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Le, Q.-C., Ropers, M.-H., Terrisse, H. & Humbert, B. (2014) Interactions between phospholipids and titanium dioxide particles. Colloid Surf. B-Biointerfaces, 123 150–157.
Added by: Laurent Cournède (2016-03-10 21:01:54) |
| Type de référence: Article DOI: 10.1016/j.colsurfb.2014.09.010 Numéro d'identification (ISBN etc.): 0927-7765 Clé BibTeX: Le2014 Voir tous les détails bibliographiques  |
Catégories: CESES Mots-clés: anatase, chain-length, ionic-strength, Langmuir film, lipid-bilayer, liposomes, membrane, nanoparticles, oxide, phosphate adsorption, Phospholipid, Pressure-area isotherm, Surface charge, tio2 surfaces, Titanium dioxide, Zeta potential Créateurs: Humbert, Le, Ropers, Terrisse Collection: Colloid Surf. B-Biointerfaces |
Consultations : 1/644
Indice de consultation : 4% Indice de popularité : 1% |
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A systematic study was carried out on monolayer films and lipid vesicles to elucidate the interactions between membrane lipids and commercial particles of titanium dioxide TiO2 (TiO2-P25). Pressure-area isotherms of lipids at various pH values were recorded on a Langmuir trough with or without TiO2-P25 and NaCl in the subphase. Electrophoretic mobilities of lipid vesicles and TiO2-P25 particles were measured to identify the pH range where attractive electrostatic interactions between lipids and TiO2-P25 could take place. The results show that (i) the surface of TiO2-P25 particles interacts only with some phospholipids, (ii) the driving forces are electrostatic and (iii) non-electrostatic interactions were also observed, depending on the molecular structure. More precisely, the phospholipids 1,2-dimyristoyl-sn-glycero-3-phosphate monosodium salt (DMPA), 1,2-dimyristoyl-sn-glycero-3-phospho-rac-1-glycerol (DMPG) and 1',3'-bis[1,2-dimyristoyl-sn-glycero-3-phospho]-sn-glycerol (TMCL) interacted strongly with the TiO2-P25 surface through electrostatic interactions, providing they were oppositely charged, i.e. for pH between 2 and 6.6. For TMCL and DMPG, interactions with the surface of TiO2-P25 in non-favourable electrostatic conditions, suggested another kind of binding, probably through the hydroxyl groups of the terminal glycerol. Weaker attractive interactions were demonstrated for 1,2-dimyristoyl-sn-glycero-3-phospho-L-serine (DMPS) and the synthetic lipid dihexadecyl phosphate (DHP). For DMPS, the carboxylate group is involved in the adsorption onto TiO2. The other membrane lipids such as 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC), 1,2-dimyristoyl-sn-glycero-3-phosphoethanolamine (DMPE) and sphingomyelin (SM) did not interact with TiO2-P25 regardless of pH. (C) 2014 Elsevier B.V. All rights reserved.
Added by: Laurent Cournède |