Luminescent-labeled copolymers of 4-acryloylmorpholine and 2-dialkylaminoethyl methacrylates (2-dimethylaminoethyl methacrylate and 2-diethylaminoethyl methacrylate) of varied compositions and molecular masses were synthesized. Polarized luminescence method was used to study relaxation properties of the polymers in diluted aqueous solutions. The influence of copolymer composition, temperature, pH, ionic strength of solutions on structural and dynamic characteristics of the copolymers in solution was established. The obtained copolymers were used to synthesize silver nanoparticles with an average radius of 7-8 nm. Interaction between the luminescent-labeled copolymers and Ag+ ions was studied. It was demonstrated that reduction of Ag+ by the copolymers and formation of Ag degrees is accompanied by decrease in mobility of polymer chains due to adsorption of macromolecules on the surface of Ag degrees nanoparticles and formation of a stabilizing shell.

The interaction of a molecular brush consisting of a polyimide backbone and luminescence-labeled poly(methacrylic acid) side chains with poly-N-vinylamides (poly-N-vinylpyrrolidone and poly-N-vinylcaprolactam) with different molecular weights is studied via polarized luminescence under stationary excitation in organic solvents with different thermodynamic qualities in relation to the chain blocks of the polymers, namely, selective (methanol) and common (dimethylformamide). The decrease in the mobility of the grafted poly(methacrylic acid) chains with the growth in the molecular weight of poly-N-vinylamide observed in both selective and common solvents gives evidence of the transition from a “loose” structure to a more compact structure of the interpolymer complex. It is shown on the basis of the analysis of the nanosecond relaxation times characterizing the mobility of the sections of the grafted poly(methacrylic acid) chains and reflecting the change in the intra- and intermolecular interactions that the formation of interpolymer complexes in dimethylformamide leads to a looser structure.

Water-soluble polymeric complexones, N -vinylpyrrolidone- N -allyl- p -aminosalicylic acid copolymers with low content of chelating units, were synthesized. The formation of Eu 3+ heteroligand complexes containing these complexones was studied. The complexation of Eu 3+ with the polymeric complexone and low-molecular-mass organic coligand, thenoyltrifluoroacetone (TTA), ensures efficient energy transfer from molecular orbitals of the polymeric ligand to Eu 3+ , allowing the Eu 3+ luminescence intensity in aqueous solutions to be enhanced by more than 1–1.5 orders of magnitude. The maximal intensity of the Eu 3+ luminescence in the heteroligand complex is observed at the [Eu 3+ ]:[COO − ] ratio of ∼1 and [Eu 3+ ]/[TTA] = 1.2−1.5. In the presence of univalent metal salts, the Eu 3+ luminescence intensity does not noticeably change up to their concentration of 0.4 M. Addition of Ca 2+ or Mg 2+ salts leads to a drastic decrease in the Eu 3+ luminescence intensity in the solution.

The formation and structural organization of interpolymer complexes formed by poly(methacrylic acid) chains regularly grafted to polyimide (molecular brushes) and macromolecules of poly(N-vinylamides) with different molecular masses are studied by polarized luminescence. The luminescent label of the anthracene structure is covalently bound to poly(methacrylic acid) chains in a brush. It is shown that in aqueous solutions the complexes under study are stabilized by hydrogen bonds formed between proton donor and proton acceptor groups of interacting chains. The formation of these complexes depends not only on the nature of poly(N-vinylamide) but also especially on its molecular mass. An increase in the molecular mass of polyamide is followed by the formation of a more compact less hydrated structure, as proved by an increase in the time of nanosecond relaxation and enhanced binding of the diphilic organic ion. The hindrance of poly(methacrylic acid) grafted chains complexed with polyvinylamide is lower than that of corresponding linear chains. This can be explained by a higher imperfection of the formed double-stranded structures. The ionization of carboxyl groups leads to the dissociation of complexes. The pH range corresponding to the highest degree of binding of acridine orange by poly(methacrylic acid) grafted chains is broader than that corresponding to the highest degree of dye binding by the linear polyacid.

