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Purpose of the study. To study the features of the local distribution of populations of immune system cells in patients with non-invasive muscular bladder cancer of various degrees of malignancy.Materials and methods. The study included 51 patients with newly diagnosed non-muscle-invasive bladder cancer (papillary urothelial carcinoma) who received complex treatment and follow-up after 9 months at the oncourological department of the National Medical Research Center of Oncology. Patients were divided into two groups: group 1 – with a tumor of low malignant potential (Low grade – LG), n = 31; group 2 – with a tumor of high malignant potential (High grade – HG), n = 20. After 6–9 months, 24 patients were diagnosed with a relapse of the disease – in 48,4 % in patients of group 1 (n = 15) and in 45 % – in group 2 (n = 9). In cell suspensions obtained from the primary and recurrent tumors, as well as the perifocal zone, the relative number of populations of immunocompetent cells was estimated using flow cytometry. A comparison was made of the content of individual populations of lymphocytes in the tumor tissue, the perifocal zone of primary and recurrent lesions of various degrees of malignancy. Statistical processing was performed using Statistica 13.0.Results. The development of a recurrent tumor of low malignant potential is accompanied by the involvement of cells of innate immunity (NK- and NKT-lymphocytes) into its microenvironment, which is associated with an imbalance in the number of main cells of adaptive immunity – a fairly pronounced decrease in the tumor of T-lymphocytes of the helper-inductor type was noted with a constant content cytotoxic T-lymphocytes, as well as the multidirectional nature of changes in DP- (decrease) and DN-lymphocytes (increase). A feature of the development of a recurrent tumor of high malignant potential is that it is accompanied by the involvement of innate immunity cells (NK- and NKT-lymphocytes) into its microenvironment, as well as multidirectional changes in DP- (decrease) and DN-lymphocytes (increase).Conclusion. Studies of the population composition of tumors and their perifocal tissues of NMIBC revealed a number of features that are reflected in the redistribution of cytolytic cells, the formation of immunosuppressive conditions, which are reflected both in the manifestation of the biological properties of tumor cells and in changes in the cellular composition of bladder tissues involved in the process. development and progression of cancer.

This review article is devoted to the main problems of early diagnostic and prognosis of non-muscle-invasive bladder cancer, which accounts for 75 % of all newly detected cases of bladder cancer according to statistics. Chromosomal disorders that have been detected in urothelial cells can lead to the development of non-muscle-invasive bladder cancer. The review highlights the main problems of existing diagnostic systems for bladder cancer, their disadvantage and limitations of use in practice. Special attention is given to tumor stem cells, which are actively involved in the development of relapses of malignant neoplasms, and, also play an important role in the development of chemo - and radioresistance of tumor cells. Their significance in the diagnosis, detection of disease recurrence and the possibility of using the data obtained to adjustment therapeutic methods of treatment in oncology is one of the main tasks in cancer pathology.

The encapsulation of medicinal substances in various polymers is a common way to increase their thermal, hydrolytic, and chemical stability. However, the bioavailability of the encapsulated drugs decreases. The solution to this important problem can be the preparation of nanocapsules of medicinal substances using complexing agents, for example, cyclodextrins. The purpose of this work is to study the possibility of encapsulation of benzoic, salicylic, and β-resorcylic acids using α- and β-cyclodextrins. The interaction of benzene carboxylic acids with cyclodextrins in aqueous solutions at 20–30 оС has been studied by spectrophotometry. The formation of complexes with a composition of 1:1 in the cyclodextrin – benzene carboxylic acid systems has been proven. The stability constants of the complexes and the main thermodynamic parameters of complex formation have been calculated. It has been shown that the nature of changes in the spectral characteristics of benzene carboxylic acids in the presence of cyclodextrins can be used to predict the possibility of aromatic organic compounds encapsulation. The determining role of the complementarity of geometric parameters of cyclodextrins and benzene carboxylic acids in the preparation of inclusion complexes with features of nanocapsules has been found. The prospects of using β-cyclodextrin for encapsulation of benzene carboxylic acids have been demonstrated. The complexes of β-cyclodextrin with benzene carboxylic acids were synthesized and studied by IR spectroscopy, X-ray analysis and derivatography. The formation of two types of complexes in the β-cyclodextrin – benzene carboxylic acid system was established. The first type of complexes is formed due to nonspecific interactions between the hydrophobic cavity of β-cyclodextrin and the benzene carboxylic acid molecule, the second type is due to specific interactions between the functional groups of molecules. Benzoic and salicylic acids form nanocapsules with β-cyclodextrin, and their hydrolytic and thermal stability increases. Complexes of the second type acquire the properties of a new compound: β-resorcylic acid loses its individuality, forming strong supramolecular structures with β-cyclodextrin.

