RESUMEN
Magnetic nanoparticles are the next tool in medical diagnoses and treatment in many different biomedical applications, including magnetic hyperthermia as alternative treatment for cancer and bacterial infections, as well as the disruption of biofilms. The colloidal stability of the magnetic nanoparticles in a biological environment is crucial for efficient delivery. A surface that can be easily modifiable can also improve the delivery and imaging properties of the magnetic nanoparticle by adding targeting and imaging moieties, providing a platform for additional modification. The strategy presented in this work includes multiple nitroDOPA anchors for robust binding to the surface tied to the same polymer backbone as multiple poly(ethylene oxide) chains for steric stability. This approach provides biocompatibility and enhanced stability in fetal bovine serum (FBS) and phosphate buffer saline (PBS). As a proof of concept, these polymer-particles complexes were then modified with a near infrared dye and utilized in characterizing the integration of magnetic nanoparticles in biofilms. The work presented in this manuscript describes the synthesis and characterization of a nontoxic platform for the labeling of near IR-dyes for bioimaging.
Asunto(s)
Biopelículas , Dihidroxifenilalanina/química , Colorantes Fluorescentes/química , Legionella pneumophila , Nanopartículas/química , Polietilenglicoles/química , Animales , Bovinos , Legionella pneumophila/citología , Legionella pneumophila/fisiología , Ratones , Microscopía FluorescenteRESUMEN
PURPOSE: Gene therapy strategies are a promising new alternative option in the treatment of cancer diseases and great effort is dedicated to the development of new gene transfer methods. At present, in vitro cell culture experiments or in vivo animal trials are the only available alternatives in the search for new gene transfer methods. We attempted to develop and evaluate a new 3D matrix model as a step between in vitro experiments and animal trials. MATERIALS AND METHODS: We generated a convenient model with an agarose gel as a basis for small intestinal submucosa or a polyethylene membrane. The produced model consisting of human smooth muscle cells and human bladder carcinoma cells was transfected with a modified standard Lipofectamine trade mark 2000 transfection procedure and visualised by fluorescence microscopy after cryo-sectioning. RESULTS: With the help of this new technique it is possible to generate three dimensional tissues consisting of different types of cells in which the cells are adherent on the polyethylene and the SIS-membrane during the entire treatment. The resulting model was successfully transfected with the pEGFP-N1 plasmid. CONCLUSIONS: This new three dimensional model allows the standardised evaluation of new transfection methods on multilayered ex-vivo generated tissues consisting of different cells.