JP2014054633A - Device and method for separating magnetic particle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a separator of a magnetic particle capable of generating a magnetic field of various dimensions, by using several predetermined magnetic elements or magnets.SOLUTION: A nonuniform magnetic field generator having an internal space 1 for receiving an object for separating a magnetic particle is a device that has a support structure for the magnets and a plurality of magnets 3 positioned in the support structure, the magnets 3 having a polygonal shape having a plurality of side parts; and forms at least one ring 4 formed of the magnets 3 around the internal space 1 for generating a magnetic field in the internal space 1 such that the number of magnetic poles P becomes an even number larger than 2, the respective magnets 3 having a predetermined magnetization direction 5 in a cross section of a generator and the magnetization direction 5 of the magnets 3 being positioned so as to follow an angular advance of Δy=((P/2)+1)×Δθ (in the cross section of the generator, Δy expresses a variation in the magnetization direction 5 between one magnet 3 and the next magnet 3, Δθ expresses a variation in an angular position between the one magnet 3 and the next magnet 3, and the ring 4 includes the magnets 3 more than the number of magnetic poles P).

Description

  The present invention relates to the field of separation of magnetic particles.

  There are many uses for the separation of different types of particles. For example, in the fields of medicine, biology, and pharmacology, for example, separating a predetermined component (for example, a specific type of antibody) such as a sample, a suspension, or a solution analyzes characteristics regarding these components ( In many cases, for example, to diagnose a disease). Conventionally used methods for separating components, particles or molecules of this kind are separation methods by affinity chromatography and centrifugal precipitation.

  Another method that has been increasingly used in recent years is a separation method based on the use of magnetic particles. This method is a fast and easy method for accurately and reliably separating components such as specific proteins, genetic materials, and biomolecules (for example, biomagnetism published on September 18, 2003). See "Application of magnetic technology in pharmaceutical and biomedical fields" by ZM Said in the 2003 issue of Research and Technology [available at http://www.biomagres.com/content/1/1/2 it can]). This method is based on the use of magnetic particles designed to bind to certain components to be separated from, for example, samples, solutions, suspensions, etc. in some types of containers. By applying a magnetic field, the magnetic particles are separated from the rest of the sample or concentrated in a portion of the container (eg, by an applied magnetic field) and held there. The remainder of the sample (ie at least most of the remainder of the sample) is removed. A cleaning process is then applied to the retained portion. This process may include other separations of magnetic particles and the like.

  U.S. Pat. No. 4,910,148 and international patent application WO-A-02 / 0555206 disclose two separation systems based on magnetic particles. Both systems basically use a magnet associated with the sample to attract the magnetic particles so that they can be separated from the rest of the sample.

There are two types of magnetic particles. The first type is a magnetic particle that is permanently magnetized like a magnet. These particles are characterized by a constant magnetic moment (m) and practically unaffected by external magnetic induction (B). For this type of particle, the force exerted on the particle can be expressed as:

The second type is a particle whose magnetic property changes according to an external magnetic field. For moderate magnetic fields, it can be assumed that the magnetic susceptibility is substantially constant. This class includes soft ferromagnets, paramagnetics, and superparamagnetics. Using this kind of force, the force exerted on such materials can be expressed as:
Here, χ is the magnetic susceptibility and represents the relationship between the external magnetic field and the magnetic moment.

From these descriptions it can be seen that there are at least two ways to improve the effectiveness of the process for separating magnetic particles (by increasing the force exerted on the magnetic particles). That is,
There are methods to increase the magnetic susceptibility and / or magnetic moment, or to generate a large spatial change in the magnetic field.

  Increasing magnetic susceptibility and / or magnetic moment is not dangerous and does not affect other properties of the magnetic particles that are closely related to the biological function of the magnetic particles. However, systems or at least one theoretical system are already known for good and effective separation based on the use of non-uniform magnetic fields in the region of the sample.

  US Pat. No. 6,361,749 discloses a separator in which magnets are distributed between north and south poles. In this separator, the number of magnets is the same as the number of magnetic poles. However, this form has drawbacks. This is because when there are more than four poles, there is virtually no magnetic gradient in the center of the sample and the particles in the center of the sample container do not move to the container wall or move very slowly. (If the four magnetic poles of the four magnets generate a magnetic field, there is a gradient in the middle, but this gradient is distorted in the region near the magnet, as will be explained in more detail below. )

  U.S. Pat. No. 5,705,064 discloses a separator made of a cylinder formed by a ring of magnets. In the cross section of the cylinder, the two side surfaces of each magnet are parallel to and abut the side surfaces of each adjacent magnet. The magnetization direction of these magnets is Δy = 2 × Δθ (where, in the cross section of the cylindrical body, Δy represents the amount of change in the magnetization direction angle between one magnet and the next magnet, and Δθ is According to the angular progression (representing the amount of change in angular position between one magnet and the next magnet) (or alternatively, in the cross section of the cylinder, the angular progression is y = 2 × θ, Where y represents the magnetization direction angle of the magnet with respect to the dipole reference axis and θ is the angular position of the magnet with respect to the dipole reference axis), thus the system forms a magnetic dipole. Thus, a magnetic field that is relatively uniform, i.e. a very small magnetic field gradient, is obtained. This means that it is disadvantageous when trying to separate magnetic particles quickly and effectively (as described above, the force exerted on the particles is increased when the magnetic field gradient is large). Because the speed at which the particles are positioned in one or more regions of the sample or container can be increased).

  US patent application 2003/0015474 discloses another separator based on a cylinder formed of eight magnets. In the cross section of the cylinder, each magnet has two sides that are parallel to and abut the sides of each adjacent magnet. The magnetization direction of the magnet is Δy = 3 × Δθ (where, in the cross section of the cylindrical body, Δy represents the amount of change in the magnetization direction angle between one magnet and the next magnet, and Δθ is one According to the angular progression (or representing the amount of change in angular position between the magnets) (or alternatively, in said section of the cylinder, the angular progression is y = 3 × θ, where , Y represents the magnetization direction angle of the magnet with respect to the dipole reference axis and θ is the angular position of the magnet with respect to the dipole reference axis), thus the system forms a magnetic quadrupole.

  The magnetic particle separator based on the structure disclosed in US Pat. No. 5,705,064 can generate a strong magnetic field, whereas the structure disclosed in US Patent Application Publication No. 2003/0015474 is disclosed. Based separators can generate a substantially constant magnetic field gradient. These structures are based on the Halback Theorem. According to the Halbach theory, when the magnetization of an infinite linear magnet magnetized in the direction perpendicular to the axis is rotated around the axis, the magnetic field module is constant over the space, and all the directions are In the same space at the same angle and in the opposite direction to the direction of rotation. This principle can be used to develop a dipole source that generates a uniform magnetic field inside a cylindrical cavity (see, for example, JMD Coey (author) 1996 Rare Earth Magnets, pages 401- (See “Static Use” by HA Leupold, page 405). Furthermore, a substantially zero magnetic field can be generated outside the cylinder. This is advantageous with regard to safety. These structures are known as “Halbach Cylinders”. This principle is easy to use with multipole sources, and for quadrupole sources, the slope is constant.

  Normally, magnetic particle separators are used to separate magnetic particles of small volume, typically 50 ml or less. However, the technique for separating the magnetic particles is further carried out for technical and / or commercial purposes in larger volumes (samples, solutions, suspensions, etc.), for example on the order of a few liters. In useful applications, it has important applications. The volume to be handled may vary greatly. Therefore, it is useful to be able to easily change the scale of the structure of the system that generates the magnetic field.

  The structures disclosed in US Pat. No. 5,705,064 and US Patent Application Publication No. A-2003 / 0015474 are based on a hullback cylinder. The hullback cylinder includes magnets arranged side by side, and the side surfaces of each magnet are parallel to the side surfaces of adjacent magnets and come into contact with these side surfaces. In both figures, the geometry of the cross-section of the structure that generates the magnetic field of the separator is substantially trapezoidal with a small inside and a large outside, and the magnets that are adjacent on both sides corresponding to the sides of the magnet You can see how this is done by using the magnet that hits the side of the. Thus, the structure for generating a magnetic field has an inner surface having a regular polygonal cross section with a short side and an outer surface having a regular polygonal cross section with a long side.

  Although these structures are theoretically good and have no major technical problems, at least a system for separating magnetic particles in small volumes (applied to containers with volumes of the order of a few ml) is available. If not, it has been found that there are problems in changing the scale and obtaining the components.