The aim of this work is to study the influence of the chemical nature of grafted β-cyclodextrins side functional groups on chemically modified silica gels sorption affinity for cadmium, lead, and copper cations as the most typical water pollutants. Two organo-inorganic sorbents that differ only in the chemical nature of side functional groups of grafted β-cyclodextrin molecules wide edge were synthesized by chemical immobilization of mono-(6-O-(toluenesulfonyl))-β-cyclodextrins on the granular mesoporous silica gel surface. The obtained functionalized silica gels were characterized by IR and UV spectroscopy, chemical, elemental and derivatographic analysis, pH-metry, low-temperature nitrogen adsorption-desorption as well as sorption measurements. The results of studying the sorption of cadmium, lead, and copper cations from nitrate buffer solutions with pH = 2.0 were analyzed using the Lagergren kinetic model for pseudo-first and pseudo-second order processes, and the equilibrium sorption results were analyzed using the Langmuir and Freindlich models for homogeneous and heterogeneous surfaces. It has been found that only β-cyclodextrin-containing surface centers of chemically modified silica gels participate in the sorption of metal cations. The simultaneous formation of inclusion complexes of grafted β-cyclodextrin molecules with nitrate anions of the solution and mixed complexes of metal cations with side functional groups of the wide edge of immobilized cyclic oligosaccharides occurs during the interaction of synthesized silica gels with buffer solutions of cadmium, lead and copper nitrates. The sorption affinity of β-cyclodextrin-containing silica gel with secondary alcohol groups in the structure increases in the order Cd 2+

Subclinical hypothyroidism is common in general practice. The clinical significance of latent thyroid dysfunction has not yet been determined. The parameters of lipid metabolism and oxidative stress were studied in patients suffering from subclinical hypothyroidism between the ages of 18 and 50 years. They had a level of thyroid stimulating hormone ≥4 mIU/l, the level of free thyroxine was normal. The control group consisted of healthy individuals with thyroid-stimulating hormone level of 0,4-2,4 mIU/l. Thyroid status, thyroid peroxidase antibodies, lipid profile, malondialdehyde-modified low-density oxidized lipoproteins, antibodies to low-density oxidized lipoproteins, homocysteine were determined for all individuals. With the repeated determination of thyroid-stimulating hormone in 16,8% patients spontaneous recovery of thyroid-stimulating blood hormone level was observed, which was associated with lower values of thyroid-stimulating hormone and the absence of thyroid peroxidase antibodies. In the group of patients with thyroid stimulating hormone levels ≥7 mIU/l, the total cholesterol level was significantly (p=0,02) higher than in the control group. In patients with elevated values of malondialdehyde-modified oxidized low-density lipoprotein, thyroid stimulating hormone level of ≥7 mIU/l was more frequently detected. A negative correlation was found between the level of IgG antibodies to low-density oxidized lipoproteins and the concentration of free thyroxin. In the control group, the correlation was found between the concentration of IgG antibodies to low-density oxidized lipoproteins and the level of thyroid-stimulating hormone. In the group of subclinical hypothyroidism, the concentration of homocysteine was significantly (p=0,01) higher in men. In patients with subclinical hypothyroidism, more often hyperhomocysteinemia was detected compared with the control group. The results suggest that subclinical hypothyroidism is associated with initial changes in the metabolism of lipids and homocysteine.

Templated sol-gel synthesis of MCM-41‑type mesoporous silicas was realized in the presence of azo dyes (alizarin yellow and methyl red) as co-templates and silanes obtained on their basis as structure-forming components. It has been found from the results of low-temperature adsorption-desorption of nitrogen that using of azo dyes and dye-containing silanes in sol-gel synthesis leads to the substantial increase of surface area and total pore volume, and decrease of pore diameter of obtained mesoporous organosilicas. The X-ray diffraction analysis proved formation of hexagonally arranged structure of mesopores in synthesized organosilicas. It has been demonstrated due to visualization of mesoporous structure by transmission electron microscopy that all synthesized materials have hexagonally arranged structure of cylindrical pores, entrances to which are oriented outside of particles that provide accessibility of functional groups for sorbate molecules. Obtained organosilicas of MCM-41 type were used in study of dyes sorption from diluted phosphate buffer solutions as dependent on their equilibrium concentration, pH of medium, and duration of contact. It has been found that the most efficient sorption of alizarin yellow takes place at рН ~ 3 and methyl red at рН = 2.5-5.0. Analysis of kinetic curves carried out using Lagergren, Ho‑McKey, and Weber-Morris models has shown that process of azo dyes sorption by organosilicas is described by kinetic model of pseudo‑second order. The parameters of equilibrium sorption of alizarin yellow and methyl red on organosilicas of MCM‑41 type were calculated using Langmuir, Freundlich, Redlich‑Peterson, and Brunauer‑Emmett‑Teller models. Sorption of a number of acid dyes from their individual solutions was studied at pH 4.8. It has been found that chemical immobilization of methyl red on silica surface causes increase of acid dyes sorption. The contribution of cooperative interactions, which arise between the aromatic groups of azo dyes immobilized in surface layer of silica and dye molecules in a solution, in the process of their sorption was confirmed. Modification of silica surface with capable to self-aggregation dyes is a promising way in chemical design of sorption-active materials.

