Device and Method for Separating Magnetic or Magnetizable Particles form a Liquid

• US 20080308500A1
• Filed: 01/28/2006
• Published: 12/18/2008
• Est. Priority Date: 02/02/2005
• Status: Active Grant

• Current Assignee: Revvity Chemagen Technologie GmbH
• Original Assignee: chemagen Biopolymer-Technologie AG (Revvity, Inc.)
• Inventors: Brassard, Lothar A
• Granted Patent: US 9,023,212 B2
• Time in Patent Office: Days
• US Class Current: 210/695
• CPC Class Codes: B03C 1/033 characterised by the magnetic circuit
• CPC Class Codes: B03C 1/06 with magnets moving during operation
• CPC Class Codes: B03C 1/286 disposed at the inner circumference of a recipient, e.g. magnetic drain bolt
• CPC Class Codes: B03C 1/30 Combinations with other devices, not otherwise provided for
• 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 magnetical field, special shape or generation
• CPC Class Codes: B03C 2201/26 for use in medical applications

Abstract

A device (10) is provided for separating magnetic or magnetizable particles from a liquid by using a magnetic field. The device includes a head piece (3) with one or more magnetizable bars (4) which is/are permanently or detachably connected with the head piece (3), as well as one or more permanent magnets (1) whose relative position with respect to the head piece can be changed by a predeterminable movement of the magnet(s) or/and by a predeterminable movement of the head piece.

Claims

1-31. -31. (canceled)

32. A device for separating magnetic or magnetizable particles from a liquid by using a magnetic field, wherein the device (10) comprises

a head piece (3) with at least one magnetizable bar (4) connected in a fixed or detachable manner with the head piece (3);

at least one permanent magnet (1) whose relative position with respect to the head piece can be changed by a predeterminable movement of the magnet or/and by a predeterminable movement of the head piece, such that the permanent magnet assumes a first position above the head piece, or a second position outside the first position.

33. The device according to claim 32, wherein the magnetizable bar (4) is attached to a base plate (9) and forms a unit therewith the base plate to being detachably connected with the head piece (3).

34. The device according to claim 33, wherein the plate (9) is provided with a plurality of magnetizable bars (4) arranged in at least one row, each row containing a plurality of bars (4).

35. The device according to claim 33, wherein the bars (4) or the base plate (9) together with the bars (4) attached thereto are detachably connected with the head piece and/or removable therefrom by at least one actuator selected from the group consisting of electromotive, pneumatic, electromagnetic, and hydraulic drives.

36. The device according to claim 32, wherein the bar (4) is provided with a strippable, replaceable shell (8).

37. The device according to claim 36, comprising a plurality of the shells which form a common unit (8′

).

38. The device according to claim 36, wherein the replaceable shell (8) is retainable at the bar (4) or at the head piece (3), or removable from the bar (4) or the head piece (3) by at least one actuator selected from the group consisting of electromotive, pneumatic, electromagnetic, and hydraulic drives.

39. The device according to claim 32, wherein the head piece is arranged so as to be moveable and can be set into motion by a drive device, the drive device comprising at least on of electromotive, pneumatic, electromagnetic or hydraulic drives.

40. The device according to claim 39, wherein the head piece (3) is moveably arranged such that it is able to perform at least one type of motion indicated below:

translatory movements in a horizontal plane;

movements along a circular path, an elliptic path or an irregular path, in each case within a horizontal plane; and

movements in a vertical direction, the vertical direction corresponding substantially to the longitudinal direction of the magnetizable bars (4′

).

41. The device according to claim 32, further comprising a holder (6) for at least one sample vessel (7).

42. The device according to claim 41, wherein the holder (6) is arranged so as to be moveable and the holder (6) can be set in motion by a drive, such that the sample vessel (7) can be positioned within a region lying below the bar (4) or outside the region, the drive of the holder (6) comprising at least one of electromotive, pneumatic, electromagnetic, and hydraulic drives.

43. The device according to claim 41, wherein the holder (6) is moveably arranged in such a manner that it is able to perform at least one type of motion set out below:

translatory movements in a horizontal plane;

movements along a circular path, an elliptic path or an irregular closed path, in each case within a horizontal plane; and

movements in a vertical direction, the vertical direction corresponding substantially to the longitudinal direction of the magnetizable bars (4).

44. The device according to claim 41, wherein the holder (6) is a component of a program-controlled laboratory robot system and is adapted such that a plurality of individual ones or groups of the sample vessel (7) is alternately moved into a position below the bar (4) and subsequently, after a predeterminable time interval, again into a position which is outside the region below the bar.

45. The device according to claim 41, wherein vertical movement of the holder (6) can be adjusted or controlled by an open-loop control unit or a closed-loop control unit, such that an upward movement of the holder (6) causes the bar (4) to be immersed in the sample vessel (7), which is filled with liquid.

46. The device according to claim 32, wherein at least one of the head piece and the holder is capable of performing shaking or vibrating movements.

47. The device according to claim 32, wherein the head piece is permanently attached to the magnetizable bar.

48. The device according to claim 32, wherein the permanent magnet (1) is displaceably arranged, such that the magnet can be moved from outside into the region located above the head piece (3), and then again out of the region.

