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Porous microparticles of chitosan- g -poly(glycidyl methacrylate) were obtained by grafting chitosan onto crosslinked networks based on glycidyl methacrylate and ethylene glycol dimethacrylate using suspension polymerization technique. A new cephalosporin from the indazole class prepared by acylation of 7-Aminodesacetoxycephalosporanic acid with mixed anhydride of 5-nitroindazole-1-yl-acetic acid was used as active principle. The cephalosporin-microparticle systems were characterized by FT-IR spectroscopy, SEM and AFM analysis. Batch experiments were carried out to study the influence of initial drug concentration, temperature, contact time, drug:microparticles ratio and pH on the adsorption process of cephalosporin onto porous crosslinked microparticles. Two-parameter and three-parameter isotherm models were used to evaluate the adsorption equilibrium. The values of diffusion coefficients indicate that the cephalosporin adsorption onto microparticles was controlled by both film diffusion and pore diffusion mechanisms. The analysis of the kinetic data of the release process indicate that the release mechanism of cephalosporin from microparticles corresponds to the anomalous transport mechanism.

The synthesis of some new derivatives of p-aminobenzoic acid and the temperature dependence of the electrical conductivity and Seebeck coefficient for these compounds are studied. The measurements have been performed using thin films deposited from solutions. Investigated compounds show semiconducting properties. Some correlations between these properties and the chemical structure are established. The values of some characteristic parameters (activation energy, ratio of carrier mobilities, etc.) of the studied compounds have been determined.

The synthesis of some new derivatives of the asparagic acid is described and the temperature dependence of the electrical conductivity and Seebeck coefficient for respective compounds are studied. The measurements have been performed using the thin films deposited from the solution. Investigated compounds have semiconducting properties. Some correlations between these properties and chemical structure of the compounds are established. The values of some characteristic parameters (activation energy, ratio of carrier mobilities etc.) of the studied compound have been determined.