Effect of Interlamellar Interactions on Shear Induced Multilamellar Vesicles Formation

Published

July 21, 2017

Author(s)

Youhei Kawabata, Robert David Bradbury, S. Kugizaki, Kathleen Weigandt, Y. B. Melnichenko, K. Sadakane, N. L. Yamada, H. Endo, Michihiro Nagao, H. Seto

Abstract

Shear-induced multilamellar vesicle (MLV) formation has been studied by means of small-angle neutron scattering (SANS) technique coupled with neutron spin echo (NSE) spectroscopy. A mass fraction of 10% of nonionic surfactant pentaethylene glycol dodecyl ether (C₁₂E₅) in water was selected as a model system for weak inter-lamellar interactions. The interaction is controlled by adding either anionic surfactant, sodium dodecyl sulfate (SDS), or antagonistic salt. Increasing the charge density in the bilayer induces an enhanced order of lamellar structure. Charge density dependence of the membrane bending modulus was determined by NSE, which showed an increasing trend with charge. This behavior is well explained by a classical theoretical model. Considering the Caille parameters calculated from the SANS data, the layer compressibility modulus B is estimated and the nature of the dominant inter-lamellar interaction is considered. Shear flow induced a formation of MLV around a shear rate of 10 s^-1, when a small amount of charge is included in the membrane. The flow-induced layer undulations are considered as being in-phase between neighboring layers when they inter-lamellar interaction is strong significantly. On the other hand, in the case of weak inter-lamellar interactions, the flow-induced undulations are not in-phase, resulting in an increase of the inter-lamellar gets larger and the steric interaction starts to make the undulations occur in-phase between neighboring membrane, which then resulted in the MLV formation.

Citation

Journal of Chemical Physics

Volume

147

Issue

3

Pub Type

Journals

Download Paper

Local Download

Keywords

surfactant, membrane, multilamellar vesicles, onion structure, rheology, dynamics, undulation, elasticity, neutron scattering

Citation

Kawabata, Y. , Bradbury, R. , Kugizaki, S. , Weigandt, K. , Melnichenko, Y. , Sadakane, K. , Yamada, N. , Endo, H. , Nagao, M. and Seto, H. (2017), Effect of Interlamellar Interactions on Shear Induced Multilamellar Vesicles Formation, Journal of Chemical Physics, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=923209 (Accessed April 25, 2024)