  For example, an attempt is made to increase the diameter of the internal space of the cylinder, that is, the diameter of the space in which magnetic particles are separated and receive objects (samples, suspensions, solutions, containers, etc.) that must be exposed to a magnetic field. In some cases, the magnet dimensions must be changed to maintain the design structure described above. In other words, a magnet used in a separator having a free space of a predetermined diameter is at least a hull disclosed in US Pat. No. 5,705,064 and US Patent Application Publication No. 2003/0015474. When maintaining the back cylinder structure, it cannot be used in a structure having a different internal free space. Further, when the size of the magnet is increased, it becomes increasingly difficult to position the magnet with the structure disclosed in US Pat. No. 5,705,064 and US Patent Application Publication No. 2003/0015474. This is because the repulsive force between the magnets increases.

On the other hand, it can be seen how the relationship between the magnet geometry in the cross-section of the structure and the magnetization direction can be changed between the various magnets (as seen in the cross-section of the structure). For example, in US Patent Application Publication No. 2003/0015474, there are at least three types of relationships between magnetization and magnet geometry. That is,
-In two of the plurality of magnets, the magnetization direction (S → N) is from the large side (outside) to the small side (inside),
-In two of the plurality of magnets, the magnetization direction (S → N) is from a small side (inside) to a large side (outside),
-In four of the magnets, the magnetization direction (S → N) is substantially parallel to the large and small sides (in two of these magnets, the magnetization direction is viewed from the outside; From left to right and the other two in the opposite direction).

  This means, for example, that at least three types of magnets must be used to form the structure according to US 2003/0015474. The type of magnetic element used in this type of magnet has a preferred or easy magnetization direction (corresponding to the “easy axis” of the magnetic), and these three different types of magnets In order to obtain, it is necessary to machine the original magnetic body based on three different templates. Theoretically, this creates a more complex and expensive structure. This is particularly a problem when manufacturing a small series of separators, and often occurs when trying to manufacture separators that are specifically designed for specific customer and / or application requirements.

U.S. Pat. No. 4,910,148 International patent application WO-A-02 / 0555206 US Pat. No. 6,361,749 US Pat. No. 5,705,064 US Patent Application Publication No. 2003/0015474

  For the above reasons, it is desirable to provide a magnetic particle separator with a structure that can be scaled, and more particularly, several predetermined magnetic elements or magnets are used to generate magnetic fields of various dimensions. It is desirable to provide a structure for

  A first aspect of the present invention relates to a device for separating magnetic particles comprising a non-uniform magnetic field generator having a cross section with an internal space for receiving an object to be subjected to a magnetic particle separation process.

The generator has a support structure for the magnet and a plurality of magnets positioned on the support structure. The magnet has a polygonal shape with a plurality of sides in a cross section of the generator along a plane containing the plurality of magnets. (These magnets may also be elliptical or circular.
This is because, for example, a circle can be considered as a polygon with an infinite number of sides). The magnets are arranged at an angle and form at least one ring of magnets around the interior space. This is because P magnetic poles generate a magnetic field in the internal space.
Here, P is an even number greater than 2.

  Each magnet has a predetermined magnetization direction in the cross section of the generator. The magnets of the at least one ring are positioned such that the magnetization direction of the magnet follows an angular progression of Δy = ((P / 2) +1) × Δθ. Here, in the cross section of the generator, Δy represents the amount of change in the magnetization direction between one magnet and the next magnet, and Δθ is the change in angular position between one magnet and the next magnet. Represents the quantity (and P is the number of magnetic poles mentioned above).

  The at least one ring includes more than P magnets (ie, more magnets than the number of magnetic field poles). In this way, a magnetic field having a large magnetic gradient and a substantially constant magnetic field can be obtained over the internal space, and as already known, distortion in the distribution of the magnetic field increases as the number of magnets increases. (E.g. if only 4 magnets are used, gradient "distortion" occurs near the magnets, but if a very large number of magnets are used, the gradient Is practically perfect, i.e. substantially free of strain except in areas very close to the surface of the magnet).

  According to this aspect of the invention, N types of magnets are provided in the generator cross section. The various magnets have a predetermined geometric shape in the cross section of the generator, and there is a predetermined relationship between the magnetization direction and the geometric shape. According to this aspect of the invention, N = 1 or N = 2.

  This means that by using one type of magnet, or at most two types of magnets each having its own geometric shape and magnetization direction / geometric shape relationship, there are few types (one type or two types). This is advantageous because a magnet can provide great flexibility. This is also theoretically advantageous and is particularly important when producing a small series of separators. According to the present invention, separators of various sizes and characteristics can be manufactured using only one type of magnet or using two types of magnets. This can be done, for example, using one or more templates (taking into account the preferred magnetization direction of the magnetic material) and producing a separator based on magnets obtained from the cut magnetic material. It means that.

  The generator can be formed such that, in the cross section of the generator, the sides of the magnet do not come into contact with the magnets that are angularly arranged back and forth in the ring (but the magnets are in contact with each other). And may be formed of several magnet pieces whose surfaces hit each other). By distributing the magnets in this way, great structural flexibility is obtained, so that the same magnet can be used using magnets with simple geometric shapes without changing the shape or dimensions of the magnets. Can be used to form structures of various dimensions. According to this form of the invention, the magnets forming the ring are, for example, not in contact with each other or corresponding contact points only with the corners between the two sides of at least one of the magnets. However, it may be in contact with other magnets of the ring (at the corners or sides of another magnet).

  Another aspect of the invention relates to a device for separating magnetic particles comprising a non-uniform magnetic field generator having a cross section with an internal space for receiving an object to be subjected to a magnetic particle separation process.

  The generator has a support structure for a magnet and a plurality of magnets positioned on the support structure, the magnet having a plurality of cross sections of the generator along a plane including the plurality of magnets. It has a polygonal shape with side parts (These magnets may also be elliptical or circular. For example, a circle can be considered a polygon with an infinite number of side parts. For).

  The magnets are arranged at an angle, and at least one ring made of magnets is formed around the inner space in order to generate a magnetic field with P magnetic poles in the inner space. P is an even number of 2 or more.

  Each magnet has a predetermined magnetization direction in the cross section of the generator, and the magnets of the at least one ring are positioned such that the magnetization direction of the magnet follows Δy = ((P / 2) +1) × Δθ . Here, in the cross section of the generator, Δy represents the amount of change in the magnetization direction between one magnet and the next magnet, and Δθ is the change in angular position between one magnet and the next magnet. Represents an amount. The at least one ring comprises more than P magnets (ie more magnets than the number of magnetic poles of the generated magnetic field. In this way, the magnetic gradient is large over the interior space. A substantially constant magnetic field can be obtained, as already known, as the number of magnets increases, the distortion in the magnetic field distribution decreases in the region closest to the magnetic field source. If there are only four, a large “strain” of the magnetic gradient will occur near the magnet, but when multiple magnets are used, the magnetic gradient will include a region very close to the surface of the magnet, Such a large distortion does not occur).

  According to this aspect of the present invention, the generator is formed such that, in the cross section of the generator, the side of the magnet does not contact the side of the magnet that is angularly arranged back and forth in the ring. (However, each magnet may be formed of several magnet pieces arranged with their surfaces facing each other).

This configuration provides great flexibility at the time of designing the magnet structure, which allows one type of magnet (or at least a small number of magnets) to be used to form structures of various dimensions.
Many different magnet configurations without having to change the magnet shape or dimensions, or the magnetization direction with respect to the magnet geometry, because the magnets are not in contact with each other or at least the surfaces of these magnets do not touch each other Can be obtained.

  The magnets forming the ring are, for example, not in contact with each other or if there is some contact between two angularly continuous magnets in the ring, Corresponds to the corner between the two sides of at least one magnet (it hits the corner or side of another magnet).

  For example, N types of magnets may be provided in the cross section of the generator. Each type of magnet has a predetermined geometric shape in the cross section of the generator, and there is a predetermined relationship between the magnetization direction and the geometric shape, N = 1 or N = 2. By using one type of magnet, or at most two types of magnets each having a unique geometric shape and magnetization direction / geometric shape relationship, great flexibility can be obtained with fewer types of magnets. This is advantageous from a theoretical point of view and is particularly important when producing a product for a specific purpose, which makes it very even when only one or two magnets are to be used. Separators with various sizes and characteristics can be formed, and all magnets can be obtained from cut magnetic bodies using one or two templates.

  Either of the two aspects of the invention described above can be implemented in accordance with many aspects. For example, in cross section, the magnet may have a substantially rectangular or hexagonal polygonal shape.

