В обзоре представлены современные достижения в области синтеза биоразлагаемых полимеров на основе лактида различной топологии, а также проведен анализ основных методов получения наночастиц, перспективных для создания систем адресной доставки лекарственных препаратов.

A new hydrophobizator - tetra(ethoxy)di(octyl)disiloxane (TEDODS) - was synthesized in an ethanol solution at boiling point for 6 hours and characterized by NMR and IR spectroscopy. New hydrophobic coatings based on this compound were obtained under mild conditions by direct chemical modification of the surfaces of the cellulose materials (textile of different composition). The formation of a modified layer on the materials surface occurs due to the interaction of the ethoxy groups of the modifier and the hydroxyl groups of cellulose followed by heat treatment to fix it on the materials surface. The optimal conditions for obtaining the coatings were determined: 8% TEDODS weight gain with maximum hydrophobicity, with a wetting angle of 135°. The properties of the modified cellulose materials were studied (hydrophobicity, moisture absorption, etc.). The efficiency of using tetraethoxydioctyldisiloxane as a hydrophobizator when the content from 1% and a relatively small thickness of the coating of 2 microns was shown. It was found that hydrophobic coatings on the surface of cellulosic materials have little effect on moisture absorption and breathability of the original tissue.

It is known that some synthetic polymers can enhance the stability of some proteins including enzymes against thermal denaturation. An important example of such behaviour is poly-N-vinylcaprolactam (PVC), although the mechanism of this phenomenon is not fully understood. This paper deals with this problem with the system PVC-trypsin as an example. PVC is a polymer, which has lower critical solution temperature (LCST) in aqueous solution. It is shown that the rate of enzymatic hydrolysis of a substrate – benzoyl arginine – n-nitroanilide (BAPNA) – with trypsin in aqueous solutions of PVC at 25oC is higher than that in the buffer solution. It is supposed that this effect is a consequence of the complex formation of trypsin with PVC affecting the conformation of the protein and binding of the substrate. The complexation brings about a decrease of the Michaelis constant and an increase of the rate of the biocatalyst interaction with the substrate. It is found that the activity of trypsin depends on the ratio of the enzyme to the substrate. The complexation of trypsin to poly-N-vinylcaprolactam can have influence on the enzymatic activity of the protein at temperatures above LCST, as well as on trypsin trapping in the precipitating polymer. It is noted that, when one determines the enzyme activity by spectral methods, it is necessary to take into account the possibility of complex formation of the polymer with another substance in the reaction system, which can cause errors.