Complex of cationic micelles and anionic polyelectrolytes

Abstract

The adsorption of materials onto the surface of soft matter is of special interest in view of its relevance to biological system. It has been considered that electrostatic interaction and hydrophobic interaction play an important role in adsorption of materials and deformation of the surface of soft matter. 1. I have used small angle neutron scattering(SANS) to study the complex is dependent on the charge ratio, Z of cationic surfactant to polyelectrolyte. For 1/Z>0.5, the complexes is well-soluble in aqueous solution and have a necklace-like shape. The higher the polyelectrolyte concentration is, the shorter the length of a complex becomes. And, for 1/Z>12.5, complexes have spherical shape. The spherical form of micelle is maintained while the structure of complex is not. Ionic strength and conductance, however, increases with increasing the concentration of polyelectrolyte in solution. Here, the persistence length of polyelectrolyte is determined by the ionic strength, which is a key factor for bring together micelles. Moreover, the addition of simple salt induces to form a spherical complex at the concentration of polyelectrolyte formed necklace-like complex. Therefore, the persistence length of polyelectrolyte plays an important role in the complex shape-change. 2. I have perform the neutron and x-ray reflectivity for getting detail information about the structural change of lipid membranes by adsorption and penetration of MG and T-1249. the insertion of hydrophobic materials make the local order of hydrocarbon tails loose. And the fluidity of lipid membranes controls the insertion of materials.