Theoretical fundamentals of using the polarized luminescence method for studying the nanosecond dynamics of polymers in solution are presented. The efficiency of using the steady-state polarized luminescence method for studying the relaxation characteristics of synthetic linear polymers and conformational transitions in dilute solutions has been demonstrated. The results of investigating relaxation properties of copolymers of complex architecture by an example of polymer brushes, starshape polymers and dendrimers in solution are discussed also.

Quenching of the luminescence of carboxyl-containing polymer molecules containing a luminescent marker by transition metal ions (Cu2+, Ni2+) is observed not only in aqueous and aqueous-salt solutions, but also in polar organic solvents (methanol, ethanol, dimethylformamide). In dilute solutions, quenching refl ects binding of metal ions with the polymer and changes in the degree of filling of the polymer carboxyl groups with transition metal ions quenching the luminescence. The equilibrium stability constant of the formed macromolecular metal complex in organic media can be quantitatively estimated from the quenching effect using the relationships that follow from the law of mass action. The formation and stability of Cu2+ and Ni2+ complexes with polymethacrylic acid in protic (methanol, ethanol) and aprotic (dimethylformamide) solvents at low polymer concentrations (0.4–0.02 mg mL–1) were studied using the quenching effect. In methanol, in contrast to ethanol and dimethylformamide, two mechanisms of binding of transition metal ions with different equilibrium stability constants of the complexes (\({K_{{1^{st}}}}\) > 3 × 109 and \({K_{{2^{st}}}}\) ≈ 106–104) were revealed. The infl uence exerted on the stability of the complexes and on the complexation mechanism by the nature and acidity of the organic solvent, polymer concentration, kind of the transition metal ion quenching the luminescence, and NaOH and HCl additions was studied. The results obtained demonstrate the efficiency of the luminescence method used and prospects for its further use for studying polymer systems containing transition metal ions in organic solvents.

The synthesis of luminescent-labeled copolymers of octa-tert-butylcalix[8] arene with 8 poly-2isopropyl-2-oxazoline arms is carried out. Each macromolecule involves one luminescent label of the anthracene structure located at the end of one of the arms. The luminescent properties of the copolymers in water and methanol are studied. It is shown that, in aqueous solutions, the formation of intermolecular aggregates with a hydrophobic core and a hydrophilic shell results in a new photophysical process of migration of electron excitation energy accompanied by a decrease in the solution luminescence polarization. The interaction of oxazoline arms with poly(methacrylic acid) via the mechanism of interpolymer complex formation implies a weakening of the efficiency of energy migration.

Using luminescent methods, interactions of rare earth metal ions (Tb3+, Eu3+, Sm3+, Gd3+) with side chains of ionized polymethacrylic acid (PMAA) regularly grafted to a polyimide (PI) backbone are studied in aqueous and aqueous-salt solutions. It is shown that the interaction of ions with carboxylate anionic groups leads to a sharp decrease in the intramolecular mobility of grafted PMAA side chains at the ratio [metal]/[СОО−] > 0.12. It is established that the luminescence duration of Tb3+ ions decreases from 790 to 660 μs when the degree of polymerization of side PMAA chains decreases from 200 to 36. By means of the methodology based on the ability of transition metal ions to quench luminescence, equilibrium stability constants of macromolecular complexes of transition metal ions (Ag+, Cu2+, Ni2+) with luminescent-labeled PI-grafted and free PMAA chains in aqueous and aqueous-salt solutions are determined. It is shown that the complex stability is essentially affected by the nature and valence of a metal and the ionic strength of solution. Grafting of PMAA chains to a PI backbone causes no significant effect on their ability to bind Ag+ and Cu2+ ions, but reduces considerably the ability of binding with Ni2+ ions. An explanation of this effect is suggested.