Increased thyroid stimulating hormone (TSH) levels are detected quite often especially in older patients. Increased TSH level doesn't usually indicate the formation of persistent hypothyroidism and may be due to concomitant somatic disorders. Determining the threshold values of TSH associated with cardiovascular diseases (CVD) is an important clinical task. Aim. To study the detectability of subclinical hypothyroidism, the range of thyroid-stimulating hormone values associated with CVD in patients who seek medical care at the multidisciplinary hospital of the North-West region. Material and methods . 1340 patients of different sex and age with normal TSH value (0.4-2.5 mlU/l) and subclinical hypothyroidism were included into the study. Subclinical hypothyroidism was considered an increase in TSH level >4.0 mlU/L, provided that the level of free T4 is normal. According to electronic case histories in all patients, CVD (hypertension, coronary heart disease, heart failure, arterial atherosclerosis of the lower extremities) and a history of cardiovascular events (unstable angina, acute myocardial infarction, stroke and transient ischemic attack) were analyzed. For data processing the program Statistica, version 1 2 was used. Results. The detectability of subclinical hypothyroidism was 1 0.2%, manifest hypothyroidism - 2.4%. In patients with subclinical hypothyroidism, CVD were detected significantly more often than in patients with euthyroidism (p

It is known that patients with chronic kidney disease (CKD) often have hypothyroidism. In patients with CKD, iodine excretion in the urine is disrupted. The high content of iodine in the thyroid gland and tissues leads to a disruption in the synthesis and peripheral metabolism of thyroid hormones. In hypothyroidism, there is a disruption of sodium and water reabsorption in the proximal tubule, the volume of the filtrate increases, the volume of the tubular apparatus overloads, and the eGFR decreases.THЕAIM:to study the occurrence of hypothyroidism in patients with different stages of CKD, to evaluate the parameters of thyroid status and antithyroid antibodies in patients with CKD.PATIENTS AND METHODS.953 patients from I.P. Pavlov SPbSMU clinics (screening group) were examined. TSH, free T4, serum creatinine were defined and eGFR was calculated using the formula CKD-EPI in all patients. A group of patients with hypothyroidism accounted for 466 patients. Patients with a normal TSH of 0.4-2.5 mIU / L (comparison group) were selected from the screening group.RESULTS.eGFR in the screening group and in the group of hypothyroid patients correlated with age. Hypothyroidism was associated with female sex and older age. In the group of patients with advanced stage CKD (3B-5), the incidence of subclinical and manifest hypothyroidism was 3 times higher than in the group with normal GFR (GFR> 90 ml / min, p = 0.007). In the group of patients with hypothyroidism, the frequency of advanced stages of CKD (3B-5) was 2 times higher than in the comparison group (p = 0.02). In patients with CKD, a direct correlation was found between GFR and free T3 (r = 0.34, p = 0.02). Thyroid peroxidase antibodies were revealed in 64% of patients with CKD with hypothyroidism.CONCLUSION.Hypothyroidism is associated with chronic kidney disease. For patients with CKD, there is a syndrome of euthyroid pathology ("low T3" syndrome). Hypothyroidism in patients with CKD is not always the outcome of autoimmune thyroiditis.

