Magnetic nanoparticle formulations, methods for making such formulations, and methods for their use

1. A magnetic nanoparticle (MNP) comprising

(a) a core iron oxide nanoparticle;

(b) first layer of cyclodextrin bound directly to the iron oxide of the core nanoparticle; and

(c) a second layer of a poly(ethylene-co-propylene glycol) polymer bound directly to the cyclodextrin layer, wherein the second layer is the outer layer of the MNP.

2. The MNP of claim 1 , wherein the core nanoparticle is between about 5 nm and about 30 nm in diameter.

3. The MNP of claim 1 , wherein the cyclodextrin is selected from the group consisting of α-cyclodextrin, β-cyclodextrin, and γ-cyclodextrin, and derivatives thereof.

4. The MNP of claim 1 , wherein the cyclodextrin comprises β-cyclodextrin, or derivatives thereof.

5. The MNP of claim 1 , wherein the MNP comprises a molar ratio of between about 1:40 to 1:300 cyclodextrin:iron ion in the core nanoparticle.

6. The MNP of claim 1 , wherein the MNP comprises a molar ratio of between about 1:1 and 1:10 cyclodextrin:poly(ethylene-co-propylene glycol).

7. The MNP of claim 1 , wherein the MNP further comprises a therapeutic loaded into the MNP and/or a photosensitizer loaded into the MNP.

8. An MNP cluster, comprising a plurality of MNPs according to claim 1 , wherein the MNP cluster is between about 50 nm and about 200 nm in diameter.

9. The MNP cluster of claim 8 , wherein the MNP cluster is between about 75 nm and about 150 nm in diameter.

10. A method for making the magnetic nanoparticle (MNP) of claim 1 , comprising

(a) precipitating iron salts in the presence of ammonia to obtain an iron oxide core nanoparticle; and

(b) coating the iron oxide core nanoparticle with:

(i) cyclodextrin; and

(ii) an outer layer of poly(ethylene-co-propylene glycol).

11. The method of claim 10 , wherein the cyclodextrin is selected from the group consisting of α-cyclodextrin, β-cyclodextrin, and γ-cyclodextrin, and derivatives thereof.

12. The method of claim 10 , wherein the cyclodextrin comprises β-cyclodextrin, or derivatives thereof.

13. The method of claim 10 , wherein the MNP comprises a molar ratio of between about 1:40 to 1:300 cyclodextrin:iron ion in the core nanoparticle.

14. The method of claim 10 , wherein the MNP comprises a molar ratio of between about 1:1 and 1:10 cyclodextrin: poly(ethylene-co-propylene glycol).

15. The method of claim 10 , wherein the method further comprises loading a therapeutic into the MNP and/or loading a photosensitizer into the MNP.

16. A method for drug delivery, comprising administering the MNP of claim 1 , wherein a drug is loaded into the MNP, to a subject in need thereof.

17. A method for hyperthermic treatment, comprising

(a) administering the MNP of claim 1 to a subject in need thereof so as to localize the MNP to the vicinity of a tissue of interest, and

(b) applying an alternating magnetic field to produce heat from the MNP;

wherein the heat produced from the MNP damages cells in the tissue and/or sensitizes cells in the tissue to other therapy.

18. A method for photodynamic treatment (PDT), comprising

(a) administering the MNP of claim 1 , wherein the MNP further comprises a photosensitizer, to a subject in need of PDT; and

(b) applying a light source to excite the photosensitizer;

wherein the excitation of the photosensitizer produces reactive oxygen species that damage cells in the relevant tissue.

19. A method for in vivo imaging comprising

(a) administering the MNP of claim 1 to a subject in need of magnetic resonance imaging; and

(b) conducting magnetic resonance imaging (MRI) on the subject;

wherein the MRI permits in vivo imaging of the relevant tissue.