The formation and structure development of polyelectrolyte-surfactant complexes, PE-S, of double hydrophilic block copolymers poly(sodium 2-sulfamate-3-carboxylate isoprene)-block-poly(ethylene oxide), PSCI-PEO and cationic fluorosurfactant, N-(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluorodecyl)pyridinium chloride, HFDPCl, were studied by means of isothermal titration calorimetry, atomic force microscopy, cryogenic transmission electron microscopy and small-angle neutron scattering, in dilute aqueous solutions. Two samples of block copolymers differing in comonomer composition and polyisoprene block modification degree, PSCI171-PEO1261 and PSCI521-PEO612,1,2 were investigated and found to significantly influence the self-assembly process. In the case of PSCI171-PEO126, the gradual increase in the HFDPCl concentration first leads to the formation of spherical micellar complexes, which tend to aggregate into beds-on-string structures and finally into well-defined core-shell cylindrical nanoassemblies with the diameter of ~25nm and the length of up to several hundreds of nanometers. In the case of PSCI521-PEO612 at significantly lower PE to S molar ratio, well-defined vesicular structures with diameters ranging from 40 to 160 nm having membrane thickness of 5 nm are formed, while further addition of surfactant leads to the vesicles collapse and formation of sponge-like structures.With respect to the biocompatibility of both components of the studied coassembly, the prepared nanoparticles are prospective materials in nanomedicine as markers in 19F MRI.
References:
Štěpánek, M. Škvarla, J.; Uchman, M.; Procházka, K.; Angelov, B.; Kováčik, L.; Garamus, V. M.;
Mantzaridis, Ch.; Pispas, S. Soft Matter 2012, 8, 9412.Uchman, M.; Pispas, S. ; Kováčik, L.; Štěpánek, M. 2014 submitted.
Acknowledgment:
Authors acknowledge financial support from the Czech Science Foundation grant P208/12/P236
uchman@natur.cuni.cz