Synthesis of mesoporous silicas of MCM-41 type with chemically immobilized β cyclodextrin-containing groups was realized by template sol-gel method in the presence of functional silane. The influence of reaction mixture composition used at β cyclodextrin-silane synthesis (molar ratio β cyclodextrin:3 aminopropyltriethoxysilane: 1,1'-carbonyldiimidazole) on chemical structure and arrangement of mesopores of resulting organosilica materials was proved. The enhancement of ethoxysilyl constituent in β cyclodextrin-silane used in sol-gel condensation leads to the formation of silicas with higher content of chemically immobilizedβ cyclodextrin-containing groups and less arranged mesopores. Structure of obtained materials was determined using chemical analysis, infrared spectroscopy, low-temperature nitrogen adsorption-desorption, X-ray diffraction, and transmission electron microscopy. With the aim to elucidate the contribution of β cyclodextrin-containing groups in the removal of azo dyes, sorption of methyl red and alizarin yellow on synthesized silicas was studied from phosphate buffer solutions in dependence of contact duration, equilibrium concentration, and pH of medium. The results were analyzed using Langmuir, Freundlich and Redlich-Peterson equations. It has been found that equilibrium sorption of methyl red and alizarin yellow on parent silica and silica with chemically immobilized β cyclodextrin containing groups is described by the Redlich-Peterson model.

It was found with the help of spectrophotometry, IR spectroscopy, X-ray phase analysis, and thermogravimetry, that new supramolecular structures in the β-cyclodextrin–β-resorcylic acid system are generated as a result of a spontaneous exothermic process. It was proven that the inclusion complexes of the host–guest type with a 1:1 ratio between β-cyclodextrin and the molecular form of β-resorcylic acid (or its monovalent anion) are formed through van der Waals interactions of the aromatic ring of β-resorcylic acid with the inner hydrophobic cavity of β-cyclodextrin. It was shown that partial displacement of water molecules from the inner cavity of the cyclic oligosaccharide and complete immersion of β-resorcylic acid molecule inside it occur in this case; thermal stability of β-resorcylic acid increases.

Doxorubicin belongs to the most widely used anticancer chemotherapy drugs. Yet the long‑term treatment with doxorubicin is associated with toxic side effects. Minimization of undesired damages of healthy cells without reducing therapeutic action of doxorubicin can be attained using drug carrier systems, particularly silica nanoparticles. The aim of this work was elucidation of the probable mechanism of interaction between doxorubicin and silica surface. The adsorption of antitumor drug on mesoporous silica nanoparticles of MCM-41-type was studied depending on the contact time, pH of phosphate buffer solution, and doxorubicin concentration by use of UV-Vis spectroscopy. Experimental kinetic curves of adsorption were compared with theoretical models of Lagergren and Ho-McKay for pseudo-first and pseudo-second order processes. High correlation coefficients indicate that the kinetics of drug adsorption on silica surface at pH 5.0 and 7.0 can be fitted by pseudo-second order kinetic model. Equilibrium adsorption of doxorubicin was analyzed by Langmuir, Freundlich, Redlich‑Peterson, and Brunauer‑Emmet‑Teller isotherm models. BET model is the most appropriate for prediction of doxorubicin equilibrium adsorption on MCM-41 silica from solutions with pH 7.0, whereas drug adsorption at pH 5.0 can be described by Freundlich model. The results obtained for doxorubicin adsorption kinetics and equilibrium on MCM-41 surface can be useful for comparative analysis of chemically modified silicas effectiveness.

Aromatic compounds are organic contaminants in aqueous streams of various industries. Even at low concentration, benzene and its derivatives are toxic agents. Silicas are promising materials for benzene and phenol adsorption from water mixtures due to their unique physical and chemical properties. In this research, we realized sol-gel synthesis of β-cyclodextrin-MCM 41 silica using β-cyclodextrin-containing silane and tetraethyl orthosilicate as silica sources in the presence of ionic template (cetyltrimethylammonium bromide). β-Cyclodextrin-silane was prepared by modification of (3 aminopropyl)triethoxysilane with oligosaccharide activated by N,N'-carbonyldiimidazole. The successful incorporation of β-cyclodextrin moieties in silica is verified by means of FT-IR spectroscopy and quantitative chemical analysis. Obtained β-cyclodextrin-MCM 41 silica was characterized by X-ray diffraction, transmission electron microscopy, and low-temperature adsorption-desorption of nitrogen. On the basis of analysis, β-cyclodextrin-MCM 41 silica is well-ordered mesoporous material with high surface area (about 800 m 2 g –1 ) and sufficient oligosaccharide group loading (up to 0.022 µmol m –2 ). Adsorption of benzene and phenol from aqueous solutions on β-cyclodextrin-MCM 41 silica was studied as the function of time and equilibrium concentration. Greater specificity of aromatic compounds adsorption for β-cyclodextrin-MCM-41 silica in comparison with MCM-41 was demonstrated. Moreover, the higher adsorption performance of β cyclodextrin MCM 41 silica towards benzene and their adsorptive affinity to phenol can be useful in the separation of aromatic compounds. The proposed synthesis approach may be applicable for obtaining of ordered β-cyclodextrin-containing functional materials with high affinity to aromatic compounds of suitable geometry for water treatment.