  Another aspect of the invention relates to a device for separating magnetic particles, the device comprising a non-uniform magnetic field generator having a cross-section with an interior space for receiving an object that has to undergo a magnetic particle separation process. ing. The generator includes a magnet support structure and a plurality of magnets positioned on the support structure. The magnet has a polygonal shape having a plurality of side portions in a cross section of the generator along a plane including the plurality of magnets. The plurality of magnets are arranged at an angle, and in order to generate a magnetic field with P magnetic poles in the internal space, at least one ring made of magnets is formed around the internal space. P is an even number greater than 2.

  According to this aspect of the invention, the polygonal shape is a hexagonal shape. The hexagonal shape is very useful because it can provide a structure that can be easily scaled using several types of relationships between the magnetizing direction of the magnet and the geometric shape. This provides advantages (see description above). This structure can be easily scaled by removing, for example, a single ring made of magnets. Such a structure made of magnets that can be easily changed in scale, i.e., a structure having an internal space that can be easily expanded, is such that the magnets are brought into contact with each other with the sides of the magnets in contact with the sides of the adjacent magnets. It can be formed by making it into a shape such as a honeycomb.

  Each magnet has a predetermined magnetization direction in the cross section of the generator, and the magnets of the at least one ring have an angle progression of Δy = ((P / 2) +1) × Δθ. Can be positioned to follow. Here, in the cross section of the generator, Δy represents the amount of change in the magnetization direction between one magnet and the next magnet, and Δθ is the change in angular position between one magnet and the next magnet. Represents an amount.

  The at least one ring may comprise more than P magnets (ie, the number of magnets may be greater than the number of magnetic poles in the magnetic field). In this way, a magnetic field having a constant magnetic gradient can be formed in the internal space when P = 4 (if P> 4, the gradient is not constant. For example, when P = 6, the gradient is linear. To zero in the middle, which means that the effectiveness of the separation is low). By using more magnets than the number of poles of the magnetic field, a magnetic field with a large magnetic gradient over the interior space and a substantially constant magnetic field can be obtained. As is well known, as the number of magnets increases, the distortion in the magnetic field contour decreases in the region closest to the magnetic field source (eg, if only four magnets are used, the gradient “distortion nearer to the magnets). However, if a very large number of magnets are used, the gradient is practically perfect, i.e. there is virtually no distortion except in areas very close to the surface of the magnet).

  In the cross section of the generator, N types of magnets are provided. Each type of magnet has a predetermined geometric shape in the cross section of the generator, and there is a predetermined relationship between their magnetization direction and said geometric shape. N is, for example, 1 or 2. By using one type of magnet, or at most two types of magnets with unique geometric shape and magnetization direction / geometric relationship, provide great flexibility and reduce the number of magnet types . This is very good in theory and is particularly important in producing a small series of products. According to the present invention, separators with very different sizes and characteristics can be formed using only one type of magnet or using two types of magnets.

  The generator can be formed such that, in cross-section, the sides of the magnet do not hit the sides of the magnet that are angularly front and back in the ring (but each magnet hits the surface against each other). It may be made up of several magnet pieces). This provides great flexibility in structure, so that various dimensions can be formed using the same magnet or multiple types of magnets without changing the shape or dimensions of the magnet. According to this aspect of the invention, the magnets forming the ring are not in contact with each other, or some or all of the magnets are in contact, but the contact between two angularly continuous magnets in the ring. However, the magnet may be arranged so as to correspond to one corner between two sides of at least one of the magnets and to hit another corner or side of another magnet.

  Any of the aspects of the invention described above may be formed according to various forms including some or all of the following optional features.

  In cross-section, the magnets that make up the magnet ring may have a geometrical direction that follows an angular progression of Δy = ((P / 2) +1) × Δθ. Here, in the cross section of the generator, Δy represents the change in the angular direction of the geometric shape between one magnet and the next magnet, and Δθ is between one magnet and the next magnet. Represents the change in angular position. In other words, the magnets are arranged to change the angular direction of the magnet geometry rather than changing the magnetization direction with respect to the geometry. This is advantageous because the original magnetic material can be cut using a single template, i.e., parts with the same relationship between magnetization and geometry can be produced.

  The number P of magnetic poles may be four. This provides a large constant gradient in the magnetic field across the internal space.

  The magnet forms an equilateral polygonal shape in the cross section of the generator along the plane including the plurality of magnets.

  The magnet may be a parallelepiped.

  In cross section, the magnets may be arranged in a form that includes a plurality of concentric rings made of magnets.

  The structure may include a plurality of magnet rings arranged along the longitudinal axis of the device substantially perpendicular to the cross section.

  One or more magnets may have at least two magnet pieces arranged side by side.

  The support structure may have a plurality of support members (eg, members in the form of an aluminum ring) positioned one after the other along the longitudinal axis of the device. Each support member is provided with a plurality of geometrically shaped holes for receiving the magnets, matching the geometric shape of the magnets.

  The magnet may be made of, for example, NdFeB, SmCo, Ni, or more generally a magnetic anisotropy, eg a magnetocrystalline anisotropy magnet (having this property). Otherwise, there is a risk that the magnet will demagnetize due to the magnetic field generated by the adjacent magnet, which occurs when the material is steel or AlNiCo).

  Another aspect of the invention relates to a method for separating magnetic particles of a subject (eg, a container containing a fluid, eg, a suspension of magnetic particles). According to this aspect of the invention, the method includes placing an object in the interior space of any of the devices described above.

  For the purpose of illustrating and better understanding the features of the present invention according to preferred examples of its actual embodiments, a set of drawings is presented in an illustrative, non-limiting manner as an integral part of the above description.

1 is a schematic perspective view of a support structure for a separator according to an embodiment of the present invention. FIG. 1 is a cross-sectional view of a separator according to an embodiment of the present invention. FIG. 6 is a schematic view of the orientation of magnets and the magnetization directions of these magnets in a cross section of a separator according to another embodiment of the invention. FIG. 6 is a schematic view of the orientation of magnets and the magnetization directions of these magnets in a cross section of a separator according to another embodiment of the invention. 1 is a perspective view of a support structure in an assembled state according to an embodiment of the present invention. FIG. FIG. 6 is a perspective view of a support structure in another assembled state according to an embodiment of the present invention. FIG. 6 is a schematic diagram illustrating the configuration of a magnet structure in cross-section of a separator of an embodiment, with a hexagonal magnet. FIG. 6 is a schematic diagram showing the form of the structure of a magnet in a cross section of another embodiment of a separator by a hexagonal magnet. FIG. 6 is a schematic view showing a configuration of a magnet structure in a cross-section of a separator according to still another embodiment using a hexagonal magnet. FIG. 6 is a perspective view of a separator in a completed state according to an embodiment of the present invention.

  FIG. 1 is a schematic view of one preferred embodiment of the present invention, and more particularly, a plurality of, for example, aluminum, schematically shown as rings 21, 22, 23 disposed on a support or base 24. FIG. 1 shows a support structure 2 including a support ring. The free space 1 in the ring is a place for receiving a sample, i.e., an object, on which magnetic particle separation processing is performed.

  As can be seen from the ring 21 (the form of this ring is the same as or substantially the same as the other rings 22 and 23), the support ring has a series of holes or channels 2B where magnets Is housed so as not to move regardless of the attractive or repulsive force exerted between these magnets. The illustrated structure may further be provided with a cover (not shown) that prevents the magnet from moving vertically (ie, parallel to the longitudinal axis of the support structure). FIG. 1 further shows a hole 2A. In these holes 2A are positioned several bars made of brass or stainless steel that are used to keep the ring joined. Basically, these bars together with the aluminum rings 21, 22, 23, the base 24 and a cover (not shown) form a support structure.

  Position the magnet in the channel or hole 2B. Each magnet has two or more magnet pieces that are arranged side by side to form a magnet. The cross section of the magnet coincides with the cross section of the hole or channel 2B, so that the magnet is held in the hole with no play or with a very limited amount of play.

  FIG. 2 shows a support structure 2 of the type shown in FIG. 1 using a plurality of bars 25 made of brass or the like passed through a support ring of the structure, and a plurality of magnets 3 each having a plurality of sides. Schematically shows a method of accommodating the in the hole 2B. In particular, FIG. 2 shows a cross section of the separator, in which the magnet 3 has a polygonal cross section, in detail a rectangular shape or in more detail a square shape. You can see that The magnets are not in contact with each other. In particular, there is no magnet with the sides or surfaces 3a, 3b, 3c, and 3d placed against the surface or side of an adjacent magnet (but without exceeding the scope of the present invention Can be in contact with the corners or sides of adjacent magnets). As can be seen from FIG. 2, the magnets 3 are arranged to form a ring 4 made of magnets, and the fact that the sides of these magnets do not have to touch each other means that one magnet and It means that the magnetization direction can be changed with the next magnet. This is done by adapting the relationship between the magnet and the physical parts that make up the support structure, and the relationship between the magnetization direction (in the cross section of the separator) and the geometry will vary. There is no need to use magnet pieces.

