Abstract: The present invention relates to a method of forming iron oxide nanoparticles comprising the steps of (a) suspending iron oxide/hydroxide and oleic acid or a derivative thereof in a primary organic solvent; (b) increasing the temperature of the suspension by a defined rate up to a maximum of 340° C. to 500° C.; (c) aging the suspension at the maximum temperature of step (b) for about 0.5 to 6 h; (d) cooling the suspension; (e) adding a secondary organic solvent; (f) precipitating nanoparticles by adding a non-solvent and removing excess solvent; (g) dispersing said nanoparticles in said secondary organic solvent; (h) mixing the dispersion of step (g) with a solution of a polymer; and (i) optionally removing said secondary organic solvent.

Abstract: The present invention relates to a method of forming an iron oleate complex comprising the steps of: (a) dissolving an oleate in a low-order alcohol solvent at a temperature of about 35° C. to 65° C.; (b) adding a non-polar solvent to the solution of step (a); (c) adding an iron salt dissolved in a low-order alcohol to the solution of step (b); (d) agitating the solution of step (c) at a temperature of about 50° C. for at least 5 min; (e) cooling the reaction mixture of step (d) to a temperature of about 15° C. to 30° C.; (f) optionally filtering the reaction mixture of step (e); (g) separating the non-polar solvent phase from the low-order alcohol phase; (h) washing and drying the non-polar solvent phase; (i) removing volatiles from the non-polar solvent phase of step (h) by evaporation; and (j) mixing the product of step (i) with a polar solvent to yield a solid iron oleate complex.