The influence of β-cyclodextrin on the solubility, protolytic properties, and complex formation behavior of 2-aminodiphenylamine was studied using UV spectroscopy. In accordance with the results of the spectrophotometric titration that was carried out in phosphate buffer solutions, the presence of β-cyclodextrin does not change the value of the deprotonation constant of the primary amino group of 2-aminodiphenylamine. This fact confirms that the primary amino group is not involved in the complex formation and interaction between β-cyclodextrin and 2-aminodiphenylamine occurs via the phenylimine moiety. The phase solubility profiles of 2-aminodiphenylamine in the presence of β-cyclodextin, at pH = 1.00 and pH = 5.00, indicate formation of inclusion complexes with limited solubility and can be classified as Higuchi–Connors curves of BI and BS type, respectively. The stoichiometry of the complexes and the apparent stability constants that characterize the β-cyclodextrin complexes with both protonated and neutral forms of 2-aminodiphenylamine were estimated from the dependence of absorbance intensity of the guest molecule at increasing amounts of β-cyclodextrin by the Ketelar equation. The linearity of the plots in the coordinates of the Ketelar equation proves the formation of 1:1 inclusion complexes for both protolytic forms of 2-aminodiphenylamine. It was found that inclusion complex formation is preferable for the neutral form of 2-aminodiphenylamine.

The prevalence of subclinical hypothyroidism (SH) is large and according to various studies is from 3 to 21%. In the Russian Federation to date, there are no major epidemiological studies assessing the functional state of the thyroid gland. It seems relevant to study the TSH level in patients who turned to the clinical units of a large hospital in the North-West region to determine the prevalence of thyroid dysfunction in patients of different sex and age. 5,303 patients were examined, who applied to the I.P. Pavlov SPbSMU clinics for 2017. In all patients the level of TSH and free T4 was determined. SH was considered to increase the level of TSH more than 4.0 mIU/l at a normal level of free T4. Patients were divided into groups by age and TSH level in accordance with existing recommendations. Among the examined patients were 29.26% of men and 70.73% of women. The mean age was 55.08 ± 17.07 years. The TSH level had an abnormal distribution and averaged 2.77 mIU/l (TSH median 1.73 mIU/l). In women the level of TSH was significantly higher in all studied groups of patients (p = 0.0001). Among women, significant differences in the level of TSH between the elderly and young patients (p = 0.015) were found. The incidence of SH in the total group of patients was 10.1%. In the men surveyed, the incidence of SH was 7.3%, and in the female group - 11.3%. In the elderly patients, the incidence of subclinical hypothyroidism in women was 2 times higher than that of men. In most cases (77.4%) in patients with SH, the TSH level was in the range of 4.0-6.9 mIU / L. The clinical significance of minimal thyroid insufficiency requires further study.

Selectively modified silica materials with uniform hexagonally ordered cylindrical mesopores were synthesized by combination of sol‑gel condensation and postsynthetic chemical modification. Hexagonally arranged porous structure of silica carriers was confirmed by X-ray diffraction and low‑temperature ad‑desorption of nitrogen. Content of functional groups immobilized onto external surface of silica particles was determined from chemical analysis of surface reaction products. Release capability of MCM‑41 mesoporous silicas selectively modified with N‑(2‑aminoethyl)‑3‑aminopropyl or N‑[N’-(N’-phenyl)-2-aminophenyl]‑3‑aminopropyl groups was studied by use of para‑aminobenzoic acid as model biologically active substance. It has been found that desorption of aromatic amino acid from mesoporous channels of silica can be regulated using pH-sensitive functional groups which are chemically bounded with outer silica surface.

Nanoporous b-cyclodextrin-containing silicas which differ in functional substituents of wide edge of attached cyclic oligosaccharide molecules (alcohol, bromoacetyl, thiosemicarbazidoacetyl groups) were synthesized. Сhemical composition of surface layer of organosilicas and their sorptional parameters were determined using IR spectroscopy, isotherms of nitrogen ad-desorption, elemental, chemical and thermogravimetric analyses. Ranges of thermal and chemical stability of synthesized b-cyclodextrin-containing silicas were defined; a method of organosilicas regeneration was proposed. Activation energies of water removal from the inner cavities of β-cyclodextrins and from the surface of functional organosilicas were calculated. Distribution and selectivity coefficients for sorption of mercury(II), copper(II), lead(II), cadmium(II), and zinc(II) cations were computed.

