Mobility and reactivity in colloidal aggregates with motion restricted by polymerization

Abstract

Vesicle systems containing polystyrene or cross-linked polystyrene have been examined for the effect the presence of the polymer has on the physical properties of the vesicles, the lateral mobility of probe molecules in the plane of the bilayer and the diffusion of molecules across the bilayer. Differential scanning calorimetry of these vesicles, as well as vesicles containing monomer, and vesicles containing the polymer show the phase transition of hydrocarbon chains characteristic of a bilayer, to be present in all cases. Fluorescent probes show an increased lateral mobility when the monomer is introduced into the vesicle and a decreased lateral mobility when the vesicle contains the cross-linked polymer. Transbilayer movement of n.m.r. shift reagents is not markedly affected by the presence of polymer.