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Nanoparticles (NPs), due to their size, have a key position in nanotechnology as a spectrum of solutions in medicine. NPs improve the ability of active substances to penetrate various routes: transdermal, but also digestive (active endocytosis), respiratory and injection. Chitosan, an N-deacetylated derivative of chitin, is a natural biodegradable cationic polymer with antioxidant, anti-inflammatory and antimicrobial properties. Cross-linked chitosan is an excellent matrix for the production of nanoparticles containing active substances, e.g., the Ginkgo biloba extract (GBE). Chitosan nanoparticles with the Ginkgo biloba extract (GBE) were obtained by ion gelation using TPP as a cross-linking agent. The obtained product was characterized in terms of morphology and size based on SEM and Zeta Sizer analyses as well as an effective encapsulation of GBE in nanoparticles—FTIR-ATR and UV-Vis analyses. The kinetics of release of the active substance in water and physiological saline were checked. Biological studies were carried out on normal and cancer cell lines to check the cytotoxic effect of GBE, chitosan nanoparticles and a combination of the chitosan nanoparticles with GBE. The obtained nanoparticles contained and released GBE encapsulated in research media. Pure NPs, GBE and a combination of NPs and the extract showed cytotoxicity against tumor cells, with no cytotoxicity against the physiological cell line. [ABSTRACT FROM AUTHOR]

By interfacial esterification of sucrose with methacryloyl chloride, an ester derivative of sucrose-methacryloyloxysucrose was prepared, which contains vinyl side groups. The structure of methacrylated sucrose (MS) was determined by means of FTIR, H NMR, and C NMR spectra. The MS was used as new cross-linker to cross-link poly(2-hydroxyethyl methacrylate). The influence of the amounts of cross-linking agent on the swelling behavior of these hydrogels was studied. Differential scanning calorimetry (DSC) was used for measuring the different states of water in hydrogel materials. DSC date showed that the content of freezing water in hydrogel decreased with growth of MS percentage. [ABSTRACT FROM AUTHOR]

Abstract  A new polymeric system containing hydrolysable ester bond linked to salicylic acid to be used for controlled drug release was synthesized. Poly(2-hydroxyethyl methacrylate) (PHEMA) functionalized with chloroacetate groups was obtained by the reaction between PHEMA and chloroacetyl chloride using the N,N-dimethylacetamide/5% lithium chloride system as a solvent and pyridine as a catalyst. The degree of substitution was calculated from the chlorine content and ranged from 32.2 to 98.1 mol.% depending on the ratio of chloroacetyl chloride to PHEMA. The coupling of salicylic acid to PHEMA functionalized with chloroacetate groups was carried out by the reaction between PHEMA and the sodium salt of salicylic acid. The structures of chloroacetylated PHEMA and PHEMA–salicylic acid conjugates were determined by means of FTIR, 1H-NMR and 13C-NMR spectra. The hydrolysis in the heterogeneous system of PHEMA–salicylic acid conjugates were performed in buffer solutions (pH 7.6 and 8.5) at 37 °C and showed that the release of the drug (sodium salicylate) from tablets was dependent on the hydrophilic character of conjugate as well as on the pH value of the medium. [ABSTRACT FROM AUTHOR]