RESUMO
Magnetic nanoparticles have been used for biomedical purposes for several years. In recent years, nanotechnology has developed to a stage that makes it possible to engineer particles to provide opportunities for the site-specific delivery of drugs. To this end, a variety of iron oxide particles have been synthesized. The size and surface of the particles are crucial factors in the application of the particles. Therefore, this study involves the use of two types of magnetic nanoparticles derivatized with elastin and synthesized with differing diameters, compared with identical underivatized plain particles. This influence in vitro was assessed using human dermal fibroblasts and various techniques to observe cell-particle interaction, including light and fluorescence microscopy and scanning electron microscopy. The results indicate that derivatized particles induce alterations in cell behavior and morphology distinct from the plain particles, suggesting that cell response can be directed via specifically engineered particle surfaces. However, little difference was observed between the different diameters.
Assuntos
Materiais Revestidos Biocompatíveis/farmacologia , Elastina/química , Elastina/farmacologia , Fibroblastos/citologia , Fibroblastos/fisiologia , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Proliferação de Células/efeitos dos fármacos , Tamanho Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Materiais Revestidos Biocompatíveis/química , Fibroblastos/efeitos dos fármacos , Humanos , Teste de Materiais , Tamanho da PartículaRESUMO
Calix[4]arene tetraethers in the cone conformation bearing four -NH-CO-CH2-P(O)Ph2 (= CMPO) residues on their wide rim and one, two or four omega-amino alkyl residues of various lengths at the narrow rim were synthesized. Reaction with dichlorotriazinyl (DCT) functionalized magnetic particles led to complete coverage of the available surface by covalently linked CMPO-calix[4]arenes in all cases. Magnetically assisted removal of Eu(iii) and Am(iii) from acidic solutions was distinctly more efficient with these particles in comparison to analogous particles bearing the same amount of analogous single-chain CMPO-functions. The best result, an increase of the extraction efficiency by a factor of 140-160, was obtained for attachment via two propyl spacers. The selectivity Am/Eu was in the range of 1.9-2.8. No decrease of the extraction ability was observed, when the particles were repeatedly used, after simple back extraction with water.