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New biodegradable water/sodium bis(2-ethylhexyl) sulfosuccinate (AOT)/isopropyl myristate (IPM) microemulsion systems for the delivery of medicinal and physiologically active substances are synthesized. The optimum concentrations of components that ensure solubilization of the largest amount of water-soluble substances are selected. The diffusion of model substances (L-lysine, L-serine, glycine, β-alanine) across a membrane is studied. It is found that the rate and pattern of release from the microemulsion vary strongly, depending on the terminal functional groups of amino acids. The effect the hydrophobicity and size of the introduced compounds have on the interaction with components of the transport system is determined using H1 NMR, self-diffusion NMR, the polarized luminescence of laurdan and fluorescein probes, and dynamic light scattering. It is shown that short-chain and polar amino acids are released much more quickly than charged amino acids. The results allow determination of the delivery characteristics of more complex counterparts (e.g., medicinal substances and protein molecules).

The optical and photocatalytic properties of CdS quantum dots doped with manganese ions are considered. The quantum dots were synthesized by the colloidal method in an aqueous medium with mercaptoacetic acid as stabilizer. The optical, dimensional, and paramagnetic properties of the obtained nanoparticles were studied. The photocatalytic properties of the quantum dots were studied in the model degradation of rhodamine B. The effect of the concentration of manganese ions and the temperature of the reaction mixture on the rate of photodegradation of the dye was studied.

Based on the luminescence spectroscopy data, it was shown that the method of fixing (between two plates of quartz, quartz and brass, quartz and silicon) a vitrified film prepared from a powder of an anisometric europium(III) β-diketonate complex does not affect the photophysical properties of the film in the temperature range of 270–370 K and, accordingly, does not affect the operational characteristics of a reusable and highly sensitive luminescent temperature probe based on it.

Optical and magnetic properties of CdS quantum dots (QDs) doped with europium(II) and gadolinium(III) ions were studied. l-Cysteine stabilized nanoparticles were synthesized by the colloidal method in aqueous media. The QDs obtained have a hexagonal crystal lattice. The nanoparticle size varies from 3 to 14 nm. The EPR spectra of nanoparticles prepared in different conditions were measured and analyzed. Dependences of the optical properties of nanoparticles on the reaction time and pH values were studied. The dependence of the luminescence properties of CdS QDs on the dopant ion type was established. It was shown that the increase in the reaction time and medium pH values favors a bathochromic shift of maxima in the luminescence spectra of nanoparticles.

A new approach to the synthesis of luminescent soft media using a terbium β-diketonate complex and substituted p-tert-butylthiacalix[4]arene containing quaternary ammonium fragments with amino acid substituents in the lower rim was developed. The synthesized heteroligand complex was incorporated into the framework of the lyotropic mesophase P123-C2H6O2. The liquid crystal properties of the P123-C2H6O2 binary system were studied and the concentration limits of the complex incorporation into the lyomesophase were determined. The long-period ordered structures of lyomesophases was confirmed by small-angle X-ray scattering measurements. The intermolecular interactions of the system components were estimated by IR spectroscopy. The luminescent properties of lyomesophases including a hetero-ligand macrocyclic complex and a low-molecular-weight analog based on an ionic liquid were analyzed. Enhanced luminescence efficiency was observed for lyomesophases with the macrocyclic complex.

The process of phase formation in solutions of polyacrylic acid and cetyltrimethylammonium bromide was studied in microfluidic channels with a characteristic size of 100–200 µm. The system of convection—diffusion—reaction equations was solved to develop an association model in polyelectrolyte—surfactant solutions in a microchannel with the laminar flow of the reactants. The phase formation conditions in the microchannel volume were considered. The recommendations for control of the phase behavior in the microchannel were proposed, as well as for the design and operation mode of microfluidic devices used for the synthesis of polymer—surfactant complexes and characterization of association in polyelectrolyte—surfactant solutions.

Modified polysaccharides were prepared by the reaction of citrus pectin with a cationic monomer, (1,2-epoxypropyl)triethylammonium chloride, in alkaline medium and under the action of microwave radiation in the reactor system microwave–ultrasonic–UV-induced synthesis. Organic hybrids were prepared by mixing aqueous solutions of natural polysaccharides (pectin and modified pectin with chitosan) under ambient conditions in 1 : 1 ratio. The influence of the concentration of citrus pectin, its modified samples, chitosan, and their organic hybrids on the flocculating properties was studied for a model disperse system, a suspension of titanium dioxide in water and aqueous salt solutions, under the conditions of free (unrestricted) sedimentation. The influence of the ionic strength on the conformational state of polysaccharide macromolecules and on the aggregation of titanium dioxide particles was analyzed.

