Iron Oxide Nanoparticles
Iron oxide (IO) nanoparticles consist of maghemite (γ-Fe2O3) and/or magnetite (Fe3O4) particles with diameters ranging from 1 and 100 nanometer and find applications in magnetic data storage, biosensing, drug-delivery etc. In nanoparticles (NPs), the surface area to volume ratio increases significantly. This allows a considerably higher binding capacity and excellent dispersibility of NPs in solutions. Magnetic NPs, with sizes between 2 and 20 nm display superparamagnetism, i.e their magnetization is zero, in the absence of an external magnetic field and they can be magnetized by an external magnetic source. This property provides additional stability for magnetic nanoparticles in solutions.