Dynamic Magnetic Cell Sorting

Patent metadata

Field	Value
Publication number	US-2016370279-A1
Application number	US-201615179484-A
Country	US
Kind code	A1
Filing date	Jun 10, 2016
Priority date	Jun 17, 2015
Publication date	Dec 22, 2016
Grant date	—

Abstract

A microfluidic magnetic selector comprises a microfluidic channel comprising at least one bifurcation, forming a selection portion of the selector and splitting the microfluidic channel into a main channel and at least one selection channel; at least one magnetic flux concentrator for concentrating a magnetic flux at the level of the bifurcation, and means for generating a magnetic field within the magnetic flux concentrator, and a controller for controlling magnetic pulses through the magnetic flux concentrator.

First claim

1 . A microfluidic magnetic selector comprising
a microfluidic channel comprising at least one bifurcation, forming a selection portion of the microfluidic magnetic selector and splitting the microfluidic channel into a main channel and at least one selection channel, at least one magnetic flux concentrator for concentrating a magnetic flux at the level of the bifurcation, and a means for generating a magnetic field within the magnetic flux concentrator, and a controller for controlling magnetic pulses through the magnetic flux concentrator.

2 . The microfluidic magnetic selector of claim 1 , wherein the at least one magnetic flux concentrator comprises a ferromagnetic material with a saturation magnetization of at least 0.5 Tesla.

3 . The microfluidic magnetic selector of claim 1 , wherein the at least one magnetic flux concentrator comprises a tip with a dimension between 10 nm and 0.1 mm.

4 . The microfluidic magnetic selector of claim 1 , wherein the at least one selection channel is connected to the microfluidic channel, the connection between the microfluidic channel and the at least one selection channel comprising the at least one magnetic flux concentrator.

5 . The microfluidic magnetic selector of claim 1 , further comprising conducting coils surrounding the magnetic flux concentrator as a means for generating a magnetic field.

6 . The microfluidic magnetic selector of claim 1 , wherein the microfluidic channel is configured to convey a fluid comprising at least one target particle exhibiting superparamagnetic, ferromagnetic or paramagnetic behavior in presence of a magnetic field.

7 . The microfluidic magnetic selector of claim 6 , wherein the at least one target particle is linked to at least one ferromagnetic, superparamagnetic or paramagnetic bead

8 . The microfluidic magnetic selector of claim 1 , wherein the magnetic pulses comprise the magnetic field varying between at least two pre-determined values of amplitude, frequency, or pulse width.

9 . The microfluidic magnetic selector of claim 1 , wherein the means for generating a magnetic field comprises an anisotropic magneto-resistive head or a giant magneto-resistive head.

10 . An integrated circuit comprising the microfluidic magnetic selector according to claim 1 .

11 . A method for magnetic selection of target particles, the method comprising
providing a fluid comprising at least one target particle exhibiting superparamagnetic or paramagnetic behavior in presence of a magnetic field, flowing of the fluid through a microfluidic magnetic selector, the magnetic selector comprising a microfluidic channel comprising at least one bifurcation forming a selection portion of the selector and splitting the microfluidic channel into a main channel and at least one selection channel, and at least one magnetic flux concentrator, pulsing magnetic flux through the at least one magnetic flux concentrator and into the flowing fluid, by means of the magnetic flux, deflecting the at least one target particle through the at least one bifurcation into the at least one selection channel.

12 . The method according to claim 11 , wherein providing a fluid comprising at least one target particle exhibiting superparamagnetic, ferromagnetic or paramagnetic behavior in presence of a magnetic field comprises providing a fluid wherein the at least one target particle is linked to at least one ferromagnetic, superparamagnetic or paramagnetic bead.

13 . The method according to claim 11 , further comprising estimating the average momentum of the at least one target particle, and wherein pulsing magnetic flux through the magnetic flux concentrator comprises pulsing magnetic flux at a frequency such that the at least one target particle can be deflected through the at least one bifurcation into the selection channel, and any other particle in the fluid may not be deflected through the at least one bifurcation.

14 . The method according to claim 11 , further comprising estimating the average momentum of the at least one target particle, and wherein pulsing magnetic flux through the magnetic flux concentrator comprises pulsing magnetic flux with a magnetization field strength such that at least one target particle can be deflected through the at least one bifurcation into the selection channel, and any other particle in the fluid may not be deflected through the at least one bifurcation.

15 . The method according to claim 11 , wherein pulsing magnetic flux comprises alternating the magnetic flux concentrator with a magnetic field amplitude stronger than a coercivity field of the magnetic flux concentrator.

16 . The method according to claim 11 , wherein pulsing magnetic flux further comprises pulsing magnetic flux at frequencies between 0.1 MHz and 1 GHz.

17 . The method according to claim 11 , wherein the magnetic flux is pulsed via conducting coils surrounding the magnetic flux concentrator.

18 . The method according to claim 11 , wherein the pulsed magnetic flux comprises the magnetic field varying between at least two pre-determined values of amplitude, frequency, or pulse width.

19 . The method according to claim 11 , wherein pulsing the magnetic flux comprises adjusting an anisotropic magneto-resistive head or a giant magneto-resistive head.

20 . An integrated circuit configured to carry out the method of claim 11 .

Assignees

• Imec Vzw

Inventors

• Min Richard
• Lagae Liesbet
• Liu Chengxun
• Huang Chengjun

Classifications

• B01L3/502761 Primary

  specially adapted for handling suspended solids or molecules independently from the bulk fluid flow, e.g. for trapping or sorting beads or physically stretching molecules · CPC title

• B01L2400/043

  magnetic forces · CPC title

• B01L2300/12

  Specific details about materials · CPC title

• G01N15/1056

  Physics · mapped topic

• B01L2200/0652

  Sorting or classification of particles or molecules · CPC title