Self-assembled magnetic arrays

Patent metadata

Field	Value
Publication number	US-9869619-B2
Application number	US-201615393402-A
Country	US
Kind code	B2
Filing date	Dec 29, 2016
Priority date	Sep 27, 2010
Publication date	Jan 16, 2018
Grant date	Jan 16, 2018

Abstract

A magnetic device includes a substrate and an array including a plurality of magnetic particles, in which a magnetic dipole moment direction of each magnetic particle in a majority of the magnetic particles in the array alternates with respect to a magnetic dipole direction of a directly adjacent magnetic particle or directly adjacent magnetic particles in the array.

First claim

What is claimed is:

1. A magnetic device comprising:
a substrate;
an array including a plurality of magnetic particles arranged in a single layer on the substrate, wherein a magnetic dipole moment direction of each magnetic particle in a majority of the magnetic particles alternates with respect to a magnetic dipole direction of a directly adjacent magnetic particle in the array, wherein an average maximum dimension of each particle of the plurality of magnetic particles is between about 50 nm to about 125 microns, and wherein directly adjacent particles within the array are separated by a spacing of 5 nm or less;
a fluid flow channel having a bottom surface arranged adjacent to the array, wherein the magnetic dipole moment direction of each magnetic particle in the majority of the magnetic particles is oriented substantially orthogonal to the bottom surface of the fluid flow channel.

2. The magnetic device according to claim 1 , wherein the magnetic particles in the array comprise permanent magnets.

3. The magnetic device according to claim 1 , wherein the magnetic particles in the array comprise a superparamagnetic material.

4. The magnetic device according to claim 1 , wherein the magnetic particles in the array comprise one or more of NdFeB, SmCo, FePt, and iron oxide.

5. The magnetic device according to claim 1 , further comprising a suspension layer, wherein the array of magnetic particles is located in the suspension layer.

6. The magnetic device according to claim 5 , wherein the suspension layer comprises a curable polymer.

7. The magnetic device according to claim 6 , wherein the polymer comprises polyurethane, epoxy, poly(methyl methacrylate) (PMMA), or polydimethylsiloxane (PDMS).

8. The magnetic device according to claim 1 , further comprising:
a sheet coated with an adhesive that adheres to the array of magnetic particles.

9. The magnetic device according to claim 1 , wherein the plurality of magnetic particles in the array is close-packed.

10. The magnetic device according to claim 1 , further comprising a plurality of fluid flow channels arranged adjacent to the array.

Assignees

• Massachusetts Gen Hospital

Inventors

• Weissleder Ralph
• Lee Hakho
• Issadore David

Classifications

• G01N2001/4088

  filtration · CPC title

• A61B5/055

  involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging · CPC title

• B03C2201/18

  Magnetic separation whereby the particles are suspended in a liquid · CPC title

• G01N2610/00

  Assays involving self-assembled monolayers [SAMs] · CPC title

• H01F10/007

  ultrathin or granular films (H01F10/005 and H01F10/3227 take precedence; applying ultrathin or granular layers to substrates H01F41/301) · CPC title