High performance hybrid magnetic structure for biotechnology applications

• US 20070182517A1
• Filed: 11/09/2006
• Published: 08/09/2007
• Est. Priority Date: 11/30/2001
• Status: Active Grant

• Current Assignee: Regents of the University of California (University of California)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: Elkin, Christopher, Humphries, David, Pollard, Martin
• Granted Patent: US 7,486,166 B2
• Time in Patent Office: Days
• US Class Current: 335/306
• CPC Class Codes: B01L 2300/0829 Multi-well plates; Microtitration plates
• CPC Class Codes: B01L 3/5085 for multiple samples, e.g. microtitration plates
• CPC Class Codes: B03C 1/0332 using permanent magnets
• CPC Class Codes: B03C 1/288 disposed at the outer circumference of a recipient
• CPC Class Codes: B03C 2201/18 Magnetic separation whereby the particles are suspended in a liquid
• CPC Class Codes: B03C 2201/22 characterised by the magnetic field, e.g. its shape or generation
• CPC Class Codes: B03C 2201/26 for use in medical or biological applications
• CPC Class Codes: H01F 7/0252 PM holding devices H01F7/021, H01F7/0215, H01F7/0226 take precedence

Abstract

The present disclosure provides a high performance hybrid magnetic structure made from a combination of permanent magnets and ferromagnetic pole materials which are assembled in a predetermined array. The hybrid magnetic structure provides means for separation and other biotechnology applications involving holding, manipulation, or separation of magnetic or magnetizable molecular structures and targets. Also disclosed are further improvements to aspects of the hybrid magnetic structure, including additional elements and for adapting the use of the hybrid magnetic structure for use in biotechnology and high throughput processes.

Claims

1. A hybrid magnetic structure comprising:

a. a non-magnetic base;

b. a ferromagnetic pole;

c. at least two blocks of permanent magnet material;

wherein the at least two blocks of permanent magnet material are assembled onto said base on opposite sides of and adjacent to said ferromagnetic pole, in a periodic array, and have the magnetization orientations oriented in opposing directions and orthogonal to the height of said ferromagnetic pole, and wherein said blocks of permanent magnet material extend below the bottom edge of said ferromagnetic pole when assembled onto said base; and

,

wherein the ferromagnetic pole has a shaped tip which extends in a longitudinal direction from a bottom edge to a shaped tip which extends beyond each block of permanent magnet material and wherein said shaped tip is shaped to allow close proximity with a containment vessel.

2. The hybrid magnetic structure of claim 1, further comprising two ferromagnetic poles, one on each end of said periodic array.

3. The hybrid magnetic structure of claim 1, further comprising at least one retainer adjacent the outermost block of magnetic material.

4. The hybrid magnetic structure of claim 1, further comprising a pair of opposing retainers extending orthogonally to the magnetization orientation.

5. The hybrid magnetic structure of claim 1, having a magnetic field strength of at least 6000 Gauss.

6. The hybrid magnetic structure of claim 1, wherein said shaped tip has notches to adjust the field gradient produced.

7. The hybrid magnetic structure of claim 1, wherein said shaped tip features a chamfer allowing the pole to contour the shape of the containment vessel and maintain close proximity.

8. The hybrid magnetic structure of claim 7, wherein said shaped tip is within 1-2 mm of the containment vessel.

9. The hybrid magnetic structure of claim 1, wherein the non-magnetic base is aluminum.

10. The hybrid magnetic structure of claim 1, wherein the ferromagnetic pole is made of steel or vanadium pemendur.

11. The hybrid magnetic structure of claim 1, wherein the blocks of permanent magnet material comprise a rare earth element.

12. The hybrid magnetic structure of claim 11, wherein the blocks of permanent magnet material comprise neodymium iron boron or samarium cobalt.

13. The hybrid magnetic structure of claim 1, further comprising an upper interface attached on top of the hybrid magnetic structure.

14. The hybrid magnetic structure of claim 1, further comprising a retainer rod running through the structure orthogonal to the height of the ferromagnetic pole.

15. The hybrid magnetic structure of claim 1, further comprising a lower locator plate attached to the bottom of the hybrid magnetic structure.

16. The hybrid magnetic structure of claim 1, further comprising a field adjustment element assembled beneath a selected ferromagnetic pole, wherein said field adjustment element comprises a lower block of permanent magnet material whose magnetization orientation is facing into or out of said pole such that the magnetization orientations of all blocks of permanent magnet material around each pole piece are uniformly facing either out of or into the pole.

17. The hybrid magnetic structure of claim 1, further comprising a protective cover.

18. The hybrid magnetic structure of claim 1, further comprising a return yoke.