Příprava a vlastnosti superparamagnetických anorganicko/polymerních částic pro biolékařské aplikace

Superparamagnetické -Fe2O3 nanočástice byly syntetizovány srážením železitých a železnatých solí alkalickými činidly. Výsledné nanočástice byly povlečeny slupkami, jako je poly(N,N-dimethylakrylamid) (PDMAAm), výchozí i funkcionalizovaná silika (SiO2 a SiO2-NH2) a polyanilin (PANI). PDMAAm slupka byla zavedena modifikací povrchu nanočástic oxidů železa iniciátorem a N,N-dimethylakrylamid byl polymerizován za vzniku -Fe2O3&PDMAAm částic. V případě SiO2-NH2 slupky byl použit tetramethyl-orthosilikát a vznikly -Fe2O3&SiO2 nanočástice, které byly následně modifikovány (3-aminopropyl)triethoxysilanem (γ-Fe2O3&SiO2- NH2 částice). Oxidací anilin hydrochloridu persulfátem amonným ve vodném roztoku poly(N- vinylpyrolidonu) v přítomnosti oxidů železa vznikly -Fe2O3&PANI nanočástice. Poslední typ částic byl pak na bázi thioninem modifikovaného poly(karboxymethyl-methakrylátu) (PCMMA&Th). Částice byly charakterizovány technikami, jako je rastrovací a transmisní elektronová mikroskopie (SEM a TEM) a dynamický rozptyl světla (DLS), které stanovily morfologii a hydrodynamický průměr částic. Přítomnost funkčních skupin, chemické složení a obsah železa byly prokázány infračervenou spektroskopií s Fourierovou transformací (FTIR), dále atomovou absorpční spektroskopií (AAS), prvkovou a mikroprvkovou analýzou...Superparamagnetic -Fe2O3 nanoparticles were synthesized by coprecipitation of ferric and ferrous salts with a base. Resulting nanoparticles were coated with shells, such as poly(N,N- dimethylacrylamide) (PDMAAm), neat and functionalized silica (SiO2 and SiO2-NH2), and polyaniline (PANI). PDMAAm shell was introduced by modification of iron oxide nanoparticle surface with an initiator and N,N-dimethylacrylamide was polymerized producing -Fe2O3&PDMAAm core-shell particles. In case of SiO2-NH2 shell, tetramethyl orthosilicate was used to yield -Fe2O3&SiO2 nanoparticles, which were subsequently modified by (3-aminopropyl)triethoxysilane to prepare γ-Fe2O3&SiO2-NH2 particles. Oxidation of aniline hydrochloride with ammonium persulfate in an aqueous solution of poly(N-vinylpyrrolidone) in the presence of iron oxides produced -Fe2O3&PANI nanoparticles. Finally, the last type of the particles was based on thionin-modified poly(carboxymethyl methacrylate) (PCMMA&Th). The particles were characterized by techniques, such as scanning and transmission electron microscopy (SEM and TEM) and dynamic light scattering (DLS) to determine the particle morphology and hydrodynamic diameter. The presence of the functional groups, chemical composition, and the iron content were investigated by Fourier-transform...Katedra fyzikální a makromol. chemieDepartment of Physical and Macromolecular ChemistryPřírodovědecká fakultaFaculty of Scienc

Preparation and characterization of superparamagnetic inorganic/polymer particles for biomedical application

Superparamagnetic -Fe2O3 nanoparticles were synthesized by coprecipitation of ferric and ferrous salts with a base. Resulting nanoparticles were coated with shells, such as poly(N,N- dimethylacrylamide) (PDMAAm), neat and functionalized silica (SiO2 and SiO2-NH2), and polyaniline (PANI). PDMAAm shell was introduced by modification of iron oxide nanoparticle surface with an initiator and N,N-dimethylacrylamide was polymerized producing -Fe2O3&PDMAAm core-shell particles. In case of SiO2-NH2 shell, tetramethyl orthosilicate was used to yield -Fe2O3&SiO2 nanoparticles, which were subsequently modified by (3-aminopropyl)triethoxysilane to prepare γ-Fe2O3&SiO2-NH2 particles. Oxidation of aniline hydrochloride with ammonium persulfate in an aqueous solution of poly(N-vinylpyrrolidone) in the presence of iron oxides produced -Fe2O3&PANI nanoparticles. Finally, the last type of the particles was based on thionin-modified poly(carboxymethyl methacrylate) (PCMMA&Th). The particles were characterized by techniques, such as scanning and transmission electron microscopy (SEM and TEM) and dynamic light scattering (DLS) to determine the particle morphology and hydrodynamic diameter. The presence of the functional groups, chemical composition, and the iron content were investigated by Fourier-transform..

Highly conducting and biocompatible polypyrrole/poly(vinyl alcohol) cryogels

Conducting macroporous soft cryogels were prepared by the oxidation of pyrrole within the frozen aqueous solutions of 5–8 wt.% poly(vinyl alcohol) at −24 °C. Mechanical properties of cryogels were independent of poly(vinyl alcohol) concentration, Young moduli were ≈20 kPa. The conductivity of compressed freeze-dried composites reached 18 S cm −1 thus exceeding the conductivity of polypyrrole alone. This level of conductivity was also preserved after long-term treatment with water, i.e. close to physiological conditions. In-vitro determined cytotoxicity demonstrated high potential applications due to low cytotoxicity. Moreover, compared to the steel based materials, the cryogels mimic the properties of soft tissues. All these properties are a prerequisite for the utilization in biomedical applications. © 2019 Elsevier B.V.Czech Science Foundation [17-05095S