A new approach to the creation of photostable highly sensitive sensor elements for reusable luminescent thermometers based on vitrified films of mesogenic europium(III) and terbium(III) beta-diketonate complexes that are oxygen insensitive, effectively absorbing light in the region of 390–410 nm and reversibly changing the luminescence decay time in the region of 143–348 K, is proposed.

Arelevant task in the technology of cosmetic and pharmaceutical substances is that of protecting the skin from the harmful influences of ultraviolet light - sunburn, photodermatoses, skin cancerogenesis, and light-induced aging. Gels containing N-(β-hydroxyethyl)-4,6-dimethyldihydropyrimidone-2 (xymedone) and amphiphilic components, i.e., nonionic surface-active substances (surfactants), were developed and studied. Aspectrophotometric method was used to study the selective absorption of xymedone in the UV range. Overall, the structural- mechanical characteristics of gels and assessment of the effects of surfactant on xymedone release processes were used to select the optimum composition for effective protection against light by gels. Studies in models of ultraviolet erythema in albino guinea pigs and volunteers receiving prophylactic applications showed that xymedone-containing gel had photoprotective effects. The presence of a hydroxyethylated higher fatty alcohol in the gel composition with xymedone increased its photoprotective activity.

Novel prospective transport systems are prepared that consist of lyotropic liquid crystals (LLCs), water/sodium bis(2-ethylhexyl)sulfosuccinate (AOT)/isopropyl myristate. The temperature boundaries of phase transitions at different water contents and in the presence of guest molecule L-lysine amino acid and the types of mesophases formed are determined via differential scanning calorimetry (DSC), polarization optical microscopy (POM), and measurements of the wetting angle. It is shown that upon a reduction in the H2O content and the introduction of L-lysine, the thermal stability of a system and the temperature of a phase transition increase, while the mass loss upon heating is diminished. The concentration dependences of thermodynamic properties allow us to control the phase transition temperatures that determine the processes of the controlled release of bioactive molecules from the studied LLC-system.

Experiments on recording the ultrafast optical Kerr effect (OKE) in solution of europium(III) β‑diketonate complexes in toluene at a concentration of 10–2 mol/L showed that the total OKE signal is not a superposition of two contributions, one of which is related to the vibrational–rotational dynamics of toluene molecules, while the other is due to the vibrational–rotational dynamics of the europium(III) complexes. This immediately indicates that the europium(III) complexes essentially change the structure of liquid toluene, which is reflected in the character of an orientational response in picosecond range.

An 18-fold increase in the mean luminescence intensity of Tb3+ ions in a vitrified film of a terbium( III) β-diketonate complex under UV laser radiation in atmospheric oxygen at 300 K was observed. Luminescence and Raman spectroscopy data reveal that the observed effect was caused by photophysical and photochemical processes changing the geometry and structure of the complex.

Isotropic melts of nine metallomesogenic complexes with a smectic-А phase have been studied by the electric birefringence method. Complexes include Dy, Tb, Gd, and Er rare-earth ions, Schiff bases as ligands, and alkyl sulfate or nitric-acid counterions. It has been shown for the first time that both the magnitude and the sign of the electro-optical effect in the isotropic phase for the studied substances are determined by the length of counterions. This means that the dielectric anisotropy of smectic lanthanide complexes can vary widely depending on counterions: it can be positive, negative, or close to zero.

Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 0172—0175, January, 2018.

A TDDFT study of energy transfer processes in luminescence composite materials based on mesogenic europium (III) complexes with substituted β-diketones and Lewis bases and some semiconducting polymers is presented. The calculated energies of the lowest singlet and triplet excited states of ligands and polymers were used to construct the energy level diagrams and indentify the main channels of intramolecular energy transfer. A system of a complex and a polymer, which is most preferable for practical application in optoelectronics, was selected. The simulated data agree well with the experiment.

Phase diagram was obtained for the first time and processes of lecithin self-organization in the water/ propylene glycol/lecithin/Vaseline oil system were examined. Tensiometric data were used to find the optimal composition of the components, necessary for providing the stability of this system. Specific features of the microemulsion–liquid crystal structural-phase transition were examined. It was shown that both the packing type of molecules and the type of distribution of dispersed-phase particles change in this transition. The systems under study are promising for delivery of medicinal and biologically active substances into cells.

Modified polysaccharide was synthesized by the reaction of amylopectin with a cationic monomer, (1,2-epoxyprop-3-yl)triethylammonium chloride, in alkaline solution in the presence of Fenton’s reagent. The influence of the concentrations of amylopectin, gelatin, their polymer-inorganic hybrids, and modified pectin on their flocculating properties in free (unrestricted) sedimentation of ocher suspension as a model disperse system was studied. Amylopectin exerts a stabilizing effect, whereas the modified pectin and polymer-inorganic hybrid exert a flocculating effect. The influence of the mode of introducing polymer additives on the flocculating effect and aggregation of ocher particles was analyzed.

