The synthesis of polymeric nanocapsules loaded with the antituberculosis drug Capreomycin sulphate is presented in this work. The pHresponsive polymeric nanocapsules were successfully synthesized using the RAFT-based vesicle templating approach in the presence of Capreomycin sulphate. Anionic small polyelectrolytes comprising randomly distributed butyl acrylate and acrylic acid units were adsorbed on cationic vesicles of dimethyldioctadecyl ammonium bromide (DODAB). N,N-(dimethylamino)ethyl methacrylate (DMAEMA) and methyl methacrylate (MMA) or tertiary butyl methacrylate (tBMA) and MMA were used for the formation of the polymeric shells. Subsequently the tBMA was hydrolyzed to obtain negatively charged nanocapsules. The nanocapsule morphology for both approaches was characterized by DLS and TEM. The most stable hollow latex particles were obtained with the monomer composition of DMAEMA:MMA = 1:1. These nanocapsules were found to be colloidally stable and pH-responsive. The entrapment efficiency of drug determined by UV-Vis-spectroscopy was 70 %. The drug release rate from nanocapsules at pH 6.5 was found to be relatively fast (substantial release within one hour already), however we believe slower release can be achieved by using a thicker polymer shell.

This article considers someaspects of synthesis and characterizationof polylactide-co-glycolide nanoparticles immobilized withthe antituberculous drug isoniazid. The influence of some synthesis parameters of nanoparticles (the ratio of drug substance:polymer and surfactant concentration) onproperties of the obtained nanosomal drug form of isoniazid has been studied. Optimal conditions for obtainingthenanoparticles with the best physicochemical parameters such as: particle size, polydispersity, conversion, etc. have been found. These nanoparticlescan be used asdrug carriers.The results revealed thata polymer: drug ratio of 1:1 and the use of 3% Twin 80 are necessaryto obtain stable emulsions of nanoparticles of polylactide-co-glycolide with satisfactory characteristics. Average size of the obtained particles was 196.4 nm,and the polydispersity value was 0.323. The aggregation stability of nanoparticles during 4 hours at temperatures of 4ºC and 20ºC has been evaluated. The morphology of the obtained nanoparticles has been studied.Analysis of nanoparticles was characterized by various instrumental methods includinggas chromatography and thermogravimetrytechniques. The resulting nanoparticles of polylactide-co-glycolide immobilized with isoniazid are stable in time andcanprolong the action of the drug. In vitrorelease of isoniazid from polylactide-co-glycolide nanoparticles hasbeen studied.

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Thermal decomposition of the copolymer of polyethylene glycol fumarate with acrylic acid (p-EGF:AA) of two different compositions synthesized earlier was studied in the present work. TG and DTG curves prove that decomposition takes place in several stages. According to thermogravimetric curves it has been found out that for the copolymer with higher content of acrylic acid the decomposition of the copolymer’s sample is started at higher temperatures. It has been shown the shift of the temperature of decomposition’s start to the higher area with the increase of heating rate which is necessary for the detorsion of macromolecular coil. Experimental data processed using graphical methods of Kissinger–Akahira–Sunose and Friedman allowed us to calculate the activation energy of the thermal decomposition process. It has been established that the copolymer with the composition of 21.03:78.97 mass.% has lower meaning of activation energy than the one with the composition of 68.96:31.04 mass.%. As a result of calculation one can see that the meanings found out using these methods depend slightly on conversion. Using Achar-Brindley-Sharp method and the method of invariant kinetic parameters the kinetic triplet of the decomposition process has been found which was used to build the calculated curve. The dependences of g(α) on α using these parameters showed a satisfactory agreement of calculated curves with the experimental ones. One can conclude that the decomposition process of the copolymer of polyethylene glycol fumarate with acrylic acid is well described with of D3 (three-dimensional diffusion) model.