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Copolymers of N-vinylpyrrolidone and 2-methyl-5-vinyltetrazole with various ratios of monomer units were synthesized by radical polymerization using the injection method. The copolymerization parameters for these monomers were calculated by the Kelen―Tudos method (r1 = 14.34; r2 = 0.06) for high degrees of conversion. Copolymers with monomer-unit concentrations up to 70 ± 5 mol% were soluble in water, non-toxic, and effective as radioprotectors.

N-Vinylpyrrolidone and 2-methyl-5-vinylpyridine copolymers with various ratios of monomer units and molecular weights were synthesized by radical copolymerization using an injection method. The ratio of monomer units was determined by non-aqueous potentiometric titration and 13C NMR methods. The viscosity-average molecular weights of copolymers containing 35 – 39 mol% of 2-methyl-5-vinylpyridine were in the range 15.2 – 27.6 kDa. Copolymers with 2-methyl-5-vinylpyridine content up to 75 ± 5 mol% exhibited good solubility in water.

Techniques for quantitative determination of N-vinylpyrrolidone and 2-methyl-5-vinylpyridine copolymers in aqueous solutions were developed. The spectrophotometric technique allowed the copolymer concentration in dilute solutions (0.8 – 1.2 mg/mL) to be determined even in the presence of the interfering additive merthiolate. The refractometric technique was simpler and allowed the copolymer concentration in concentrated solutions (> 1 mass%) to be determined.

Aqueous dextran solutions, polyhexamethyleneguanidine hydrochloride and Sovidone and their mixtures with taurine were used to form stable ultrathin protective films for ophthalmological use. Addition of taurine to dextran and polyhexamethyleneguanidine solutions induced an association between polymer macromolecules in the two-dimensional film and a decrease in the surface activity of the solution. Addition of taurine to Sovidone solutions altered the conformation of macromolecular globules and increased the surface activity of the solution. Use of these solutions as the bases for eye drops did not harm the lipid layer of the tear film, and that rapidly formed polymer films could successfully be replaced by natural lipids via natural processes during recovery of the functions of the tear glands.

A new approach to the formulation of eye drops containing the active substance taurine and adjuvant polymers such as dextran, poly(hexamethyleneguanidine) hydrochloride, and Sovidon is proposed. According to this, the eye drop formulation must begin with a study of the physicochemical properties of the polymer and taurine solutions, in particular an evaluation of their surface tension and wettability of a substrate similar to the mucous layer of lacrimal film. The optimal values of the solution concentrations providing effective drug delivery into the intracellular space of epithelial cells were determined.

A copolymer of N-vinylpyrrolidone and 2-methyl-5-vinylpyridine was shown to increase the phagocytic activity of macrophages. A tendency of the fraction of phagocytic cells, the phagocytic index, and the index of phagocytosis completeness to increase was observed after its administration.