Alkyl Chain Ordering of Asymmetric Phosphatidylcholines Adsorbed at a Liquid-Liquid Interface
نویسندگان
چکیده
Vibrational spectroscopic investigations of hydrocarbon chain ordering in phosphatidylcholines (PCs) adsorbed from aqueous solution to a carbon tetrachloride-water interface presented here examine on a molecular level the organization pertinent to the surface characteristics displayed by these films. In a series of saturated symmetric and asymmetric chain PCs, both symmetric PCs with 16 or fewer carbons per acyl chain and highly asymmetric PCs produced relatively disordered films at the liquid-liquid interface. The longest chain PCs studied, 1,2-distearoyl-sn-glycero-3-PC (C18/C18), 1-stearoyl-2-palmitoyl-sn-glycero-3-PC (C18/C16) and 1-palmitoyl-2-stearoyl-sn-glycero-3-PC (C16/C18), formed well-ordered layers at room temperature. The results can be explained in terms of enhanced chain-chain interactions among the longer, nearly symmetric hydrocarbon chains. Properties of the neat liquid-liquid interface that may influence the formation of these well-ordered two-dimensional phases are discussed.
منابع مشابه
Molecular Structure and Ordering of Phospholipids at a Liquid-Liquid Interface
Vibrational sum frequency spectroscopy in conjunctionwith interfacial pressuremeasurements provides direct information about the molecular structure of phosphocholine monolayers adsorbed to the interface between D2O and carbon tetrachloride. Monolayers form from breakup at the interface of aqueous phase phosphocholine vesicles. For the saturated, symmetric, dialkylphosphocholines used in this s...
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