  This concept will be more easily understood by looking at FIG. 3, which shows the distribution of magnets 3 in the cross section of the separator in an embodiment of the invention. As can be seen, the arrows indicating the direction, ie the direction of magnetization 5, have the same relationship for all magnets with respect to the magnet geometry in the plane of the cross section of the separator.

  In detail, the magnetization direction of all magnets is parallel to the two sides of the magnets and perpendicular to the other two sides. This means that, based on the same template, a piece of magnetic material is parallel and perpendicular to the direction in which the material is easily magnetized (ie, the direction that coincides with the so-called “easy axis” of the material). It means that all the magnets can be obtained by cutting into two.

As shown in FIG. 3 which shows the distribution of the magnets 3 that generate the magnetic fields of four poles in the internal space of the separator, the magnetization direction 5 of the magnets 3 of the magnet ring 4 advances at an angle of Y = 3 × Δθ ( Follow angular progression). Here, ΔY represents the change in the magnetization direction 5 between a certain magnet 3 and the next magnet in the cross section of the generator, and Δθ represents the change in the angular position between the certain magnet 3 and the next magnet. Represent. However, according to the present invention, this is not done by changing the magnetization direction of the magnet with respect to the magnet geometry, but by changing the direction of the magnet geometry with respect to the support structure. Done. Specifically, as can be seen from FIG. 3, the direction of the geometric shape of the magnet 3 forming the magnet ring 4 follows an angular progression of ΔY = 3Δθ. Here, in the cross section of the separator, ΔY represents the amount of change in the angular direction 5 of the geometric shape between a certain magnet 3 and the next magnet, and Δθ represents the difference between the certain magnet and the next magnet. Represents the amount of change in angular position.
In other words, since it is not necessary to apply the side part of the magnet to the side part of the adjacent magnet, the angle of the magnetization direction can be advanced in accordance with the progress of the angle in the direction of the physical elements constituting the magnet.

  In the form as shown in FIG. 3, the induction module of the generated magnetic field (B) increases rapidly and from the zero induction at the center of the ring 4 (ie the center of the internal free space 1), the edge (of the magnet ring). Changes to high induction at (near) and the slope is substantially constant, typically several T / m. Due to this constant gradient, the magnetic particles in the sample introduced into the internal space, specifically, for example, in the sample that occupies most of the internal space in the cross section of the separator, move toward the wall of the container. To do. In FIG. 3, the arrows in the “inner space” 1 surrounded by the ring 4 indicate the magnetization gradient and thus the direction of the force exerted on the magnetic particles in the sample, whereby the magnetic particles contain the sample. Move towards the wall of the container. The nearly circular line in FIG. 3 shows the equipotential line, that is, the line formed by the points with the same magnetic field strength value (this also applies to other figures showing this kind of line and arrow). ).

  FIG. 4 shows a magnet distribution according to another embodiment of the present invention. In this embodiment, the magnet 3 is divided and distributed into two rings, and the angular progression of the magnetization direction 5 is the same as that shown in FIG. 3, but in this case, one ring has 22 magnets. Use two rings made of magnets, with the other outer ring containing 30 magnets, use the same kind of magnets as in the configuration of FIG. 3, and have a relatively large magnetic field gradient .

  FIG. 5 illustrates a support structure during assembly according to a preferred embodiment of the present invention. In detail, it can be seen how the three rings 21, 22, 23 made of, for example, aluminum having a height of about 10 mm are fixed to the base plate 24. These rings can be produced, for example, by cutting a 10 mm thick aluminum plate with a laser.

  The rings are secured to each other by a securing system that includes bars 25 made of, for example, brass or non-magnetic stainless steel. The bar 25 is provided with a thread, and the aluminum ring is fixed to a desired height by using, for example, a plastic bolt 26. A method of forming each magnet 3 with two parts 31 and 32 that are combined to form the magnet 3 is schematically shown.

FIG. 6 shows another assembly process for the separator with the addition of another aluminum ring 20.
In this figure, all the magnets 3 are incorporated, and each magnet 3 includes two parts 31 and 32. The structure shown in FIG. 6 has three magnet layers. The magnet may be an NdFeB magnet, for example, or it may be made of any other suitable material depending on the particular property to be obtained.

  FIG. 7 schematically illustrates another embodiment of the present invention. In this embodiment, a hexagonal cross-section magnet 3 arranged in a ring shape around the inner space 1 that receives the sample or object to be processed is used. In this form, the angle of the magnetization direction 5 can be appropriately advanced by using a magnet having a hexagonal cross section. A single relationship is formed between the direction of magnetization and the cross-sectional geometry of the magnet, while at the same time the magnet faces side-to-side (ie, two magnets adjacent to each other) Can be placed on each side). This provides a structural advantage.

  FIG. 8 shows another configuration based on two rings, an inner ring and an outer ring made of hexagonal magnets. All of the magnets contact the sides of the magnets of the same and another ring that are adjacent. In this case, all the magnets have the same geometric shape, but there are two kinds of relationship between magnetization and geometric shape. It will be appreciated that the magnetization direction 5 of one magnet 3A is perpendicular to the two surfaces of the magnet and the magnetization direction of the other magnet 3B moves towards the edge between the two surfaces.

  FIG. 9 shows another form of a magnet having a hexagonal cross section. The internal space 1 shows the direction of the magnetic gradient (with arrows) and several equipotential lines, i.e. lines formed at the same point in the value of the magnetic field cross-section strength.

  As can be easily seen from these figures, the shape of the “honeycomb shape” including various “rings” made of hexagonal magnets has a great advantage because it allows designing a system that can be easily scaled. For example, in order to increase the diameter of the inner space 1 of the separator having the shape shown in FIG. 8, the magnet 6 such as the inner ring can be easily eliminated.

FIG. 10 shows the separator based on the design shown in FIGS. 5 and 6 in the completed state.
The separator is provided with an outer cover 29 and a cover 27, and the cover 27 is fixed to the bar 25 (not shown in FIG. 10) with screws 28.

  In this specification, terms such as “comprises” (such as “comprising”) should not be construed as exclusive. That is, it does not exclude that the described element includes other components, processes, and the like.

  Further, the present invention is not limited to the specific embodiments described above, for example, modifications (e.g., materials, dimensions, components, configurations) by those skilled in the art within the scope of the claims. , Etc.).

  The present invention relates to the field of separation of magnetic particles.

  There are many uses for the separation of different types of particles. For example, in the fields of medicine, biology, and pharmacology, for example, separating a predetermined component (for example, a specific type of antibody) such as a sample, a suspension, or a solution analyzes characteristics regarding these components ( In many cases, for example, to diagnose a disease). Conventionally used methods for separating components, particles or molecules of this kind are separation methods by affinity chromatography and centrifugal precipitation.

  Another method that has been increasingly used in recent years is a separation method based on the use of magnetic particles. This method is a fast and easy method for accurately and reliably separating components such as specific proteins, genetic materials, and biomolecules (for example, biomagnetism published on September 18, 2003). See "Application of magnetic technology in pharmaceutical and biomedical fields" by ZM Said in the 2003 issue of Research and Technology [available at http://www.biomagres.com/content/1/1/2 it can]). This method is based on the use of magnetic particles designed to bind to certain components to be separated from, for example, samples, solutions, suspensions, etc. in some types of containers. By applying a magnetic field, the magnetic particles are separated from the rest of the sample or concentrated in a portion of the container (eg, by an applied magnetic field) and held there. The remainder of the sample (ie at least most of the remainder of the sample) is removed. A cleaning process is then applied to the retained portion. This process may include other separations of magnetic particles and the like.

  U.S. Pat. No. 4,910,148 and international patent application WO-A-02 / 0555206 disclose two separation systems based on magnetic particles. Both systems basically use a magnet associated with the sample to attract the magnetic particles so that they can be separated from the rest of the sample.

There are two types of magnetic particles. The first type is a magnetic particle that is permanently magnetized like a magnet. These particles are characterized by a constant magnetic moment (m) and practically unaffected by external magnetic induction (B). For this type of particle, the force exerted on the particle can be expressed as:

The second type is a particle whose magnetic property changes according to an external magnetic field. For moderate magnetic fields, it can be assumed that the magnetic susceptibility is substantially constant. This class includes soft ferromagnets, paramagnetics, and superparamagnetics. Using this kind of force, the force exerted on such materials can be expressed as:
Here, χ is the magnetic susceptibility and represents the relationship between the external magnetic field and the magnetic moment.

