Nanosized mixed aggregates of alkylated p-sulfonatocalix[n]arenes and cetyltrimethylammonium bromide: self-organization and catalytic activity

Self-organization and catalytic activity of supramolecular systems based on a series of O-alkylated p-sulfonatocalix[n] arenes (SCA: n = 4, 6, 8; R = Bu, Oct, Dod (Oct is octyl, Dod is dodecyl)) and cetyltrimethylammonium bromide (CTAB) were studied by dynamic light scattering, tensimetry, and spectrophotometry. In aqueous solutions containing SCA (10(-6)-10(-4) mol L-1) and CTAB (10(-2)-10(-12) mol L-1), mixed associates and SCA-CTAB micelles are formed in a wide concentration range. Their sizes (100-300 nm), properties, and reactivity depend mainly on the structure and concentration of the starting components, as well as on the nature of their associates in solutions. A relationship between the nonlinear concentration dependences of the sizes of SCA-CTAB micelles (SCA: n = 4, 6, 8; R = Dod) and their catalytic activity in the hydrolysis of O-ethyl O-(4-nitrophenyl) chloromethylphosphonate was established. The study of the physiological effect on plant cells in solutions of SCA (n = 6; R = Dod), CTAB, and their mixtures showed that SCA and CTAB exerted opposite effects on the energy exchange in the wheat root cells, while a mixed solution of these substances (1 : 1) has almost no effect on the physiological state of the roots, which is due to the formation of stable CTAB-SCA aggregates that protect the biosystem from the action of the starting components.