A method based on the ability of transition-metal ions to quench the fluorescence of labeled polymer molecules is developed to determine the equilibrium stability constants of macromolecular complexes of Ag + , Cu 2+ , and Ni 2+ with the copolymers of 2-deoxy-2-methacrylamido- D -glucose and unsaturated carboxylic acids (methacrylic or acrylic) in aqueous and aqueous–saline media. The stability constants of the complexes strongly depend on the type of transition-metal, the copolymer composition, and the ionic strength of solution, but weakly depend on the type of introduced low-molecular-mass electrolyte and the chemical structure of the carboxyl-containing units.

Методом поляризованной люминесценции изучены структурно-динамические характеристики звездообразного полимера с центральным трет-бутилкаликс[8]ареновым звеном и лучами поли(N-изобутироилэтиленимин)- -пиперазина в водных растворах. Для проведения исследований к полимеру была присоединена люминесцирующая метка антраценовой структуры. Показано, что в воде макромолекулы полимера находятся в агрегированном состоянии. Агрегат состоит примерно из 5 макромолекул. При смешении звездообразного полимера с макромолекулами неионизованной полиметакриловой кислоты формируется мицелла со смешанной оболочкой, в которой звенья полиметакриловой кислоты взаимодействуют как со звеньями поли(N-изобутироилэтиленимин)- -пиперазина, так и с изобутильными звеньями, входящими в ядро мицеллы.

Physicochemical and molecular properties of complexes formed by aminoglycoside antibiotics, including neomycin, gentamicin, kanamycin, and amikacin, in the form of bases and carboxyl- or sulfo-comprising copolymers of acrylamide or N-(2-hydroxypropyl)methacrylamide have been studied. The toxicity of complexes in vitro and their antimicrobial activity are matched to their behavior in solutions. Direct dependency of toxic and antibacterial properties of polymer complexes of aminoglycoside antibiotics on their molecular characteristics and stability opens up perspectives of targeting control over their antimicrobial activity by changing the microstructure of their polymer carrier chains.

Structural and dynamic characteristics of a star-shaped polymer with a central tert -butylcalix[8]arene core and poly( N -isobutyryl ethylenimine)-ω-piperazine arms in aqueous solutions were studied via the polarized-luminescence method. To conduct investigations, a luminescent label of the anthracene structure was attached to the polymer. It has been shown that polymer macromolecules are in an aggregate state in water. The aggregate comprises about 5 macromolecules. During mixing of the star-shaped polymer with macromolecules of un-ionized poly(methacrylic acid), a mixed-shell micelle in which poly(methacrylic acid) units interact with both poly( N -isobutyryl ethylenimine)-ω-piperazine moieties and isobutyl fragments incorporated into the core of the micelle is formed.

Polarized luminescence and flow birefringence methods were used in the studies of structural and dynamic characteristics of 2-(diethylamino)ethyl methacrylate and 2-deoxy-2-methacrylamido-d-glucose copolymers with varied content of cationic monomer units while changing temperature, pH and ionic strength of solutions. It was demonstrated that with increasing temperature, nanosecond relaxation times τIMM (which characterize intramolecular mobility of fragments of copolymer chain in solution) increase over a relatively narrow temperature range. Increase in relaxation times indicates strengthening intramolecular interactions and the formation of intramolecular hydrophobic domains. From the obtained flow birefringence data, it follows that in the vicinity of the lower critical solution temperature (LCST) we have molecular dispersed diluted copolymer solutions. The influence of temperature and ionic strength of solutions on the transition temperature were also studied. The observed changes in intramolecular interactions are accompanied by insignificant changes in root-mean-square dimensions of macromolecular coils; however, coils retain their asymmetry.

Методами молекулярной гидродинамики (седиментация, диффузия, вискозиметрия), поляризованной люминесценции и двойного лучепреломления в потоке исследованы конформационные и релаксационные свойства образцов сополимеров N,N-диметиламиноэтилметакрилата и 2-деокси-2-метакриламидо-D-глюкозы в растворах. Получены уравнения Марка–Куна–Хаувинка и выполнена оценка длины статистического сегмента Куна при различных степенях протонирования аминогрупп. Установлена корреляция между длиной статистического сегмента Куна и внутримолекулярной подвижностью сополимеров.