The permittivity components of the liquid crystalline gadolinium complex with Lewis bases and β-diketonates as ligands are measured in the frequency range from 100 Hz to 5 MHz. The magnitude and sign of the dielectric anisotropy of the complex are determined. Two dispersion regions of the permittivities are found in the liquid crystalline phase. The mechanisms responsible for the relaxation phenomena occurring in the sample are established. The dielectric relaxation times, activation energies, and dipole moment of the complex are obtained. The results of the study are compared with the dielectric properties of ytterbium and terbium complexes having the same ligand environment.

The adhesive interaction of some polymer surfaces with neutral, acidic, and basic samples formed on a cantilever specimen has been evaluated via atomic-force microscopy. The thermodynamic work of adhesion has been calculated using the Johnson–Kendall–Roberts model. The differences in the work of adhesion values obtained in the interaction of acidic, basic, and neutral samples with the same polymer surface have been found. The experimentally obtained values of work of adhesion have been carefully compared with theoretically calculated ones, which allowed the conclusion to be drawn that the area of research under consideration is promising.

Measurements of the refractive indices and optical anisotropy of a series of liquid crystalline coordination compounds based on lanthanides with an identical ligand environment have been carried out. It was found that the magnitude of the optical anisotropy of the investigated complexes was several times smaller than the anisotropy of organic liquid crystals. Analysis of the results showed that the variation of the ion complexing agent had little effect on the magnitude of the optical anisotropy in the mesogenic complexes containing the same ligands. The even-odd alternation of the optical anisotropy of lanthanidomesogens at the increasing the number of protons in the ions of the lanthanides has been observed.

Atomic force microscopy (AFM) has been used to study forces of intermolecular interactions in two different types of liquid crystal (LC) systems (thermotropic and lanthanide-containing lyotropic ones) with different supramolecular organization and degrees of surface hydrophilization in relation to self-associated silane monolayers on a cantilever probe. Statistical analysis has been applied to the force curves to determine adhesion between liquid crystals and monoassociated layers of trichlorododecylsilane and (3-mercaptopropyl)trimethoxysilane on silicon. The results have been analyzed within the framework of hydrophilic and hydrophobic interactions and compared to the free surface energy values calculated by the Owens, Wendt, Rabel and Kaelble method. Lanthanide-containing liquid crystals demonstrate high value of adhesion work to monoassociated silane monolayers due to their considerable free surface energy. The method of chemical force microscopy (CFM) is found to be applicable to the direct determination of the adhesion force of liquid crystals.

The components of the dielectric constant of a terbium-based liquid-crystalline complex have been measured in the frequency range of 350–5 × 106 Hz. The magnitude and sign of the dielectric anisotropy of the complex have been determined. Dispersion of the dielectric constants in the liquid-crystalline and isotropic phases has been found. The mechanisms responsible for the relaxation phenomena that appear in the studied sample have been determined. The time of dielectric relaxation, the activation energy, and the dipole moment of the complex have been obtained.

The complexing of protonated chitosan with dodecyl sulfate ions in water solutions is studied using IR spectroscopy data and quantum-chemical calculations. It is established that the electrostatic interaction between the protonated amino groups of chitosan and dodecyl sulfate ions is apparent in the IR spectrum as a band at 833 cm−1. The need to consider the effect the solvent has on the formation of hydrogen-bound ion pairs [CTS+ ⋅ C12H25O3-] is shown via a quantum-chemical simulation of the equilibrium geometry and the energy characteristics of complexing and hydration.

The values of optical anisotropy of two series of thermotropic nematic liquid crystalline complexes based on the ions Eu+3, Gd+3, Tb+3, and Dy+3 have been determined. Even–odd alternation of optical anisotropy with an increasing number of protons in ions of lanthanides has been observed. It is established that, in the considered series of lanthanidomesogens, optical anisotropy is more sensitive to changes in the ligand structure of complexes than to the variation of the complexing agent.

Hybrid liquid crystal systems with different ratios of the components have been prepared on the basis of 5,5′-di(heptadecyl)-2,2′-bipyridine tris(β-diketonate) lanthanum(III), europium(III), and terbium(III) complexes, and their liquid crystalline and luminescence properties have been studied. A relation has been found between the luminescence intensity and concentration of the components, and a probable mechanism of photoexcitation in the hybrid systems has been proposed.

