MCG method) on X-ray diffraction data.
Descripción10 pages, 6 figures, 5 tables.-- PMID: 16853983 [PubMed].-- Printed version published Nov 8, 2005.
Versión del editorhttp://dx.doi.org/10.1021/jp053093l
URIhttp://hdl.handle.net/10261/16162
DOI10.1021/jp053093l
ISSN1520-6106 (Print)
1520-5207 (Online)
Aparece en las colecciones: (IQAC) Artículos
Ficheros en este ítem:
No hay ficheros asociados a este ítem.
Mostrar el registro completo
 



NOTA: Los ítems de Digital.CSIC están protegidos por copyright, con todos los derechos reservados, a menos que se indique lo contrario.