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arXiv · 1910.05165

Magnetic tubules

Damien Letellier·Olivier Sandre·Christine Ménager·Valérie Cabuil·Michel Lavergne
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Abstract

Dispersion of tubules made of diacetylenic phospholipids (DC 8,9 PC), in aqueous colloidal dispersions of magnetic nanoparticles is studied as a function of the sign of particles surface charges. In every case the tubule-vesicle transition temperature is decreased by the presence of the magnetic nanoparticles. Electrophoresis experiments on the tubules in pure water permits to conclude on a negative apparent surface charge. We study the magnetic response of the system to a static or stationary rotating field and to a magnetic field gradient. These experiments reveal an excess or a lack of magnetic permeability between tubules and the surrounding medium. Electron microscopy confirms these results showing an electrostatic interaction between the phospholipidic bilayer and the magnetic particles.

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Damien Letellier, Olivier Sandre, Christine Ménager, Valérie Cabuil, Michel Lavergne. 2019-10-11. Magnetic tubules. https://doi.org/10.1016/s0928-4931(97)00035-0

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