Magnetic nanoparticles

Patent metadata

Field	Value
Publication number	US-9623126-B2
Application number	US-201514593293-A
Country	US
Kind code	B2
Filing date	Jan 9, 2015
Priority date	May 26, 2010
Publication date	Apr 18, 2017
Grant date	Apr 18, 2017

Abstract

A magnetic nanoparticle includes a magnetic core and a superparamagnetic outer shell, in which the outer shell enhances magnetic properties of the nanoparticle. The enhanced magnetic properties of the magnetic nanoparticle allow for highly sensitive detection as well as diminished non-specific aggregation of nanoparticles.

First claim

What is claimed is:

1. A nanoparticle comprising:
a solid ferromagnetic core;
a super-paramagnetic shell on a surface of and surrounding the magnetic core, wherein the super-paramagnetic shell has a thickness between about 0.5 nm and about 3 nm.

2. The nanoparticle of claim 1 , wherein the nanoparticle has a diameter greater than or equal to about 2 nm.

3. The nanoparticle of claim 1 , wherein the ferromagnetic core has a core diameter in a range of about 1 nm to about 15 nm.

4. The nanoparticle of claim 1 , wherein the ferromagnetic core comprises Fe, Co, Ni, FePt or SmCo.

5. The nanoparticle of claim 1 , wherein the super-paramagnetic shell comprises an oxide of a magnetic material.

6. The nanoparticle of claim 1 , wherein the super-paramagnetic shell comprises a dopant material.

7. The nanoparticle of claim 6 , wherein the dopant material comprises a metal selected from the group consisting of Mn, Co, Ni, Zn, and ZnMn.

8. The nanoparticle of claim 1 , further comprising a coating on the super-paramagnetic shell, wherein the coating is configured to increase the aqueous solubility of the nanoparticle.

9. The nanoparticle of claim 8 , wherein the coating comprises 2,3-dimercaptosuccinic acid (DMSA).

10. The nanoparticle of claim 1 , further comprising a coating on the super-paramagnetic shell, wherein the coating is configured to bind the nanoparticle to a target molecule.

11. The nanoparticle of claim 1 , further comprising a dextran polymer coating on the super-paramagnetic shell.

Assignees

• Massachusetts Gen Hospital

Inventors

• Weissleder Ralph
• Lee Hakho
• Yoon Tae-Jong

Classifications

• B22F1/08

  Metallic powder characterised by particles having an amorphous microstructure · CPC title

• B22F1/17

  Metallic particles coated with metal · CPC title

• A61K9/5094 Primary

  Microcapsules containing magnetic carrier material, e.g. ferrite for drug targeting · CPC title

• A61K33/30

  Zinc; Compounds thereof · CPC title

• A61K2300/00

  Mixtures or combinations of active ingredients, wherein at least one active ingredient is fully defined in groups A61K31/00 - A61K41/00 · CPC title