New carboxysilane-coated iron oxide nanoparticles for nonspecific cell labelling.
Magnetic resonance imaging (MRI) offers the possibility of tracking cells labelled with a contrast agent and evaluating the progress of cell therapies. This requires efficient cell labelling with contrast agents. A basic incubation of cells with iron oxide nanoparticles (NPs) is a common method. This study reports the synthesis at the gram scale of iron oxide nanoparticles as MRI T₂ contrast agents for cell labelling. These NPs are based on small iron oxide cores coated with a thin polysiloxane shell presenting carboxylic acid functions. The iron oxide cores produced have been characterized by transmission electron microscopy, X-ray diffraction, ζ-potential, infrared, photon correlation spectroscopy, atomic force microscopy, magnetometry and relaxometric measurements. These measurements confirmed the expected surface modification by carboxysilane. Carboxylic groups created electrostatic repulsion between NPs when they are deprotonated. Therefore, highly concentrated aqueous solutions of carboxysilane coated iron oxide NPs can be obtained, up to 70% (w/w). These NPs could be used for cell labelling owing to their aggregation and re-dispersion properties. NPs precipitated in Dulbecco's modified Eagle medium induced a rapid association with 3 T6 fibroblast cells and could easily be re-dispersed in phosphate buffer saline solution to obtain properly labelled cells.
['Bridot|Jean-Luc|JL|', 'Stanicki|Dimitri|D|', 'Laurent|Sophie|S|', 'Boutry|Sébastien|S|', 'Gossuin|Yves|Y|', 'Leclère|Philippe|P|', 'Lazzaroni|Roberto|R|', 'Vander Elst|Luce|L|', 'Muller|Robert N|RN|']
D000818:Animals D002460:Cell Line D020099:Coated Materials, Biocompatible D003287:Contrast Media D005290:Ferric Compounds D005347:Fibroblasts D058185:Magnetite Nanoparticles D051379:Mice D012833:Siloxanes D013194:Staining and Labeling
iron oxide nanoparticles cell labelling contrast agent colloidal stability ferrofluids silane