Swelling limits for bilayer microstructures: the implosion of lamellar structure versus disordered lamellae

Swelling of charged bilayers can extend to well over 100 nm without loosing long range order. Attraction induced by solutes or screening induced by sa lt or buffers reduce the maximum periodicity. Microstructural evolutions ne ar the maximum swelling are reviewed as well as associated equations of sta te, i.e. osmotic pressures versus interlayer distances. We describe the dif ferent mechanisms which have been identified as limiting the swelling of a lamellar phase, and the phase equilibria involved when maximum swelling lim it is reached. (C) 2000 Elsevier Science Ltd. All rights reserved.