Supramolecular Systems Based on Novel Amphiphiles and a Polymer: Aggregation and Selective Solubilization

Supramolecular systems based on novel triazole-containing and pyrimidine-containing amphiphiles bearing OH-groups and a hydrophilic polymer (polyethyleneimine, PEI) were fabricated. Aggregation threshold of individual amphiphile solutions and a surfactant/polymer binary mixture were determined to be equal to 2 and 0.05 mM, respectively, using tensiometry and conductometry techniques. It was found, that PEI addition to surfactant aqueous solutions induces the transition from open to closed association mode accompanying the decrease of mean hydrodynamic diameter of particles (D-H) from 100 nm to D-H <= 5 nm. Polymer addition to the system results in the leveling of pH decrease with surfactant concentration and increase of the electrokinetic potential values from 10 mV up to 40 mV. It was established that solubilization capacity of the supramolecular system formed could be increased by transition from surfactant individual solutions to the amphiphile/polymer binary system. The solubilization properties of the system strongly depend on the nature of the hydrophobic guest solubilized and differ by two orders of magnitude for hydrophobic azodye and lipophilic oxime.