Many-body interactions between curvature-inducing membrane inclusions with arbitrary cross-sections.

By means of a multipolar expansion, we study analytically and numerically the interaction, in tensionless membranes, between multiple identical curvature-inducing membrane inclusions having arbitrary cross sections but uniform small detachment angles. In particular, for circular inclusions forming regular polygons, we obtain analytical expressions for the total asymptotic interaction, up to = 6, and we numerically compute the different multi-body contributions at arbitrary separations. We find that the latter are comparable to the sum of the two-body contributions.

Interaction and structuration of membrane-binding and membrane-excluding colloidal particles in lamellar phases.

Within the framework of a discrete Gaussian model, we present analytical results for the interaction induced by a lamellar phase between small embedded colloidal particles. We consider the two limits of particles strongly adherent to the adjacent membranes and of particles impenetrable to the membranes. Our approach takes into account the finite size of the colloidal particles, the discrete nature of the layers, and includes the Casimir-like effect of fluctuations, which is very important for dilute phases.

Coupling between Inclusions and Membranes at the Nanoscale.

The activity of cell membrane inclusions (such as ion channels) is influenced by the host lipid membrane, to which they are elastically coupled. This coupling concerns the hydrophobic thickness of the bilayer (imposed by the length of the channel, as per the hydrophobic matching principle) but also its slope at the boundary of the inclusion. However, this parameter has never been measured so far.

Capillary force and torque on spheroidal particles floating at a fluid interface beyond the superposition approximation.

By means of a perturbative scheme, we determine analytically the capillary energy of a spheroidal colloid floating on a deformed fluid interface in terms of the local curvature tensor of the background deformation. We validate our results, that hold for small ellipticity of the particle and small deformations of the surface, by an exact numerical calculation. As an application of our perturbative approach, we determine the asymptotic interaction, for large separations d, between two different spheroidal particles.

Capillary interaction of microspheres with pinned boundary conditions: a clarification.

It is the aim of this short note to point out that a quadratic contribution in the deviatoric curvature to the capillary interaction of microspheres with pinned contact lines is indeed compatible with the experimental measurements, in contrast to what has been reported in N. Sharifi-Mood, I. B.