Method for performing immunoassays under weightlessness

Abstract

A method for controlled movement of magnetic carriers in a sample volume for performing immunoassays under weightless or reduced-weight conditions, wherein the magnetic carriers are moved inside the sample volume by means of permanent magnets movably arranged relative to at least one spatial axis of the sample volume.

Claims

1. A method for moving magnetic carriers in a controlled manner in a sample volume for performing immunoassays under weightlessness, comprising: providing the sample volume in a vessel for performing immunoassays under weightlessness in which no sedimentation and no convective heat transfer occurs in the sample volume due to the weightlessness; the magnetic carriers are moved within the sample volume by permanent magnets slidably arranged relative to at least one spatial axis of the sample volume; the permanent magnets arranged on one spatial axis are moved synchronized in phase to mix the magnetic carriers; and the permanent magnets are shifted into a parking position and protected by a screening device when not used in a process step, wherein the permanent magnets comprise several permanent magnets that are arranged as a matrix in which poles of the permanent magnets are arranged alternately, and for positioning of magnetic carriers on a plane within the sample volume, the permanent magnets are moved on a spatial axis that is perpendicular to the plane, wherein the permanent magnets lie, relative to the plane, diametrically opposite the magnetic carriers to be positioned, are in a first step moved in the direction of the sample volume and in a second step moved away from the sample volume.

2. The method as claimed in claim 1, wherein the permanent magnets are arranged diametrically opposite relative to the sample volume.

3. The method as claimed in claim 1, wherein the permanent magnets are each arranged in the form of an array.

4. The method as claimed in claim 2, wherein the permanent magnets are each arranged in the form of an array.

5. The method as claimed in claim 1, wherein the sample volume is situated outside the region between the permanent magnets and can be shifted into a region between the permanent magnets.

6. The method as claimed in claim 1, wherein the magnetic carriers are solid phase beads of one of the immunoassays.

7. The method as claimed in claim 1, wherein the magnetic carriers are a solid phase of one of the immunoassays, and the solid phase is moved via the permanent magnets in order to mix the sample volume in one of the immunoassays.

8. The method as claimed in claim 1, further comprising moving other permanent magnets arranged on at least one further spatial axis to mix the magnetic carriers.

9. A method for moving magnetic carriers in a controlled manner for performing immunoassays under weightlessness, comprising: providing a sample volume in a vessel that includes magnetic carriers to perform an immunoassay under weightlessness in which no sedimentation and no convective heat transfer occurs in the sample volume; providing permanent magnets on one spatial axis of the sample volume, the permanent magnets comprise several permanent magnets that are arranged as a matrix in which poles of the permanent magnets are arranged alternately; moving the magnetic carriers within the sample volume by the permanent magnets slidably arranged relative to at least one spatial axis of the sample volume; moving the permanent magnets in phase on the spatial axis of the sample volume to mix the magnetic carriers and the sample volume; and shifting the permanent magnets into a parking position in which a screening device shields the permanent magnets from the sample volume when not used in a process step, wherein for positioning of magnetic carriers on a plane within the sample volume, the permanent magnets are moved on a spatial axis that is perpendicular to the plane, wherein the permanent magnets lie, relative to the plane, diametrically opposite the magnetic carriers to be positioned, are in a first step moved in the direction of the sample volume and in a second step moved away from the sample volume.

Description

(1) The invention and further advantageous embodiments of the invention are explained in more detail below on the basis of diagrams:

(2) FIG. 1 shows an example of a schematic arrangement for performing the method according to the invention in a first application,

(3) FIG. 2 shows an example of a schematic arrangement for performing the method according to the invention in a second application, and

(4) FIG. 3 shows an example of an implementation of a permanent magnet.

(5) FIG. 1 shows an example of a schematic arrangement for mixing magnetic carriers 2 within a sample volume 1. Outside the sample volume 1, permanent magnets 3a and 3b are arranged on one spatial axis x,y,z of the sample volume 1. For clearer representation, only 2 permanent magnets 3 on the spatial axis x are shown in FIG. 1. Of course, further permanent magnets 3a and 3b can be arranged on the other spatial axes y and z.

(6) The two permanent magnets 3a and 3b are arranged diametrically opposite relative to the sample volume 1, i.e. the sample volume 1 can be introduced into a region C between the two permanent magnets 3a and 3b. As is well-known, each permanent magnet 3a and 3b consists of a north pole N and a south pole S. It is advisable that the two permanent magnet 3a and 3b are arranged so that in each case the north and south pole are facing.

(7) FIG. 1 shows the arrangement with the sample volume 1 in a first position A, in which the sample volume 1 is situated outside the region B between the two permanent magnets 3a and 3b. The sample volume 1 can be shifted according to the arrow direction BV into a position B, so that the sample volume 1 is situated in the region C. Of course, it is also possible that the two permanent magnets 3a and 3b are appropriately shifted.

(8) For mixing of the magnetic carriers 2 in the sample volume 1, the sample volume 1 is brought into position B. Next, the two permanent magnets 3a and 3b are moved backwards and forwards in phase according to the arrow direction BM. The magnetic carriers 2 are now alternatingly oriented in the sample volume 1 in accordance with the adjacent magnetic field and correspondingly moved. Through the in-phase backward and forward movement of the two permanent magnets 3a and 3b, thorough mixing of the magnetic carriers 2 in the sample volume 1 is effected.

(9) By appropriate arrangement and movement of other permanent magnets on the spatial axes y and z, the mixing can be improved.

(10) FIG. 2 shows an example of a schematic arrangement for positioning magnetic carriers 2 within a sample volume 1. The diagram shows a sample in position B corresponding to FIG. 1. For positioning of magnetic carriers 2 on the plane 5, the permanent magnet 3a, described below as the positioning permanent magnet, which is arranged on an axis x that is perpendicular to the positioning plane 5, is used. This permanent magnet 3a which relative to the positioning plane lies diametrically opposite the magnetic carriers 2 to be positioned can be shifted in accordance with the arrow directions BM1, BM2.

(11) Another permanent magnet 3b relative to the sample volume 1 arranged diametrically to the positioning permanent magnet 3a on the spatial axis x is shifted into a parking position P and protected by means of a screening device 4, so that magnetic fields of the permanent magnet 3b can have no influence on the magnetic carriers 2 in the sample volume 1.

(12) For positioning the magnetic carriers 2 in the sample volume 1, the positioning permanent magnet 3a is shifted in the direction BM1 of the plane 5. Thereby, the magnetic carriers 2 are oriented and moved in the direction of the plane 5. Next, the positioning permanent magnet 3a is shifted in the direction BM2 and shifted into a corresponding parking position P (not shown).

(13) During use in space, the magnetic carriers remain in this position until the end of the detection, since because of the reduced gravity no sedimentation or thermal convection occurs in the sample volume.

(14) FIG. 3 shows by way of example the implementation of a permanent magnet. The permanent magnets are advantageously implemented as a matrix. The permanent magnet 3a comprises several permanent magnets 30a, which are advantageously arranged as a matrix wherein the permanent magnets 30a are arranged alternately.