From these descriptions it can be seen that there are at least two ways to improve the effectiveness of the process for separating magnetic particles (by increasing the force exerted on the magnetic particles). That is,
There are methods to increase the magnetic susceptibility and / or magnetic moment, or to generate a large spatial change in the magnetic field.

  Increasing magnetic susceptibility and / or magnetic moment is not dangerous and does not affect other properties of the magnetic particles that are closely related to the biological function of the magnetic particles. However, systems or at least one theoretical system are already known for good and effective separation based on the use of non-uniform magnetic fields in the region of the sample.

  US Pat. No. 6,361,749 discloses a separator in which magnets are distributed between north and south poles. In this separator, the number of magnets is the same as the number of magnetic poles. However, this form has drawbacks. This is because when there are more than four poles, there is virtually no magnetic gradient in the center of the sample and the particles in the center of the sample container do not move to the container wall or move very slowly. (If the four magnetic poles of the four magnets generate a magnetic field, there is a gradient in the middle, but this gradient is distorted in the region near the magnet, as will be explained in more detail below. )

  U.S. Pat. No. 5,705,064 discloses a separator made of a cylinder formed by a ring of magnets. In the cross section of the cylinder, the two side surfaces of each magnet are parallel to and abut the side surfaces of each adjacent magnet. The magnetization direction of these magnets is Δy = 2 × Δθ (where, in the cross section of the cylindrical body, Δy represents the amount of change in the magnetization direction angle between one magnet and the next magnet, and Δθ is According to the angular progression (representing the amount of change in angular position between one magnet and the next magnet) (or alternatively, in the cross section of the cylinder, the angular progression is y = 2 × θ, Where y represents the magnetization direction angle of the magnet with respect to the dipole reference axis and θ is the angular position of the magnet with respect to the dipole reference axis), thus the system forms a magnetic dipole. Thus, a magnetic field that is relatively uniform, i.e. a very small magnetic field gradient, is obtained. This means that it is disadvantageous when trying to separate magnetic particles quickly and effectively (as described above, the force exerted on the particles is increased when the magnetic field gradient is large). Because the speed at which the particles are positioned in one or more regions of the sample or container can be increased).

  US patent application 2003/0015474 discloses another separator based on a cylinder formed of eight magnets. In the cross section of the cylinder, each magnet has two sides that are parallel to and abut the sides of each adjacent magnet. The magnetization direction of the magnet is Δy = 3 × Δθ (where, in the cross section of the cylindrical body, Δy represents the amount of change in the magnetization direction angle between one magnet and the next magnet, and Δθ is one According to the angular progression (or representing the amount of change in angular position between the magnets) (or alternatively, in said section of the cylinder, the angular progression is y = 3 × θ, where , Y represents the magnetization direction angle of the magnet with respect to the dipole reference axis and θ is the angular position of the magnet with respect to the dipole reference axis), thus the system forms a magnetic quadrupole.

  The magnetic particle separator based on the structure disclosed in US Pat. No. 5,705,064 can generate a strong magnetic field, whereas the structure disclosed in US Patent Application Publication No. 2003/0015474 is disclosed. Based separators can generate a substantially constant magnetic field gradient. These structures are based on the Halback Theorem. According to the Halbach theory, when the magnetization of an infinite linear magnet magnetized in the direction perpendicular to the axis is rotated around the axis, the magnetic field module is constant over the space, and all the directions are In the same space at the same angle and in the opposite direction to the direction of rotation. This principle can be used to develop a dipole source that generates a uniform magnetic field inside a cylindrical cavity (see, for example, JMD Coey (author) 1996 Rare Earth Magnets, pages 401- (See “Static Use” by HA Leupold, page 405). Furthermore, a substantially zero magnetic field can be generated outside the cylinder. This is advantageous with regard to safety. These structures are known as “Halbach Cylinders”. This principle is easy to use with multipole sources, and for quadrupole sources, the slope is constant.

  Normally, magnetic particle separators are used to separate magnetic particles of small volume, typically 50 ml or less. However, the technique for separating the magnetic particles is further carried out for technical and / or commercial purposes in larger volumes (samples, solutions, suspensions, etc.), for example on the order of a few liters. In useful applications, it has important applications. The volume to be handled may vary greatly. Therefore, it is useful to be able to easily change the scale of the structure of the system that generates the magnetic field.

  The structures disclosed in US Pat. No. 5,705,064 and US Patent Application Publication No. A-2003 / 0015474 are based on a hullback cylinder. The hullback cylinder includes magnets arranged side by side, and the side surfaces of each magnet are parallel to the side surfaces of adjacent magnets and come into contact with these side surfaces. In both figures, the geometry of the cross-section of the structure that generates the magnetic field of the separator is substantially trapezoidal with a small inside and a large outside, and the magnets that are adjacent on both sides corresponding to the sides of the magnet You can see how this is done by using the magnet that hits the side of the. Thus, the structure for generating a magnetic field has an inner surface having a regular polygonal cross section with a short side and an outer surface having a regular polygonal cross section with a long side.

  Although these structures are theoretically good and have no major technical problems, at least a system for separating magnetic particles in small volumes (applied to containers with volumes of the order of a few ml) is available. If not, it has been found that there are problems in changing the scale and obtaining the components.

  For example, an attempt is made to increase the diameter of the internal space of the cylinder, that is, the diameter of the space in which magnetic particles are separated and receive objects (samples, suspensions, solutions, containers, etc.) that must be exposed to a magnetic field. In some cases, the magnet dimensions must be changed to maintain the design structure described above. In other words, a magnet used in a separator having a free space of a predetermined diameter is at least a hull disclosed in US Pat. No. 5,705,064 and US Patent Application Publication No. 2003/0015474. When maintaining the back cylinder structure, it cannot be used in a structure having a different internal free space. Further, when the size of the magnet is increased, it becomes increasingly difficult to position the magnet with the structure disclosed in US Pat. No. 5,705,064 and US Patent Application Publication No. 2003/0015474. This is because the repulsive force between the magnets increases.

On the other hand, it can be seen how the relationship between the magnet geometry in the cross-section of the structure and the magnetization direction can be changed between the various magnets (as seen in the cross-section of the structure). For example, in US Patent Application Publication No. 2003/0015474, there are at least three types of relationships between magnetization and magnet geometry. That is,
-In two of the plurality of magnets, the magnetization direction (S → N) is from the large side (outside) to the small side (inside),
-In two of the plurality of magnets, the magnetization direction (S → N) is from a small side (inside) to a large side (outside),
-In four of the magnets, the magnetization direction (S → N) is substantially parallel to the large and small sides (in two of these magnets, the magnetization direction is viewed from the outside; From left to right and the other two in the opposite direction).

This means, for example, that at least three types of magnets must be used to form the structure according to US 2003/0015474. The type of magnetic element used in this type of magnet has a preferred or easy magnetization direction (corresponding to the “easy axis” of the magnetic), and these three different types of magnets In order to obtain, it is necessary to machine the original magnetic body based on three different templates. Theoretically, this creates a more complex and expensive structure. This is particularly a problem when manufacturing a small series of separators, and often occurs when trying to manufacture separators that are specifically designed for specific customer and / or application requirements.
U.S. Pat. No. 4,910,148 International patent application WO-A-02 / 0555206 US Pat. No. 6,361,749 US Pat. No. 5,705,064 US Patent Application Publication No. 2003/0015474

  For the above reasons, it is desirable to provide a magnetic particle separator with a structure that can be scaled, and more particularly, several predetermined magnetic elements or magnets are used to generate magnetic fields of various dimensions. It is desirable to provide a structure for

  A first aspect of the present invention relates to a device for separating magnetic particles comprising a non-uniform magnetic field generator having a cross section with an internal space for receiving an object to be subjected to a magnetic particle separation process.

  The generator has a support structure for the magnet and a plurality of magnets positioned on the support structure. The magnet has a polygonal shape with a plurality of sides in a cross section of the generator along a plane containing the plurality of magnets. (These magnets may also be elliptical or circular because, for example, a circle can be considered a polygon with an infinite number of sides). The magnets are arranged at an angle and form at least one ring of magnets around the interior space. This is because P magnetic poles generate a magnetic field in the internal space. Here, P is an even number greater than 2.

  Each magnet has a predetermined magnetization direction in the cross section of the generator. The magnets of the at least one ring are positioned such that the magnetization direction of the magnet follows an angular progression of Δy = ((P / 2) +1) × Δθ. Here, in the cross section of the generator, Δy represents the amount of change in the magnetization direction between one magnet and the next magnet, and Δθ is the change in angular position between one magnet and the next magnet. Represents the quantity (and P is the number of magnetic poles mentioned above).

