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In water–DMF at DMF content less than 2.6 mol dm−3, deuteroporphyrin IX dimethyl ester forms both H- and J-aggregates. The J-aggregates are detected as a single type of associated species after binding of the porphyrin with BSA on the surface of the protein IB subdomain.

Glycosized porphyrins are promising compounds for using in PDT, since they combine the ability to act as a photosensitizer, and their saccharide residues provide an increased tumorotropicity of this compound in the affected cells. In this work, the modified 5,10,15,20-tetrakis [4-(2,3,4,6-tetra-O-acetyl-β-D-galactopyranosyl) phenyl] porphine (HOGalPor) synthesis procedure providing an increased yield of the desired product is described. The affinity of natural biopolymers with reference to synthesized porphyrin has been studied. It was found that synthesized porphyrin is associated in aqueous media. There were proposed some mixed solvents and water-solvent concentration ratios were established to ensure the monomerization of porphyrin and the preservation of the native conformation of biopolymers (BSA and DNA). The affinity constants of BSA and DNA were determined with reference to the synthesized porphyrin, as well as localization of porphyrin in biopolymers was established. As part of the protein complex, porphyrin fluoresces very intensively, and this feature makes it possible to use BSA as a transport system for HOGalPor, and HOGalPor itself can act as a fluorescent marker. The interaction of HOGalPor with the intercalation complex of DNA-EtBr leads to the destruction of the latter, while porphyrin does not intercalate in DNA, but forms external complexes with a change in the zeta potential of the surface.

Thermal stability of polyvinyl alcohol/cellulose nanocrystals composites has been studied. It has been shown that nanocrystalline cellulose in its acid form considerably enhances the thermal stability of the composites, while the neutral form of the nanocrystalline cellulose has little effect on the thermal stability of the composites.

The surface of silica particles was modified with polyvinyl pyrrolidone (PVP) through solegel process. The different experimental techniques, i.e., thermogravimetric analysis (TGA and DTG), nitrogen adsorption, scanning electron microscopy (SEM), laser diffraction analysis (LDA), fourier transform spectroscopy (FTIR) are used to characterize the pure non-functionalized and functionalized silicas containing different amount of PVP. It was shown that PVP-modified silica samples have well developed porous structure; the values of specific surface area for PVP-modified silicas are in the range of 140 e264 m 2 g � 1 . While the non-functionalized silica shows the low surface area (S BET ¼ 40 m 2 g � 1 ). The BJH analysis showed that PVP can be used as an effective agent to increase an average pore size and total pore volume. The results indicate that PVP functionalized silicas show a potential as effective adsorbents for bilirubin removal compared to other available adsorbents.

The enthalpies of solution and solvation of ethylene oxide oligomers CH3O(CH2CH2O)nCH3 (n = 1 to 4) in methanol and chloroform have been determined from calorimetric measurements at T = 298.15 K. The enthalpic coefficients of pairwise solute–solute interaction for methanol solutions have been calculated. The enthalpic characteristics of the oligomers in methanol, chloroform, water and tetrachloromethane have been compared. The hydrogen bonding of the oligomers with chloroform and water molecules is exhibited in the values of solvation enthalpy and coefficient of solute–solute interaction. This effect is not observed for methanol solvent. The thermochemical data evidence an existence of multi-centred hydrogen bonds in associates of polyethers with the solvent molecules. Enthalpies of hydrogen bonding of the oligomers with chloroform and water have been estimated. The additivity scheme has been developed to describe the enthalpies of solvation of ethylene oxide oligomers, unbranched monoethers and n-alkanes in chloroform, methanol, water, and tetrachloromethane. The correction parameters for contribution of repeated polar groups and correction term for methoxy-compounds have been introduced. The obtained group contributions permit to describe the enthalpies of solvation of unbranched monoethers and ethylene oxide oligomers in the solvents with standard deviation up to 0.6 kJ · mol−1. The values of group contributions and corrections are strongly influenced by solvent properties.

Silica materials with different surface functionalities were synthesized by sol–gel method. The isothermal enthalpies of adsorption of human serum albumin ( Δ a d s H H S A ) onto the silica surfaces from buffer solution (pH = 7.4) were measured at 298.15 K. The values of Δ a d s H H S A were found to be endothermic. Possible contributions to Δ a d s H H S A are discussed.

The enthalpies of solution of 12-crown-4 ether have been measured in chloroform, ethyl acetate, acetone, pyridine, acetonitrile and methanol at 298.15 K. The values of enthalpy of solvation and solute–solvent interaction were determined from the obtained results and similar literature data for 12-crown-4 in solvents of various polarities. It was shown that the certain correlation is observed between the enthalpy of solute–solvent interaction and the squared dipole moment of the solvent molecules for solutions in tetrachlormethane, ethyl acetate, pyridine, acetonitrile, DMF, DMSO and propylene carbonate. This means that the electrostatic interaction of 12-crown-4 with polar solvent molecules contributes significantly to the exothermic effect of solvation. The understated negative value was found for the enthalpy of interaction of 12-crown-4 with acetone that can be connected with domination of low polar conformer of the crown ether in acetone medium. The most negative values of enthalpy of solvation are observed for solutions in chloroform and water because of hydrogen bonding between O-atoms of crown ether and molecules of the indicated solvents. This effect is not observed for methanol. The negative coefficient of pairwise solute–solute interaction in methanol indicates that the effects of solvophobic solute–solute interaction and H-bonding of the ether molecule with chain associates of methanol are not evinced in the thermochemical behavior of 12-crown-4.

The enthalpies of solution Δ sol H m of straight-chain polyethers CH 3 O(CH 2 CH 2 O) n CH 3 ( n = 1–4) have been measured in water and tetrachlormethane as inert reference solvent at temperature of 298.15 K. The enthalpic coefficients of pairwise interaction and enthalpies of solvation were determined. The interaction between ether molecules in inert solvent are dominated by electrostatic forces resulting in the negative coefficients of interaction. In water the coefficients of interaction are positive. This is because the partial destruction of hydrophobic and hydrophilic shells becomes the predominant contribution to the coefficient. The enthalpy of solvation of one ethane oxide group in water is more negative than in tetrachlormethane by −7.4 kJ mol −1 that was related to the prevailing contribution of hydrogen bonding between ether and water molecules. The comparison of enthalpic characteristics was performed for the open-chain and cyclic ethers. The more exothermic effect of hydration of CH 2 CH 2 O group is observed for cyclic ethers. The distinction is connected with strengthening of hydrogen-bond bridges between adjacent ether oxygen atoms in cyclic molecule.

The enthalpies of solution of 1,4,7,10,13,16-hexaoxacyclooctadecane at infinite dilution have been determined in tetrachloremetane, benzene, chloroform, toluene, ethyl acetate, pyridine, acetone, dimethylformamide, dimethylsulfoxide, methanol, acetonitrile, benzyl alcohol, and water at temperature of 298.15 K. The comparison of the results obtained for the enthalpy of solution indicates the presence of specific interactions of 1,4,7,10,13,16-hexaoxacyclooctadecane with water and acetonitrile. From the data on the enthalpies of solution, values of the enthalpy of solvation in the solvents were determined. This property was in turn decomposed into enthalpy of cavity formation and solute–solvent interaction, calculated with scaled particle theory. Correlation of enthalpies of solvation with the enthalpy of cavity formation and molecular parameters of the solvents were obtained.