The paper has investigated the impact of hardness salts modeling soft and hard waters on sorption of trace amounts of Cd(II) by β-cyclodextrin-containing silicas, which differ by chemical nature of sorption centers. The paper has demonstrated high affinity of organosilicas to Cd(II) in its sorption from multicomponent solutions. Equilibrium sorption of cations from aqueous nitrate solutions within a broad interval of concentrations has been described by means of the Langmuir and Freundlich models and was interpreted in terms of the theory of hard and soft acids and Pearson bases.

The chemical immobilization of β-cyclodextrin and its bromoacetyl and thiosemicarbazidoacetyl functional derivatives on the surface of highly disperse amorphous nanoporous silica was performed. β-Cyclodextrin-containing silicas were found to have high affinity to mercury(II), cadmium(II), and zinc(II) cations. Supramolecular surface structures formed whose chemical composition depends on the nature of the sorbed cations and the functional substituents in the attached β-cyclodextrin molecules.

This paper discusses application of gas and liquid chromatography to studies of surface chemistry and various materials. Examples of studying adsorption processes from gas and liquid media with application of the chromatography technique are given. It is shown that the information on the structure of the material obtained using the chromatography technique allows predicting the regularities of chromatographic retention for molecules of different structures and various sorbents. The chromatography technique is frequently used in studies of nanomaterials and stable nanoparticles. It is shown that the chemical properties of surfaces modified by nanoparticles can be advantageously used in gas and liquid chromatography techniques. Much attention is given to molecular statistical calculations of adsorption on carbon sorbents in gas and liquid chromatography. The possibilities of the technique regarding prediction of retention of various sorbates and specification of structural parameters of molecules are demonstrated. Methodological and preparative aspects of a new area, micellar chromatography of nanoparticles, are considered. Options of liquid chromatography for separation, including preparative separation, identification, and classification, are shown.

The thermodynamic characteristics of adsorption on original and modified silica and ultradispersed diamond adsorbents are determined using gas chromatography. The contributions of the dispersion and specific donor-acceptor interactions to the total adsorption energy are estimated and the relation between the properties of the modified specimens and the surface treatment is found. Based on the data obtained, donor and acceptor characteristics of the adsorbent surfaces studied are estimated.

Liquid chromatography, which makes it possible to investigate interphase processes, is an additional method for studying inverse micellar systems without changing their properties in the process of sample preparation. In the case of using these systems to synthesize nanoparticles (NPs), it becomes possible to determine their adsorption characteristics, to investigate the processes of modifying surface adsorbents by NPs, to determine their sizes, and to divide them into fractions according to their sizes and surface properties of the micelles. The method is simple and rapid and permits one to use standard, relatively inexpensive equipment and can be applied in many physicochemical studies of NPs synthesized in micellar solutions.

Complex formation of β-cyclodextrin with para-aminosalicylic acid in buffer solutions is studied by UV spectroscopy. It is found that the stoichiometric proportion of the components in the β-cyclodextrin–para-aminosalicylic acid inclusion complex is 1:1. The Ketelar equation is used to calculate the stability constants of the inclusion complexes at different temperatures. The thermodynamic parameters of the complex formation process (ΔG, ΔH, ΔS) are calculated using the van’t Hoff equation. The 1:1 β-cyclodextrin–para-aminosalicylic acid inclusion complex is prepared in solid form and its characteristics are determined by IR spectroscopic and x-ray diffraction techniques.

In the present work, the study on detonation nanodiamond (DND) powders modifications in gaseous media was carried out. The surface properties of DND were studied by TGA, IR-spectroscopy, pH-potentiometry and chromatography methods. It was determined that modifying the DND surface reduces specific retention volumes and retention times of adsorbates. At the same time, specific and dispersion interactions have decreased. Such phenomena are significant for gas chromatographic separation of complex mixtures. The study of DND in contact with water and water solutions showed that chemical modification of DND produces on its surface oxygen-containing groups with acidic character. The latter stipulates its ion-exchange properties and applicability to liquid chromatography. In summary, the performed research provides significant perspective toward new-generation adsorbent creation with controlled surface identification for gaseous and liquid chromatography purposes.

UV spectroscopy was used to study the protolytic properties and determine the ionization constants of p-aminobenzoic acid in the presence of β-cyclodextrin. Formation of supramolecular structures of 1: 1 composition was established. Stability constants of the β-cyclodextrin-p-aminobenzoic acid inclusion complex were calculated, as were the thermodynamic parameters (ΔG°, ΔH°, and ΔS°) of its formation. The complexing process between β-cyclodextrin and p-aminobenzoic acid was found to occur spontaneously in the temperature range under investigation while being accompanied by energy liberation and leading to a reduction in the system’s entropy.

