INTERFACIAL RELAXATION OF PHOSPHOLIPID LAYERS AT A LIQUID-LIQUID INTERFACE

The phospholipid, L-alpha-dipalmitoylphosphatidylcholine (DPPC), forms a monomolecular film onto a pendent drop by adsorption at the water-c hloroform interface. Transient relaxations of the adsorption layer aft er an area change of the drop surface induced by a definite drop volum e increase are studied by axisymmetric drop shape analysis (ADSA). The dynamic interfacial tension response to small-amplitude disturbances of the adsorption equilibrium are recorded and interpreted in terms of a diffusion controlled relaxation theory. The experiments provide inf ormation on the interfacial dilational elasticity of the phospholipid layer at the water-chloroform interface. (C) 1998 Elsevier Science S.A . All rights reserved.