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Updated: Mar 23, 2026

Assembly and Characterization of Polyelectrolyte Complex Micelles
Published on: March 2, 2020
Effect of Polyelectrolyte Stiffness and Solution pH on the Nanostructure of Complexes Formed by Cationic Amphiphiles
Maor Ram-On1, Yachin Cohen1, Yeshayahu Talmon1
1Department of Chemical Engineering and The Russell Berrie Nanotechnology Institute (RBNI), Technion - Israel Institute of Technology , Haifa 3200003, Israel.
Abstract:
The interaction between amphiphiles and polyelectrolytes has been widely investigated in recent years due to their potential application in industry and medicine, with special focus on gene therapy. The cationic lipid dioleoyl trimethylammonium propane, DOTAP, and the oppositely charged polyelectrolytes, sodium poly(acrylic acid) and sodium poly(styrenesulfonate), form multilamellar complexes in water. Because of the different molecular stiffness of the two polyelectrolytes, they form different nanostructured complexes. Also, because of the different ionization behavior of the two polyelectrolytes, pH differently affects the complexation of the polyelectrolytes with didodecyldimethylammonium bromide (DDAB), another cationic surfactant. We used cryogenic temperature transmission electron microscopy (cryo-TEM) and small-angle X-ray scattering (SAXS) to compare the nanostructures formed. Our results show that although the basic nanostructures of the complexes are always lamellar (multilamellar or unilamellar) the morphology of the complexes is affected by the polyelectrolyte rigidity and the solution pH.
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