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Polymeric aggregates (~100 nm) based on polydiacetylenic acid doped with the luminescent TbIII complexes with the tetra- and bis-1,3-diketonate derivatives of calix[4]arenes with nonyl substituents at the lower rims are considered as potential nanosensors. The obtained colloidally stable mixed aggregates can generate a substrate-induced luminescent response in aqueous solutions of 2,2´,6´,2´´-terpyridine in the micromolar concentration range due to the coordination of the latter by TbIII ions on the aggregate surface.

A composite for the extraction of lanthanide ions from strongly acidic media by temperature-induced phase separation was designed based on the nonionic surfactant Triton X-100 and new phosphine oxide derivatives. The dependence of the efficiency and selectivity of micellar extraction on the length of the hydrophobic substituent at the P=O group is determined by both the influence of hydrophobic substituents on the electron-donor capacity of the P=O group and the solubility of phosphine oxides in aqueous and micellar phases. The nitric acid concentration was found to influence the efficiency of extraction of lanthanide ions by phosphine oxides with different structures. An increase in the concentration of nitric acid in an aqueous medium from 0.1 to 1 mol L−1 leads to a decrease in the degree of extraction by water-soluble derivatives and a substantial increase in the degree of extraction by phosphine oxides, which are soluble only in the micellar phase of Triton X-100.

A procedure of micellar extraction of the lanthanide ions (La, Gd, and Lu) from nitric acid media based on the use of novel phosphine oxide derivatives is developed. In the micellar extraction, complexes of the lanthanide ions with the extractant in the ratio of 1 : 2 (metal : extractant) form. The dependence of the selectivity of extraction on the length of hydrophobic radicals attached to the P=O group was shown. The conditions of the selective micellar extraction in the series La > Gd > Lu with the use of an extractant containing octyl substituents at the P=O group were found.

Concentration range of solubilization of calix[4]resorcinarene (H8L) in sodium dodecyl sulfate (SDS) micelles was found. The interaction of the deprotonated form of H8L (tetraanions [H4L]4−) with tetramethylammonium (TMA) and choline cations in micellar solutions of SDS was studied by pH-metry and NMR spectroscopy. The concentration dependences of the change in the cloud point in a multicomponent system TMA (choline)-[H4L]4-SDS-tetrabutylammonium bromide were determined. A correlation of these dependences with host-guest binding processes was found. The sharp change in the cloud points of the corresponding micellar solutions in concentration regions of TMA (0-5·10−4 mol L−1) and choline (0–1.1· 10−3 mol L−1) is caused by the formation of inclusion complexes TMA (choline)-[H4L]4− at the interface of the aqueous and micellar pseudophases.

Solubilization of calix [4]resorcinarenes (Cn) with a varied length of hydrophobic substituents (R =Me, Pr, C5H11, C7H15, C9H19, and C11H23) in aqueous solutions of oxyethylated dodecanol Brij-35 was studied by the solubility method and 1D and 2D 1H NMR spectroscopy. The solubilization of Cn in micellar solutions of Brij-35 is caused by the formation of mixed Cn-Brij-35 aggregates and is weakened substantially with the elongation of R. It was shown by pH-metry and 1D 1H NMR spectroscopy that the receptor properties of the Cn anions toward the tetramethylammonium cations in the mixed aggregates differ substantially from those for the monomeric molecules in aqueous-organic and aqueous solutions. In particular, the binding of the tetramethylammonium cations does not result in screening of their N-Me fragments with the cyclophane cavity of the receptor.