Stable selenium nanoparticles were synthesized in a sodium carboxymethylcellulose (Na-CMC) solution with a degree of substitution of 0.85 and an average molar weight of 250 000. The shape and size of selenium nanoparticles were determined by dynamic light scattering and UV spectroscopy. It was found that the nanoparticles coated with Na-CMC are stable upon storage for 28 days. A significant prolongation of the release of the prospidine antitumor agent from stabilized nanoparticles has been shown. Broad spectrum drugs, in particular, anticancer drugs and drugs that compensate for selenium deficiency in the body can be produced based on the selenium nanoparticles coated with Na-CMC.

The physicochemical and biological properties of hydrogels based on starch, dextran, and cellulose phosphates synthesized in orthophosphoric acid–tributyl phosphate–phosphorus(V) oxide and orthophosphoric acid–urea systems are studied. It is found the apparent first step ionization constants of phosphate groups lie in the range of 2.5–2.9 and are virtually independent of the nature of the initial polysaccharide, the means of esterification, and the concentration of functional groups. It is concluded that the differences between the potentiometric curves of the titration of weakly acidic groups are due to the presence of polysaccharide phosphates. Carbamate groups contribute to the formation of a more cross-linked structure of hydrogels, making it difficult to ionize phosphate groups in the second stage. It is established that gel-forming phosphorylated polysaccharides exhibit antitumor activity.

Gel-forming starch phosphates with a content of acidic phosphate groups ranging from 2.1 to 3.8 mmol/g were obtained in a phosphoric acid-urea system. The rates of starch phosphate degradation in buffer solution in the absence of amylase and in the presence of this enzyme were investigated in vitro. Starch phosphate gels were shown to be prone to enzymatic degradation. However, the rate of biodegradation decreased gradually as the content of phosphate groups increased. The use of microgels with average particle sizes in the range of 7.8–60.1 μm for the production of controlled-release preparations of interferon-alpha 2b has been demonstrated to be possible in principle.

The influence exerted by the conditions of the synthesis of dextran phosphate hydrogels in the orthophosphoric acid–urea system on their functional composition and swellability in water was studied. The main parameters of the polymer network, namely, the mean molecular mass of segments between cross-linking points, the pore size, and the cross-linking density, were determined. Samples of prospidin immobilized on dextran phosphate hydrogels were prepared, and the kinetics of the cytostatic release into phosphate buffer solution (pH 7.4) was studied in relation to the functional composition and parameters of the polymer network of the support. The prospidin release from dextran phosphate hydrogels is due both to diffusion processes and to breakdown of the polymer network of the hydrogel.

Исследовано межмолекулярное взаимодействие проспидина с гелеобразующими фосфатами декстрана и крахмала. Изучены сорбционные равновесия этого цитостатика и биодеградируемых гидрогелей фосфатов полисахаридов. Рассчитаны концентрационные коэффициенты равновесия ионного обмена и коэффициенты распределения проспидина при разной степени заполнения фазы микрогелей цитостатиком, показана их связь со степенью набухания гидрогелей. Определены величины ионнообменной и необменной составляющих сорбции. Анализ коэффициентов распределения свидетельствует о том, что концентрация необменно сорбированного проспидина превышает его концентрацию во внешнем растворе, что объясняется наличием ван-дер-ваальсовых взаимодействий между катионами проспидина и макромолекулами фосфатов полисахаридов. Оптимальным носителем проспидина является Na-форма фосфатов полисахаридов, которая характеризуется более высокой плотностью отрицательного суммарного заряда по сравнению с их Н-формой.