49. The device according to claim 32, wherein the permanent magnet (1) is arranged so as to be rotatable or tiltable.

50. The device according to claim 32, wherein the movement of the permanent magnet is accomplished by a drive device comprising at least one electromotive, pneumatic, electromagnetic, and hydraulic drives.

51. The device according to claim 32, further comprising a program-controlled processor connected thereto, such that at least one of the following functions of the device can be open-loop controlled or closed-loop controlled, or such that at least two of the functions mentioned below can be coordinated with one another:

movement of the permanent magnet (1), particularly the time intervals within which the magnet is positioned above the magnetizable bar (4);

movement of the head piece (3) in at least one of horizontal and vertical directions, particularly duration, frequency and amplitude of a shaking or vibrating motion;

actuating detachable attachment of a base plate (9) to the head piece (3) and removal of the base plate from the head piece;

actuating retaining of a shell (8) at the bar (4) and removing the shell (8) from the bar (4);

movement of a holder (6) to position at least one sample vessel (7) alternately below the bar (4) and subsequently to remove the vessel from that position, particularly velocity and frequency of the movements, as well as the dwell time of the holder below the bar;

vertical movement of the holder (6) to immerse the bar (4) into a liquid of the vessel (7) and remove the bar therefrom;

particularly immersion depth, duration and frequency; and

if provided, rotation, shaking or vibrating motion of the holder (6), particularly rotation speed, rotation amplitude and intervals between individual operation phases.

52. The device according to claim 32, further comprising at least one of the below-mentioned means, whose functions are coordinated with functions of the device by a common control:

thermostatable heating or cooling means;

pipetting stations for metered addition of liquids, especially reagents;

suction means for exhausting liquid from a sample vessel by suction;

means for shaking or intermixing a liquid contained in the sample vessel/ and;

analytic apparatuses, particularly for photometric measuring or luminescence detection.

53. An arrangement of magnetizable bars for use in a device for separating magnetic or magnetizable particles according to claim 32, wherein a plurality of magnetizable bars (4) is arranged on a base plate (9), the bars (4) being oriented substantially parallel to one another and arranged in at least one row comprising at least two bars.

54. The arrangement according to claim 53, wherein the magnetizable bars (4) form a unit with the base plate (9) made in one piece by deep drawing.

55. An arrangement of shells for use in a device for separating magnetic or magnetizable particles from a liquid according to claim 32, wherein a plurality of shells (8), which can be slipped onto the magnetizable bars, is arranged substantially parallel to one another, in at least one row comprising at least two bars.

56. The arrangement according to claim 55, wherein the shells (8) are connected so as to form a common unit (8′

) made in one piece by deep drawing.

57. A method for separating magnetic or magnetizable particles from a liquid by using a magnetic field, performed by a device according claim 32, the method comprising the following steps:

a) immersing at least one magnetizable bar of the device into the liquid containing the particles;

b) activating a magnetic field by changing a position of the permanent magnet relative to the magnetizable bar, such that the permanent magnet assumes a position above the head piece, and such that the bar is magnetized and the particles accumulate substantially at a lower end of the bar; and

c) removing the bar, along with the adhering particles, from the liquid.

58. The method according to claim 57, wherein the liquid used in step (a) contains a target substance which is bound specifically, but reversibly, to the particles.

59. The method according to claim 58, further comprising the following additional steps:

d) immersing the bar, along with the particles adhering thereto, in a predetermined volume of a wash liquid;

e) deactivating the magnetic field by an opposite change of the position of the permanent magnet such that the permanent magnet assumes a position which is not above the head piece, whereby the particles are released into the liquid;

f) mixing;

g) magnetizing the bar by changing the position of the permanent magnet, such that the permanent magnet assumes a position above the head piece, and such that the particles accumulate substantially at the lower end of the bar; and

h) lifting the bar out of the wash liquid.

60. The method according to claim 58, further comprising the following additional steps:

i) immersing the bar, along with the particles adhering thereto, into a predetermined volume of an elution liquid that causes the elution of a target substance from the particles; and

k) lifting the bar out of the elution liquid, during which step the particles remain adhering to the bar and are thereby separated from the liquid.

61. The method according to claim 57, further comprising at least one of the below-mentioned steps:

l) detachably attaching a first group of magnetizable bars or a plurality of bars connected to form a common unit a device comprising at least one arranged permanent magnet (1) whose relative position with respect to the magnetizable bars can be changed;

m) separating or discarding the first group of magnetizable bars from the device, and replacing by a second group of magnetizable bars which is detachably attached to the device.

62. The method according to claim 57, further comprising at least one of the below-mentioned steps:

n) slipping a first group of shells or shells connected to form a common unit on the magnetizable bar of a device comprising a head piece (3) with at least one magnetizable bar (4) connected in a fixed or detachable manner with the head piece (3); and

at least one permanent magnet (1) whose relative position with respect to the head piece can be changed by a predeterminable movement of the magnet or/and by a predeterminable movement of the head piece, such that the permanent magnet assumes a first position above the head piece, or a second position outside the first position; and

o) stripping off or discarding the first group of shells from the magnetizable bar of the device and replacing by a second group of shells which is slipped onto the bar.