Electrostatic colloid-membrane binding

We investigate the adsorption of a charged spherical colloid on an oppositely charged flexible membrane. The long-ranged character of the electrostatic interaction leads to a re-entrant unwrapping of the membrane from the sphere: only for intermediate salt concentration and colloid sizes do we find full wrapping. We derive simple scaling relations for the wrapping transitions, which agree well with results obtained by numerically minimizing the free energy with respect to the membrane shape.