The first representative of cationic amphiphiles bearing three unsaturated moieties: Self-assembly and interaction with polypeptide

Novel cationic amphiphile bearing three allyl fragments (hexadecyltriallylammonium bromide, TAS-16) in the headgroup has been synthesized. Using the set of physico-chemical methods its self-assembly properties and functional activity of aggregates have been studied. It has been established, that aggregation behavior of TAS-16 is similar to the well-known analogue of trimethylammoinium series -cetyltrimethylammonium bromide (CTAB). In particular, critical micelle concentration for both amphiphiles in aqueous solutions equals 1 mM, hydrodynamic diameters of aggregates of TAS-16 and CTAB are 2-4 nm and its charge characteristics (zeta potential values) are in the range of 70-80 mV. However, practically useful properties of TAS-16 are more significant in comparison with CTAB: solubilizing capacity toward hydrophobic azodye of novel amphiphile is 1.5-fold higher, and its binding capability with bovine serum albumin (BSA) is higher. It has been revealed, that complexation of TAS-16 with BSA is contributed by electrostatic interactions, and the favorable binding site of polypeptide macromolecule is tryptophane amino acid residue. It has been shown, that substitution of methyl groups by allyl fragment in the head group structure of amphiphile leads to significant increase of membranotropic properties of surfactant.