Keywords: magnetite, superparamagnetic nanoparticles, synthesis, functionalisation, iron oxide nanoparticles, nanotechnology, monodisperse functionalised nanoparticles, colloidal stability, phosphate buffered saline, high salt concentration
Preparation of monodisperse functionalised superparamagnetic nanoparticles
Monocrystalline iron oxide nanoparticles were synthesised by a one-pot procedure using iron salts in benzyl alcohol and functionalised with dopamine and carboxylmethylated dextran. Dextran macromolecules with low and high carboxyl contents were synthesised and grafted onto the dopamine-functionalised nanoparticles. The particles were characterised using X-ray photoelectron spectroscopy (XPS), infrared spectroscopy (IR), transmission electron microscopy (TEM) and dynamic light scattering (DLS). Monodisperse functionalised nanoparticles were obtained with a hydrodynamic diameter of 20?50 nm. The functionalisation also provided excellent colloidal stability in phosphate buffered saline, even at high salt concentration.