The construction of adsorption sites for mercury(II) by chemical immobilization of β-cyclodextrin and its functional derivatives on a surface of macroporous amorphous silica is proposed. It is shown that the adsorption of mercury(II) is adequately described by the Langmuir isotherm equation for monolayer adsorption on localized sites of energetically homogeneous surfaces. It is established that the considerably increased sorption of mercury nitrate on silica modified by different β-cyclodextrins is due to the formation of 1: 1 β-cyclodextrin-nitrate ion inclusion complexes on the surface and the participation of side functional groups of the upper edge of immobilized β-cyclodextrin molecules in the formation of mixed-ligand mercury(II) complexes.

The isotherms of excess adsorption of argon, nitrogen, and carbon dioxide on adsorbents with various porous structures (active carbon AU-71, polymeric sorbent MN-200, and synthetic zeolite NaA) were measured on the precision volumetric-gravimetric device in the pressure range of 0.1—150 MPa and at temperatures 300—400 K. The results of determination of the adsorption volumes of the studied adsorbents were compared using two methods. The first method is based on the Dubinin-Radushkevich equation, whereas the second one involves a conditional division of the weight of the substance in an ampule into the adsorbed portion and the part existing in the gas phase. The behavior of the adsorbed substance is described by the equation of adsorption of complete content corresponding to the physics of the adsorption process. The relation of the parameters of the empirical Dubinin—Radushkevich equation to the energy characteristics of the system was established.

The interaction of β-cyclodextrin with mercury(II) nitrate has been studied using UV, IR, and 1H NMR spectroscopy, elemental analysis, and quantitative chemical analysis. The optimum conditions for complex formation were established. The stability constant of the 1:1 inclusion complex of β-cyclodextrin and nitrate was calculated. The formation of supermolecules of composition C42H70O35·3Hg(NO3)2 in solution and on a silica surface chemically modified with β-cyclodextrin was shown.

Complex formation between benzene carboxylic acids and β-cyclodextrin in aqueous solutions at 290–300 K was studied using UV spectroscopy. The formation of 1:1 supramolecular inclusion compounds β-cyclodextrin-benzene and β-cyclodextrin-salicylic acid was found. Stability constants (Ks) of the complexes and thermodynamic parameters for formation of the inclusion compounds (ΔG, ΔH, and ΔS) were calculated.

Stable nano-sized nickel particles are prepared using the radiation-chemical synthesis in reverse micelles. Adsorption properties of raw silica (silochrome, S-120), the silochrome modified by a micelle-forming compound (AOT), and the silochrome modified by the nano-sized nickel particles are studied using gas chromatography method. The retention times for different test-compounds at different temperatures are determined for these adsorbents. Specific retention volumes of the test-compounds, as well as the thermodynamic adsorption characteristics, are determined. After the modification, the initial adsorption heat for n-hydrocarbons increases, which points out to the higher surface roughness of the modified samples. For the nickel-nanoparticle-modified silica, the contribution of specific interactions of polar compounds is less than that for the unmodified silica; this can be explained by screening the active centers (OH-groups) of the silica gel by the metal nanoparticles. The silica polarity decreases after the modification. The gas chromatography method allows detecting the difference in the properties of nanocomposites containing Ni- and NiO-nanoparticles.

Two samples of detonation nanodiamond (ND) were studied using gas chromatography. Sample ND-Cr was treated by boiling sulfochromic acid with liquid-phase acid purification. Sample ND-Oz was treated with gaseous ozone. The retention times determined for nine substances of different nature at various temperatures were used to calculate the specific retention volumes and the thermodynamic parameters of adsorption of test compounds on ND-Oz and ND-Cr. The adsorption heats of tested n-hydrocarbons on nanodiamond powders, especially on ND-Oz, are close to those on graphitized carbon black (GTB). For benzene and polar compounds, the specific interaction terms in the total energy of adsorption were determined. These terms are higher for ND-Oz than for ND-Cr; i.e., sample ND-Oz contains more reactive functional groups.

The interaction of β-cyclodextrin with benzoic acid was studied by UV and IR spectroscopy, X-ray diffraction, and thermogravimetry. The introduction of the benzoic acid molecule into the internal hydrophobic β-cyclodextrin cavity and additional stabilization by weak H-bonds caused the formation of 1: 1 axial inclusion complexes of the host—guest type. The degree of crystallinity of the inclusion complex decreased compared with the initial compounds, whereas its thermal stability increased.

