# US 9,873,126 B2 · Devices and methods for separating particles

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 9,873,126 B2
- Document ID: US9873126B2
- Status: Granted
- Kind: B2
- Application number: 15/290,700
- Filed: 2016-10-11
- Published: 2017-03-16
- Granted: 2018-01-23
- Earliest claimed: 2012-05-18
- Assignees: University of Georgia Research Foundation, Inc.
- Applicants: University of Georgia Research Foundation, Inc.
- Inventors: Leidong Mao; Taotao Zhu; Mark A. Eiteman
- Web page: https://patentgrep.com/patent/US9873126B2

## CPC

- B03C 1/288: {disposed at the outer circumference of a recipient}
- B03C 1/32: acting on the medium containing the substance being separated, e.g. magneto-gravimetric-, magnetohydrostatic-, or magnetohydrodynamic separation
- C12N 13/00: Treatment of microorganisms or enzymes with electrical or wave energy, e.g. magnetism, sonic waves
- G01N 27/74: of fluids (G01N24/00 takes precedence)
- B03C 2201/18: Magnetic separation whereby the particles are suspended in a liquid
- B03C 2201/26: for use in medical or biological applications
- B03C: MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS (separating isotopes B01D59/00; combinations of magnetic or electrostatic separation with separation of solids by other means B03B, B07B)
- C12N: MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA (microbiological testing media C12Q1/00)
- G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q)

## Abstract

Embodiments of the present disclosure provide for devices, methods for separating particles, and the like.

## Claims

### Claim 1

A method for separating particles from a liquid comprising a magnetic fluid and at least two types of particles having different volumes, the method comprising:
flowing the liquid down a channel having two or more outlets in fluidic communication with the channel;
exposing the magnetic fluid to a non-uniform magnetic force to control the non-uniform magnetic force exerted on the particles and magnetic buoyancy force experienced by the particles; and
separating the at least two types of particles into different outlets of the two or more outlets based on the magnetic buoyancy force and the volume of the particles;
wherein the particles are cells.

### Claim 2 (depends on 1)

The method of claim 1, wherein the at least two types of particles are separated at a rate of about 106 particles per hour to about 109 particles per hour.

### Claim 3 (depends on 1)

The method of claim 1, wherein the cells are selected from the group consisting of bacterial cells, yeast cells, blood cells, cancer cells, neural cells, and sperm cells.

### Claim 4 (depends on 1)

The method of claim 1, wherein each of the cells has a volume of 5 μm3 to 3000 μm3.

### Claim 5 (depends on 1)

The method of claim 1, wherein the particles are separated based upon a difference in the magnetic buoyancy force experienced due to the different volumes of the particles.

### Claim 6 (depends on 1)

The method of claim 1, wherein the channel has two or more fluid inlets in fluidic communication with the channel,
wherein the method further comprises flowing the at least two types of particles through a first fluid inlet and flowing the magnetic fluid through a second fluid inlet to form the liquid.

### Claim 7 (depends on 6)

The method of claim 6, wherein the first fluid inlet includes at least two turns prior to the channel.

### Claim 8 (depends on 1)

The method of claim 1, wherein the channel includes three or more outlets for separating particles based upon the different volumes.

### Claim 9 (depends on 1)

The method of claim 1, wherein the channel has a tapered diameter along a portion of the length of the channel.

### Claim 10 (depends on 1)

The method of claim 1, wherein a magnet disposed on one side of the channel generates the non-uniform magnetic force.

### Claim 11 (depends on 10)

The method of claim 10, wherein the magnet is a permanent magnet.

### Claim 12 (depends on 1)

The method of claim 1, wherein the magnetic fluid is a colloidal mixture of nano-size magnetic particles covered by a surfactant.

### Claim 13 (depends on 12)

The method of claim 12, wherein the nano-size magnetic particles have a diameter of 5 nm to 10 nm.

### Claim 14 (depends on 1)

The method of claim 1, wherein the magnetic fluid is a ferrofluid, a paramagnetic solution, or a combination thereof.