This paper provides the results of POM, DSC and XRPD methods characterizing the liquid crystalline behaviour, thermal properties and structural parameters of lyotropic systems based on a nonionic surfactant and lanthanum nitrate (La(3+)). The systems based on tetraethylene glycol monododecyl ether (C12EO4) and lanthanum nitrate have been demonstrated to form a lamellar phase. The concentration and temperature ranges of the existence of mesophases as well as thermodynamic parameters of phase transitions have been estimated. The structural parameters of the lamellar phase of the C12EO4/La(3+)/water systems have been determined using X-ray diffraction. The model of molecular packing in lamellar lanthanide-containing lyotropic mesophases was proposed for the observed patterns of structural parameters obtained at various water contents. NMR (1)H with a pulsed magnetic field gradient has been used to characterize molecular motions in the C12EO4/La(3+)/H2O systems with different water contents.

The processes of dispersing carbon nanotubes in interfacial and adhesive compositions for producing modified polymer aramid papers in the presence of nonionic surfactants—ethylene oxide derivatives-have been studied. Optimum surfactant concentrations for the more effective disintegration of carbon nanotubes have been found. Quality-control methods of the distribution of the nanomodifiers in the composite surface layer have been developed. Prepreg samples with the improved physical and mechanical properties for application in aviation have been prepared.

Phase behavior of emulsion liquid-crystal systems constituted by tetraethylene glycol monododecyl ether, water, and Vaseline oil was studied by a set of methods. The type of the mesophase and the temperature range of its existence were determined. It is shown that the wetting method is applicable to identification of phase transitions in the given lyotropic liquid-crystal emulsion systems.

The sign and the magnitude of the dielectric anisotropy of an ytterbium-based paramagnetic nematic liquid crystal complex, namely, tris[1-(4-(4-propylcyclohexyl)phenyl)octane-1,3-dione]-[5,5'-di(heptadecile)-2,2'-bipyridine]ytterbium, are determined. The temperature dependence of the permittivity components of the complex is obtained in the temperature range of a nematic phase. The sign of the anisotropy of the magnetic susceptibility of this compound is experimentally determined.

Luminescent properties of liquid-crystalline tris(β-diketonate) europium(III) complexes with Lewis bases (substituted 2,2′-bipyridine and 1,10-phenantroline) are investigated. Absolute and relative quantum yields and lifetimes are determined. Absorption, excitation, and emission spectra of the complexes are investigated.

The kinetics of free and hindered sedimentation of a suspension of titanium dioxide (anatase) under the action of a high-molecular-weight cationic acrylamide copolymer and of hybrid polymer-inorganic nanosystems was studied. The influence of the content of the cationic acrylamide copolymer in hybrid systems and of the particle size on the TiO2 aggregation in gravity and centrifugal force fields was analyzed.

Dispersion of C60 fullerenes in water and ethanol in the presence of nonionic surfactants, ethylene oxide derivatives, was studied. It was found that the quality of the dispersion process and the stability of dispersions depend on the structure, degree of oxyethylation, and concentration of surfactants. The optimal conditions are found in which stable fullerene dispersions are obtained as ingredients of cosmetic preparations with antioxidant properties.

Possibility of using the electron paramagnetic resonance method to study the antioxidant activity of structured colloid systems with active components: polymeric cosmetic gels, foaming detergents (shampoos), and lotions. It is shown that this versatile method opens up new opportunities for determination of the antioxidant activity not only in liquid-phase systems, but also in gels without any considerable disintegration of their structure. The antioxidant activity is affected by the concentration of additives, nature of an extract, and composition of formulation ingredients.

The most common technique used in pulse electron paramagnetic resonance spectroscopy to determine interspin distances in the nanometer range is pulse electron double resonance, while relaxation-induced dipolar modulation enhancement (RIDME) is a promising alternative to this method. In this article we introduced a selective hole-burning technique for RIDME experiment, which allows dead-time free measurement of dipolar modulation without the use of the second microwave frequency or a magnetic field jump. This technique was tested on a short, stable biradical in a frozen solution, and the optimal experimental conditions for the measurement of dipolar modulation were found. Interspin distances in the range of 13 A ≤ r ≤ 25 A can be measured by the proposed method.

The review concerns liquid-crystalline mono- and disubstituted ferrocenes, systems based on ferrocenophane, heteronuclear complexes with ferrocene-containing ligands, ferrocene-based polymers and dendrimers, as well as mixed systems based on ferrocene derivatives. It is shown that liquid-crystalline ferrocene exhibits unique physical properties. The state of the art in the title field and prospects for the development of research on such liquid crystals are outlined and the present and possible fields of their application are discussed. The bibliography includes 131 references.

The techniques of injecting nanomodifiers into the sulphamate electrolyte used for electrolytic forming of nickel antiabrasive protective tipping are considered. The optimal concentration of surfactant and nanomodifier are determined. The graphs are also presented.