Patent ID: 8507283

Claim:
A stimuli-responsive magnetic nanoparticle responsive to a magnetic field, comprising: (a) a solid metal oxide core responsive to a magnetic field; and (b) a plurality of stimuli-responsive polymer molecules each having a proximal end comprising a micelle-forming moiety and a distal end comprising a stimuli-responsive moiety, wherein the micelle-forming moiety of each of the plurality of stimuli-responsive polymer molecules becomes incorporated within the solid metal oxide core by: (i) providing a first solution of the plurality of stimuli-responsive polymer molecules in a solvent that is a poor solvent for the micelle-forming moiety; (ii) forming a micelle in the first solution, wherein the micelle dimensions are spatially defined by the micelle-forming moieties; (iii) providing a second solution of a metal compound that is a precursor to the metal oxide core; (iv) introducing the second solution into the micelle, wherein the second solution is more soluble in the micelle than in the first solution, causing the second solution to preferentially concentrate in the micelle; and (v) solidifying the precursor within the micelle in order to incorporate the micelle-forming moiety of each of the plurality of stimuli-responsive polymer molecules within a solid metal oxide core; wherein the stimuli-responsive moiety is self-associative in response to a stimulus.