Inclusion host-guest complexes are synthesized from β-cyclodextrin and salicylic acid, which is a nonsteroid anti-inflammatory drug with a wide range of action. By IR and UV spectroscopy, and X-ray diffraction, and thermogravimetry, it is established that axial 1:1 complexes of the “tail forward” type are formed due to the dispersion interactions between internal hydrophobic cavities of β-cyclodextrin molecules and salicylic acid aromatic rings. Salicylic acid is stabilized due to the fact that its carboxyl group is located in the plane of the upper edge of β-cyclodextrin molecule and weak hydrogen bond is formed between phenyl hydroxyl and glycoside oxygen. The encapsulation of salicylic acid changes its crystal structure and thermal stability.

The chemical interaction between the surface of hydroxylated or aminated silicas and β-cyclodextrin, mono-tosyl-β-cyclodextrin and the bromine derivative of heptakis-[6- O-( p-tosyl-β-cyclodextrin)] has been investigated using IR spectroscopy, thermogravimetric analysis with programmed heating, pH titration, weight adsorption method, elemental analysis and quantitative chemical analysis of the surface compounds. The optimum conditions for chemical grafting of β-cyclodextrins onto the silica surface were established. The formation of supramolecular structures, viz. inclusion complexes between immobilized β-cyclodextrin and the hormone of pineal gland (melatonin), on the surface of highly dispersed silicas of 1:1 composition was demonstrated.

The chemical interaction between dimethylchlorosilane and silica of varied degree of hydroxylation was subjected to a systematic study. The optimal conditions for complete substitution of isolated silanol groups with dimethyl hydride silyl groups were found. It is suggested that the reaction of dimethylchlorosilane with the surface of silicon dioxide can be used to determine the concentration of free silanol groups in the surface layer of silica.

The solid-phase thermal and catalytic hydrosilylation of N -vinyl-2-pyrrolidone on the surface of hydride silicas has been studied. It was found that thermal polymerization of N -vinyl-2-pyrrolidone is a side reaction of the thermal hydrosilylation of N -vinyl-2-pyrrolidone. During the catalytic hydrosilylation of N -vinyl-2-pyrrolidone, two side reactions took place. These were the interaction of the silicon-hydride groups with water and with propanol-2 and the formation of metallic platinum. The thermal hydrosilylation of N -vinyl-2-pyrrolidone, without the use of catalyst and solvent, is the preferred method for the chemical bonding of N -vinyl-2-pyrrolidone in the surface layer of hydride silicas.

The thermal stability of metal complexes immobilized on the surface of silica and its connection with the catalytic activity in the oxidation of hydrogen were investigated. High catalytic activity was exhibited by heterogenized platinum and palladium acetylacetonate near room temperatures in the initial state and by γ-aminopropylsilicas treated with platinum and palladium complexes. The catalytic activity of the metal complexes correlates with their thermal stability and with the ability to undergo oxidation to a metal state with high valence.

The effect of the conditioning temperature of the hypercross-linked polystyrene sorbents Styrosorb on the retention ofn-hexane, benzene. and acetone was studied by gas chromatography. The rigid but mobile structure of 100% cross-linked polymers with a specific surface area of 300–500 m2 g−1 prepared in cyclohexane slightly shrinks by conditioning above 200 °C. This results in a significant increase in the specific retention volumes of the adsorbates. The commercial hypercross-linked sorbents MN-100 and MN-200 with specific surface areas of −1000 m2 g−1 retain their structure up to 250 °C.

Silica gels with trimethylsilyl and long-chain alkyl (C 6 –C 18 ) groups have been synthesized. It has been established that adsorption of water on silica gels modified with trimethylsilyl groups decreases substantially and varies as a function of the modifier and the synthesis method chosen. The most hydrophobic surface (contact angle Θ =136°) is characteristic of silica modified with trimethyliodosilane vapor at 25°C. It has been shown that the lowest affinity for water ( Θ =110–130°) is characteristic of silica gels modified with hydrocarbon radicals, i.e. of silica gels whose residual silanol groups were end-capped using vapor-phase modification with hexamethyldisilazane or trimethyliodosilane. The results presented account for the differences in hydrophobic properties of surfaces of silica gels modified with trimethylsilyl and long-chain alkyl groups.

The solid phase hydrosilation of N-vinyl-2-pyrrolidone by≡Si−H bonds immobilized on a silica gel surface has been investigated.