Size determination of shear-induced multilamellar vesicles by Rheo-NMR spectroscopy

A model for analyzing the deuterium ((2)H) NMR line shapes of D(2)O ill surfactant multilamellar vesicle (MLV, "onion") systems is proposed. The assumption of the slow exchange of water molecules between adjacent layers implies that the (2)H NMR line shape is simply given by a SLIM of Lore...

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Detalhes bibliográficos
Autor principal: Medronho, B. (author)
Outros Autores: Schmidt, C. (author), Olsson, U. (author), Miguel, M. G. (author)
Formato: article
Idioma:eng
Publicado em: 2015
Texto completo:http://hdl.handle.net/10400.1/7271
País:Portugal
Oai:oai:sapientia.ualg.pt:10400.1/7271
Descrição
Resumo:A model for analyzing the deuterium ((2)H) NMR line shapes of D(2)O ill surfactant multilamellar vesicle (MLV, "onion") systems is proposed. The assumption of the slow exchange of water molecules between adjacent layers implies that the (2)H NMR line shape is simply given by a SLIM of Lorentzians if the condition of motional narrowing is also fulfilled. Using the classical two-step model for the NMR relaxation in structure fluids allows Lis to calculate how the NMR line shape depends oil the MLV size. The model is tested oil two different MLV systems for which the NMR line shapes are measured as a function of the applied shear rate using rheo-NMR. The MLV sizes obtained are in good agreement with previous data from rheo-small-angle light scattering.