Vesicles and particles of sodium bis(2-ethylhexyl) phosphate in binary and ternary systems

• Published in: Biochimica et biophysica acta Vol. 1074; no. 3; pp. 413 - 418
• Main Authors: Nakache, Evelyne, Bouloussa, Otman, Bourguet, Jacques, Lovera, Jacqueline, Gregiore, Pierre
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 06.08.1991; Elsevier
• Subjects: Artificial membranes and reconstituted systems; Binary system; Biological and medical sciences; DSC; Fundamental and applied biological sciences. Psychology; Interfacial tension; Membrane physicochemistry; Molecular biophysics; Nephelometry and Turbidimetry; Organophosphates - chemistry; Sodium bis(2-ethylhexyl) phosphate; Solutions; Solvents; Spectrum Analysis; Surface Tension; Surface-Active Agents; Swollen micelle; Ternary system; Transmission electron microscopy; Vesicle; Vesicle; Ternary system; Binary system; NaDEHP; Swollen micelle; CVC; Transmission electron microscopy; DSC; Interfacial tension; LC; LE; Sodium bis(2-ethylhexyl) phosphate; TEM; QELS; Aggregation; Water; Organic solvent; Ternary complex; Micelle; Surface pressure; Hydrophobicity; Phase transitions; Phosphorus Organic compounds
• ISSN: 0304-4165; 0006-3002; 1872-8006
• DOI: 10.1016/0304-4165(91)90093-V

Vesicles were identified in aqueous solution of pure sodium bis(2-ethylhexyl) phosphate, a short branched chain surfactant. Superficial tension measurements show that the vesicles appear above a molality of 0.02 (0.69 %w). These aggregates are equilibrium structures. The ‘packing parameter’ theory established by Israelachvili et al. allows the prediction of the occurrence of such vesicles. If an organic solvent, such as xylene or ethylhexanoate, is added to the binary system, a different type of aggregate appears, the size of which is determined by several methods including electron microscopy and light scattering. Interfacial tension measurements show that these aggregates would be expected to form above a molality of 0.02. According to our experimental results, the microstructure of these aggregates can be described as micelles and/or vesicles, swollen or not.