  The at least one ring includes more than P magnets (ie, more magnets than the number of magnetic field poles). In this way, a magnetic field having a large magnetic gradient and a substantially constant magnetic field can be obtained over the internal space, and as already known, distortion in the distribution of the magnetic field increases as the number of magnets increases. (E.g. if only 4 magnets are used, gradient "distortion" occurs near the magnets, but if a very large number of magnets are used, the gradient Is practically perfect, i.e. substantially free of strain except in areas very close to the surface of the magnet).

According to the onset bright, N types of magnets are provided in the cross-section of the generator. The various magnets have a predetermined geometric shape in the cross section of the generator, and there is a predetermined relationship between the magnetization direction and the geometric shape. According to the onset bright, it is N = 1 or N = 2.

  This means that by using one type of magnet, or at most two types of magnets each having its own geometric shape and magnetization direction / geometric shape relationship, there are few types (one type or two types). This is advantageous because a magnet can provide great flexibility. This is also theoretically advantageous and is particularly important when producing a small series of separators. According to the present invention, separators of various sizes and characteristics can be manufactured using only one type of magnet or using two types of magnets. This can be done, for example, using one or more templates (taking into account the preferred magnetization direction of the magnetic material) and producing a separator based on magnets obtained from the cut magnetic material. It means that.

  The generator can be formed such that, in the cross section of the generator, the sides of the magnet do not come into contact with the magnets that are angularly arranged back and forth in the ring (but the magnets are in contact with each other). And may be formed of several magnet pieces whose surfaces hit each other). By distributing the magnets in this way, great structural flexibility is obtained, so that the same magnet can be used using magnets with simple geometric shapes without changing the shape or dimensions of the magnets. Can be used to form structures of various dimensions. According to this form of the invention, the magnets forming the ring are, for example, not in contact with each other or corresponding contact points only with the corners between the two sides of at least one of the magnets. However, it may be in contact with other magnets of the ring (at the corners or sides of another magnet).

  Another aspect of the invention relates to a device for separating magnetic particles comprising a non-uniform magnetic field generator having a cross section with an internal space for receiving an object to be subjected to a magnetic particle separation process.

  The generator has a support structure for a magnet and a plurality of magnets positioned on the support structure, the magnet having a plurality of cross sections of the generator along a plane including the plurality of magnets. It has a polygonal shape with side parts (These magnets may also be elliptical or circular. For example, a circle can be considered a polygon with an infinite number of side parts. Because).

  The magnets are arranged at an angle, and at least one ring made of magnets is formed around the inner space in order to generate a magnetic field with P magnetic poles in the inner space. P is an even number of 2 or more.

  Each magnet has a predetermined magnetization direction in the cross section of the generator, and the magnets of the at least one ring are positioned such that the magnetization direction of the magnet follows Δy = ((P / 2) +1) × Δθ . Here, in the cross section of the generator, Δy represents the amount of change in the magnetization direction between one magnet and the next magnet, and Δθ is the change in angular position between one magnet and the next magnet. Represents an amount. The at least one ring comprises more than P magnets (ie more magnets than the number of magnetic poles of the generated magnetic field. In this way, the magnetic gradient is large over the interior space. A substantially constant magnetic field can be obtained, as already known, as the number of magnets increases, the distortion in the magnetic field distribution decreases in the region closest to the magnetic field source. If there are only four, a large “strain” of the magnetic gradient will occur near the magnet, but when multiple magnets are used, the magnetic gradient will include a region very close to the surface of the magnet, Such a large distortion does not occur).

  According to this aspect of the present invention, the generator is formed such that, in the cross section of the generator, the side of the magnet does not contact the side of the magnet that is angularly arranged back and forth in the ring. (However, each magnet may be formed of several magnet pieces arranged with their surfaces facing each other).

  This configuration provides great flexibility at the time of designing the magnet structure, which allows one type of magnet (or at least a small number of magnets) to be used to form structures of various dimensions. Many different magnet configurations without having to change the magnet shape or dimensions, or the magnetization direction with respect to the magnet geometry, because the magnets are not in contact with each other or at least the surfaces of these magnets do not touch each other Can be obtained.

  The magnets forming the ring are, for example, not in contact with each other or if there is some contact between two angularly continuous magnets in the ring, Corresponds to the corner between the two sides of at least one magnet (it hits the corner or side of another magnet).

  For example, N types of magnets may be provided in the cross section of the generator. Each type of magnet has a predetermined geometric shape in the cross section of the generator, and there is a predetermined relationship between the magnetization direction and the geometric shape, N = 1 or N = 2. By using one type of magnet, or at most two types of magnets each having a unique geometric shape and magnetization direction / geometric shape relationship, great flexibility can be obtained with fewer types of magnets. This is advantageous from a theoretical point of view and is particularly important when producing a product for a specific purpose, which makes it very even when only one or two magnets are to be used. Separators with various sizes and characteristics can be formed, and all magnets can be obtained from cut magnetic bodies using one or two templates.

The present invention described hereinabove can be carried out according to a number of forms. For example, the magnet may have a substantially rectangular shape in cross section.

  Another aspect of the invention relates to a device for separating magnetic particles, the device comprising a non-uniform magnetic field generator having a cross-section with an interior space for receiving an object that has to undergo a magnetic particle separation process. ing. The generator includes a magnet support structure and a plurality of magnets positioned on the support structure. The magnet has a polygonal shape having a plurality of side portions in a cross section of the generator along a plane including the plurality of magnets. The plurality of magnets are arranged at an angle, and in order to generate a magnetic field with P magnetic poles in the internal space, at least one ring made of magnets is formed around the internal space. P is an even number greater than 2.

Hexagon shape, using several types of relationship between the magnetization direction of the magnet and the geometry, it is possible to provide a structure that the scale can be easily changed, it is very useful. This provides advantages (see description above). This structure can be easily scaled by removing, for example, a single ring made of magnets. Such a structure made of magnets that can be easily changed in scale, i.e., a structure having an internal space that can be easily expanded, is such that the magnets are brought into contact with each other with the sides of the magnets placed against the sides of the adjacent magnets. It can be formed by making it into a shape such as a honeycomb.

  Each magnet has a predetermined magnetization direction in the cross section of the generator, and the magnets of the at least one ring have an angle progression of Δy = ((P / 2) +1) × Δθ. Can be positioned to follow. Here, in the cross section of the generator, Δy represents the amount of change in the magnetization direction between one magnet and the next magnet, and Δθ is the change in angular position between one magnet and the next magnet. Represents an amount.

  The at least one ring may comprise more than P magnets (ie, the number of magnets may be greater than the number of magnetic poles in the magnetic field). In this way, a magnetic field having a constant magnetic gradient can be formed in the internal space when P = 4 (if P> 4, the gradient is not constant. For example, when P = 6, the gradient is linear. To zero in the middle, which means that the effectiveness of the separation is low). By using more magnets than the number of poles of the magnetic field, a magnetic field with a large magnetic gradient over the interior space and a substantially constant magnetic field can be obtained. As is well known, as the number of magnets increases, the distortion in the magnetic field contour decreases in the region closest to the magnetic field source (eg, if only four magnets are used, the gradient “distortion nearer to the magnets). However, if a very large number of magnets are used, the gradient is practically perfect, i.e. there is virtually no distortion except in areas very close to the surface of the magnet).

  In the cross section of the generator, N types of magnets are provided. Each type of magnet has a predetermined geometric shape in the cross section of the generator, and there is a predetermined relationship between their magnetization direction and said geometric shape. N is, for example, 1 or 2. By using one type of magnet, or at most two types of magnets with unique geometric shape and magnetization direction / geometric relationship, provide great flexibility and reduce the number of magnet types . This is very good in theory and is particularly important in producing a small series of products. According to the present invention, separators with very different sizes and characteristics can be formed using only one type of magnet or using two types of magnets.

  The generator can be formed such that, in cross-section, the sides of the magnet do not hit the sides of the magnet that are angularly front and back in the ring (but each magnet hits the surface against each other). It may be made up of several magnet pieces). This provides great flexibility in structure, so that various dimensions can be formed using the same magnet or multiple types of magnets without changing the shape or dimensions of the magnet. According to this aspect of the invention, the magnets forming the ring are not in contact with each other, or some or all of the magnets are in contact, but the contact between two angularly continuous magnets in the ring. However, the magnet may be arranged so as to correspond to one corner between two sides of at least one of the magnets and to hit another corner or side of another magnet.

  Any of the aspects of the invention described above may be formed according to various forms including some or all of the following optional features.

