SHAPE TRANSFORMATIONS IN THE LECITHIN BILE-SALT SYSTEM - FROM CYLINDERS TO VESICLES

In order to elucidate the still controversial structure and properties of mixed lecithin-bile salt micelles, we performed static and dynamic light scattering experiments over a wide range of scattering angles. The data were interpreted by applying concepts from polymer and colloi d physics and incorporating the effects of polydispersity and interpar ticle interactions. We demonstrate that a self-consistent interpretati on of the data at concentrations above the mixed micellar phase limit is possible in terms of a structural model of wormlike micelles. At co ncentrations below the micellar phase limit, mixed lecithin-bile salt vesicles form spontaneously and coexist with wormlike micelles in an e xtended coexistence region.