  In cross-section, the magnets that make up the magnet ring may have a geometrical direction that follows an angular progression of Δy = ((P / 2) +1) × Δθ. Here, in the cross section of the generator, Δy represents the change in the angular direction of the geometric shape between one magnet and the next magnet, and Δθ is between one magnet and the next magnet. Represents the change in angular position. In other words, the magnets are arranged to change the angular direction of the magnet geometry rather than changing the magnetization direction with respect to the geometry. This is advantageous because the original magnetic material can be cut using a single template, i.e., parts with the same relationship between magnetization and geometry can be produced.

  The number P of magnetic poles may be four. This provides a large constant gradient in the magnetic field across the internal space.

  The magnet forms an equilateral polygonal shape in the cross section of the generator along the plane including the plurality of magnets.

  The magnet may be a parallelepiped.

  In cross section, the magnets may be arranged in a form that includes a plurality of concentric rings made of magnets.

  The structure may include a plurality of magnet rings arranged along the longitudinal axis of the device substantially perpendicular to the cross section.

  One or more magnets may have at least two magnet pieces arranged side by side.

  The support structure may have a plurality of support members (eg, members in the form of an aluminum ring) positioned one after the other along the longitudinal axis of the device. Each support member is provided with a plurality of geometrically shaped holes for receiving the magnets, matching the geometric shape of the magnets.

  The magnet may be made of, for example, NdFeB, SmCo, Ni, or more generally a magnetic anisotropy, eg a magnetocrystalline anisotropy magnet (having this property). Otherwise, there is a risk that the magnet will demagnetize due to the magnetic field generated by the adjacent magnet, which occurs when the material is steel or AlNiCo).

  Another aspect of the invention relates to a method for separating magnetic particles of a subject (eg, a container containing a fluid, eg, a suspension of magnetic particles). According to this aspect of the invention, the method includes placing an object in the interior space of any of the devices described above.

  For the purpose of illustrating and better understanding the features of the present invention according to preferred examples of its actual embodiments, a set of drawings is presented in an illustrative, non-limiting manner as an integral part of the above description.

1 is a schematic perspective view of a support structure for a separator according to an embodiment of the present invention. FIG. 1 is a cross-sectional view of a separator according to an embodiment of the present invention. FIG. 6 is a schematic view of the orientation of magnets and the magnetization directions of these magnets in a cross section of a separator according to another embodiment of the invention. FIG. 6 is a schematic view of the orientation of magnets and the magnetization directions of these magnets in a cross section of a separator according to another embodiment of the invention. 1 is a perspective view of a support structure in an assembled state according to an embodiment of the present invention. FIG. FIG. 6 is a perspective view of a support structure in another assembled state according to an embodiment of the present invention. FIG. 6 is a perspective view of a separator in a completed state according to an embodiment of the present invention.

  FIG. 1 is a schematic view of one preferred embodiment of the present invention, and more particularly, a plurality of, for example, aluminum, schematically shown as rings 21, 22, 23 disposed on a support or base 24. FIG. 1 shows a support structure 2 including a support ring. The free space 1 in the ring is a place for receiving a sample, i.e., an object, on which magnetic particle separation processing is performed.

  As can be seen from the ring 21 (the form of this ring is the same as or substantially the same as the other rings 22 and 23), the support ring has a series of holes or channels 2B where magnets Is housed so as not to move regardless of the attractive or repulsive force exerted between these magnets. The illustrated structure may further be provided with a cover (not shown) that prevents the magnet from moving vertically (ie, parallel to the longitudinal axis of the support structure). FIG. 1 further shows a hole 2A. In these holes 2A are positioned several bars made of brass or stainless steel that are used to keep the ring joined. Basically, these bars together with the aluminum rings 21, 22, 23, the base 24 and a cover (not shown) form a support structure.

  Position the magnet in the channel or hole 2B. Each magnet has two or more magnet pieces that are arranged side by side to form a magnet. The cross section of the magnet coincides with the cross section of the hole or channel 2B, so that the magnet is held in the hole with no play or with a very limited amount of play.

  FIG. 2 shows a support structure 2 of the type shown in FIG. 1 using a plurality of bars 25 made of brass or the like passed through a support ring of the structure, and a plurality of magnets 3 each having a plurality of sides. Schematically shows a method of accommodating the in the hole 2B. In particular, FIG. 2 shows a cross section of the separator, in which the magnet 3 has a polygonal cross section, in detail a rectangular shape or in more detail a square shape. You can see that The magnets are not in contact with each other. In particular, there is no magnet with the sides or surfaces 3a, 3b, 3c, and 3d placed against the surface or side of an adjacent magnet (but without exceeding the scope of the present invention Can be in contact with the corners or sides of adjacent magnets). As can be seen from FIG. 2, the magnets 3 are arranged to form a ring 4 made of magnets, and the fact that the sides of these magnets do not have to touch each other means that one magnet and It means that the magnetization direction can be changed with the next magnet. This is done by adapting the relationship between the magnet and the physical parts that make up the support structure, and the relationship between the magnetization direction (in the cross section of the separator) and the geometry will vary. There is no need to use magnet pieces.

  This concept will be more easily understood by looking at FIG. 3, which shows the distribution of magnets 3 in the cross section of the separator in an embodiment of the invention. As can be seen, the arrows indicating the direction, ie the direction of magnetization 5, have the same relationship for all magnets with respect to the magnet geometry in the plane of the cross section of the separator.

  In detail, the magnetization direction of all magnets is parallel to the two sides of the magnets and perpendicular to the other two sides. This means that, based on the same template, a piece of magnetic material is parallel and perpendicular to the direction in which the material is easily magnetized (ie, the direction that coincides with the so-called “easy axis” of the material). It means that all the magnets can be obtained by cutting into two.

  As shown in FIG. 3 which shows the distribution of the magnets 3 that generate the magnetic fields of four poles in the internal space of the separator, the magnetization direction 5 of the magnets 3 of the magnet ring 4 advances at an angle of Y = 3 × Δθ ( Follow angular progression). Here, ΔY represents the change in the magnetization direction 5 between a certain magnet 3 and the next magnet in the cross section of the generator, and Δθ represents the change in the angular position between the certain magnet 3 and the next magnet. Represent. However, according to the present invention, this is not done by changing the magnetization direction of the magnet with respect to the magnet geometry, but by changing the direction of the magnet geometry with respect to the support structure. Done. Specifically, as can be seen from FIG. 3, the direction of the geometric shape of the magnet 3 forming the magnet ring 4 follows an angular progression of ΔY = 3Δθ. Here, in the cross section of the separator, ΔY represents the amount of change in the angular direction 5 of the geometric shape between a certain magnet 3 and the next magnet, and Δθ represents the difference between the certain magnet and the next magnet. Represents the amount of change in angular position. In other words, since it is not necessary to apply the side part of the magnet to the side part of the adjacent magnet, the angle of the magnetization direction can be advanced in accordance with the progress of the angle in the direction of the physical elements constituting the magnet.

  In the form as shown in FIG. 3, the induction module of the generated magnetic field (B) increases rapidly and from the zero induction at the center of the ring 4 (ie the center of the internal free space 1), the edge (of the magnet ring). Changes to high induction at (near) and the slope is substantially constant, typically several T / m. Due to this constant gradient, the magnetic particles in the sample introduced into the internal space, specifically, for example, in the sample that occupies most of the internal space in the cross section of the separator, move toward the wall of the container. To do. In FIG. 3, the arrows in the “inner space” 1 surrounded by the ring 4 indicate the magnetization gradient and thus the direction of the force exerted on the magnetic particles in the sample, whereby the magnetic particles contain the sample. Move towards the wall of the container. The nearly circular line in FIG. 3 shows the equipotential line, that is, the line formed by the points with the same magnetic field strength value (this also applies to other figures showing this kind of line and arrow). ).

  FIG. 4 shows a magnet distribution according to another embodiment of the present invention. In this embodiment, the magnet 3 is divided and distributed into two rings, and the angular progression of the magnetization direction 5 is the same as that shown in FIG. 3, but in this case, one ring has 22 magnets. Use two rings made of magnets, with the other outer ring containing 30 magnets, use the same kind of magnets as in the configuration of FIG. 3, and have a relatively large magnetic field gradient .

  FIG. 5 illustrates a support structure during assembly according to a preferred embodiment of the present invention. In detail, it can be seen how the three rings 21, 22, 23 made of, for example, aluminum having a height of about 10 mm are fixed to the base plate 24. These rings can be produced, for example, by cutting a 10 mm thick aluminum plate with a laser.

  The rings are secured to each other by a securing system that includes bars 25 made of, for example, brass or non-magnetic stainless steel. The bar 25 is provided with a thread, and the aluminum ring is fixed to a desired height by using, for example, a plastic bolt 26. A method of forming each magnet 3 with two parts 31 and 32 that are combined to form the magnet 3 is schematically shown.

  FIG. 6 shows another assembly process for the separator with the addition of another aluminum ring 20. In this figure, all the magnets 3 are incorporated, and each magnet 3 includes two parts 31 and 32. The structure shown in FIG. 6 has three magnet layers. The magnet may be an NdFeB magnet, for example, or it may be made of any other suitable material depending on the particular property to be obtained.

FIG. 7 shows the separator based on the design shown in FIGS. 5 and 6 in the completed state. The separator is provided with an outer cover 29 and a cover 27, and the cover 27 is fixed to the bar 25 (not shown in FIG. 10) with screws 28.

  In this specification, terms such as “comprises” (such as “comprising”) should not be construed as exclusive. That is, it does not exclude that the described element includes other components, processes, and the like.

  Further, the present invention is not limited to the specific embodiments described above, for example, modifications (e.g., materials, dimensions, components, configurations) by those skilled in the art within the scope of the claims. , Etc.).

Claims (32)

A device for separating magnetic particles,
Comprising a non-uniform magnetic field generator having a cross-section with an internal space (1) for receiving an object to be subjected to a magnetic particle separation process;
The generator has a magnet support structure (2) and a plurality of magnets (3) positioned on the support structure;
The magnet (3) has a polygonal shape with a plurality of sides in a cross section of the generator along a plane containing the plurality of magnets;
The plurality of magnets (3) are arranged at an angle, and in order to generate a magnetic field in the internal space (1) such that the number P of magnetic poles is an even number greater than 2, at least one of the magnets (3) is formed. Forming a ring (4) around the interior space;
Each magnet (3) has a predetermined magnetization direction (5) in the cross section of the generator, and the magnet (3) of the at least one ring (4) has a magnetization direction (5) of the magnet. , Δy = ((P / 2) +1) × Δθ, which is positioned so that, in the cross section of the generator, Δy is the magnetization direction between one magnet and the next ( 5) represents the amount of change, Δθ represents the amount of change in angular position between one magnet and the next magnet, and the at least one ring (4) comprises more than P magnets. ,
N types of magnets are provided in the cross section of the generator, and each of these types of magnets has a predetermined geometric shape in the cross section of the generator, as well as the magnetization direction and the geometric shape. And N = 1 or N = 2. The device of claim 1, wherein
A device characterized in that N = 2. The device of claim 1, wherein
A device characterized in that N = 1. The device according to any one of claims 1 to 3,
The generator is formed such that, in the cross section of the generator, the side portions (3a, 3b, 3c, 3d) of the magnet do not hit the side portions of the magnets in front and rear in the ring. A device characterized by that. The device of claim 4, wherein
Device, characterized in that the magnets (3) forming the ring are not in contact with each other. The device of claim 4, wherein
If there is contact between two angularly continuous magnets (3) of the ring, the contact corresponds to only one corner between two sides of at least one of the two magnets. A device characterized by that. A device for separating magnetic particles,
Comprising a non-uniform magnetic field generator having a cross-section with an internal space (1) for receiving an object to be subjected to a magnetic particle separation process;
The generator has a magnet support structure (2) and a plurality of magnets (3) positioned on the support structure;
The magnet (3) has a polygonal shape with a plurality of sides in a cross section of the generator along a plane containing the plurality of magnets;
The plurality of magnets (3) are arranged at an angle, and in order to generate a magnetic field in the internal space (1) such that the number P of magnetic poles is an even number greater than 2, at least one of the magnets (3) is formed. Forming a ring (4) around the interior space;
Each magnet (3) has a predetermined magnetization direction (5) in the cross section of the generator, and the magnet (3) of the at least one ring (4) has a magnetization direction (5) of the magnet. , Δy = ((P / 2) +1) × Δθ, which is positioned so that, in the cross section of the generator, Δy is the magnetization direction between one magnet and the next ( 5) represents the amount of change, Δθ represents the amount of change in angular position between one magnet and the next magnet, and the at least one ring includes P or more magnets,
The generator is formed such that, in the cross section of the generator, the side portions (3a, 3b, 3c, 3d) of the magnet do not hit the side portions of the magnets in front and rear in the ring. A device characterized by that. The device of claim 7, wherein
Device, characterized in that the magnets (3) forming the ring are not in contact with each other. The device of claim 7, wherein
If there is contact between two angularly continuous magnets (3) of the ring, this contact corresponds to only one corner between the two sides of at least one of the two magnets. A device characterized by that. The device according to any one of claims 7 to 9,
N types of magnets are provided in the cross section of the generator, and each of these types of magnets has a predetermined geometric shape in the cross section of the generator, as well as the magnetization direction and the geometric shape. And N = 1 or N = 2. The device of claim 10, wherein
A device characterized in that N = 2. The device of claim 10, wherein
A device characterized in that N = 1. The device according to any one of claims 1 to 12,
In the cross-section, the magnet has a substantially rectangular polygonal shape. The device according to any one of claims 1 to 13,
In the cross section, the magnet has a substantially hexagonal polygonal shape. A device for separating magnetic particles,
Comprising a non-uniform magnetic field generator having a cross-section with an internal space (1) for receiving an object to be subjected to a magnetic particle separation process;
The generator has a magnet support structure (2) and a plurality of magnets (3) positioned on the support structure;
The magnet (3) has a polygonal shape with a plurality of sides in a cross section of the generator along a plane containing the plurality of magnets;
The plurality of magnets (3) are arranged at an angle, and in order to generate a magnetic field in the internal space (1) such that the number P of magnetic poles is an even number greater than 2, at least one of the magnets (3) is formed. Forming a ring (4) around the interior space,
The polygonal shape is a hexagonal shape. The device of claim 15, wherein
Each magnet (3) has a predetermined magnetization direction (5) in the cross section of the generator, and the magnet (3) of the at least one ring (4) has a magnetization direction (5) of the magnet. , Δy = ((P / 2) +1) × Δθ, which is positioned so that, in the cross section of the generator, Δy is the magnetization direction between one magnet and the next ( 5) represents the amount of change, and Δθ represents the amount of change in the angular position between one magnet and the next magnet. The device according to claim 15 or 16,
Device, characterized in that said at least one ring (4) comprises more than P magnets. A device according to any one of claims 15 to 17,
N types of magnets are provided in the cross section of the generator, and each of these types of magnets has a predetermined geometric shape in the cross section of the generator, as well as the magnetization direction and the geometric shape. And N = 1 or N = 2. The device of claim 18, wherein
A device characterized in that N = 2. The device of claim 18, wherein
A device characterized in that N = 1. A device according to any one of claims 15 to 21,
The generator is formed such that, in the cross section of the generator, the side portions (3a, 3b, 3c, 3d) of the magnet do not hit the side portions of the magnets in front and rear in the ring. A device characterized by that. The device of claim 21, wherein
Device, characterized in that the magnets (3) forming the ring are not in contact with each other. The device of claim 21, wherein
If there is contact between two angularly continuous magnets (3) of the ring, this contact corresponds only to one corner between the two sides of at least one of the two magnets. A device characterized by that. 24. A device according to any one of claims 1 to 23,
In the cross-section, the direction of the geometric shape of the magnet (3) constituting the ring made of magnets follows an angular progression of Δy = ((P / 2) +1) × Δθ, where In the cross section, Δy represents the amount of change in the angular direction of the geometric shape between one magnet and the next magnet, and Δθ represents the amount of change in the angular position between one magnet and the next magnet. A device characterized by representing. 25. A device according to any one of claims 1 to 24,
A device characterized in that the number of magnetic poles P = 4. The device according to any one of claims 1 to 25,
The device, wherein the magnet (3) has an equilateral polygonal shape in the cross section of the generator along the plane containing the plurality of magnets. A device according to any one of claims 1 to 26,
The device, wherein the magnet is a parallelepiped. 28. A device according to any one of claims 1 to 27,
In the cross-section, the magnet is arranged in a form including a plurality of concentric rings made of magnets. A device according to any one of claims 1 to 28,
The device comprising a plurality of rings made of magnets disposed along a longitudinal axis of the device substantially perpendicular to the cross-section. 30. A device according to any one of claims 1 to 29,
At least one magnet of the plurality of magnets has at least two magnet pieces arranged side by side. The device according to any one of claims 1 to 30,
The support structure (2) has a plurality of support members (21, 22, 23) positioned one after the other along the longitudinal axis of the device, each support member receiving the magnet (3) Therefore, the device has a plurality of holes (2B) with a geometric shape that matches the geometric shape of the magnet (3). In a method for separating magnetic particles of interest,
32. A method comprising positioning the object in the internal space of a device according to any one of claims 1-31.