Sample agitating mechanism and analysis device

Abstract

This sample agitating mechanism comprises a sample cell, an agitator that includes a ferromagnetic body and is formed in a rod shape, and that is disposed in the sample cell, and a rod-shaped magnet that is disposed below the sample cell and that rotates with an opposing direction, opposing the sample cell, as an axial direction, wherein: the relative position between the agitator and the magnet is maintained at an agitating position where both ends, in the longitudinal direction, of the agitator are attracted to the center of gravity of the magnet as a result of the agitator receiving a magnetic force from the magnet; and the agitator rotates in conjunction with the magnetic, with the opposing direction as the axial direction.

Description

Sample stirring mechanism and analytical instrument

[0001] The present invention relates to a sample stirring mechanism and an analytical apparatus. This application claims priority based on Japanese Patent Application No. 2025-042604, filed in Japan on March 17, 2025, the contents of which are incorporated herein by reference.

[0002] In analytical instruments used for qualitative and quantitative analysis of biological samples such as blood and urine, analysis is performed by mixing the biological sample with reagents and buffer solutions. To achieve highly accurate analysis, it is necessary to thoroughly mix the biological sample, reagents, and buffer solutions.

[0003] Sample stirring mechanisms for stirring a target substance within a sample cell include the shaking type, which stirs by shaking the sample cell; the gas-blowing type, which stirs by blowing gas into the target substance; and the rotary type, which stirs by rotating a stirring bar within the sample cell.

[0004] In rotary sample stirring mechanisms, a mechanism for stirring a sample using magnets is known. For example, Patent Document 1 describes a sample stirring mechanism in which a magnet is placed as a stirring bar inside a sample cell, a magnet is placed below the sample cell, and the magnet placed below the sample cell is rotated to rotate the magnet placed inside the sample cell, thereby stirring the target substance inside the sample cell.

[0005] Japanese Patent Publication No. 2001-009253

[0006] However, in the sample stirring mechanism described in Patent Document 1, a repulsive force acts between the magnet inside the sample cell and the magnet positioned below the sample cell during rotation, disrupting the rotation of the magnet inside the sample cell and sometimes preventing sufficient stirring of the target substance inside the sample cell.

[0007] The present invention aims to provide a sample stirring mechanism and analytical apparatus that can rotate a stirring bar in a sample cell in a stable state without having a complex configuration.

[0008] To solve the above problems, the present invention proposes the following means: (1) A sample stirring mechanism according to one aspect of the present invention comprises a sample cell, a stirring bar formed in the shape of a rod containing a ferromagnetic material and placed inside the sample cell, and a rod-shaped magnet placed below the sample cell and rotating axially in a direction opposite to the sample cell, wherein the relative position of the stirring bar and the magnet is maintained in a stirring position in which both ends of the longitudinal direction of the stirring bar are attracted to the center of gravity of the magnet as the stirring bar receives magnetic force from the magnet, and the stirring bar rotates axially in the direction opposite to the magnet in conjunction with the magnet.

[0009] (2) One aspect of the present invention is characterized in that, in the sample stirring mechanism of (1), the stirring position is a position in which the center of gravity of the magnet and the center of gravity of the stirring bar coincide when viewed from the opposing direction.

[0010] (3) One aspect of the present invention is a sample stirring mechanism according to (1) or (2), characterized in that the stirring bar is cylindrical and the magnet is cylindrical.

[0011] (4) One aspect of the present invention is characterized in that, in any one of the sample stirring mechanisms of (1) to (3), the longitudinal length of the stirring bar is 1.1 to 2 times the longitudinal length of the magnet.

[0012] (5) One aspect of the present invention is characterized in that, in any one of the sample stirring mechanisms (1) to (4), the radial length of the stirring bar is 1.0 times or less the radial length of the magnet.

[0013] (6) One aspect of the present invention is characterized in that, in any one of the sample stirring mechanisms of (1) to (5), the longitudinal length of the stirring bar is 5.8 mm to 9.8 mm, and the radial length of the stirring bar is 0.5 mm to 2 mm.

[0014] (7) One aspect of the present invention is characterized in that, in any one of the sample stirring mechanisms (1) to (6), the longitudinal length of the magnet is 5 mm to 10 mm, and the radial length of the magnet is 4 mm to 10 mm.

[0015] (8) One aspect of the present invention is characterized in that, in any one of the sample stirring mechanisms of (1) to (7), the upper end of the magnet is formed in a linear shape extending in the longitudinal direction.

[0016] (9) One aspect of the present invention is characterized in that, in any one of the sample stirring mechanisms of (1) to (8), the sample cell has a columnarly formed housing portion.

[0017] (10) One aspect of the present invention is characterized in that, in any one of the sample stirring mechanisms of (1) to (9), the sample cell has a cylindrically formed housing portion.

[0018] (11) One aspect of the present invention is a sample stirring mechanism according to any one of (1) to (10), characterized in that the radial length of the housing is 1.1 to 1.5 times the longitudinal length of the stirring bar.

[0019] (12) An analytical apparatus according to one aspect of the present invention is an analytical apparatus equipped with any one of the sample stirring mechanisms of (1) to (11), comprising a cartridge having the sample cell and an apparatus body having an insertion part into which the cartridge can be inserted, wherein the magnet is provided below the insertion part.

[0020] According to the present invention, it is possible to provide a sample stirring mechanism and an analytical apparatus that can rotate a stirring bar in a sample cell in a stable state without having a complex configuration.

[0021] It is a functional configuration diagram of the sample stirring mechanism according to the present embodiment. It is a side view showing a stirring bar attracted to a magnet. It is a cross-sectional view of the stirring bar and the magnet shown in Fig. 2, taken along line F3-F3. It is a diagram showing the magnitude of the force applied in the X direction to the first end of the stirring bar. It is a diagram showing the magnitude of the force applied in the X direction to both ends of the stirring bar. It is a diagram showing how the stirring bar receives a force from the magnet. It is a diagram showing the magnitude of the force applied in the Y direction from the magnet to the stirring bar. It is a perspective view showing the analyzer according to the present embodiment. It is a plan view showing a cartridge. It is a functional configuration diagram of the cartridge. It is a diagram showing measurement results of Comparative Examples 1 to 3 and Examples 1 to 3. It is a diagram showing the state of measurement of Comparative Examples 1 to 3 and Example 1.

[0022] Hereinafter, a sample stirring mechanism and an analyzer according to an embodiment will be described with reference to the drawings. In the following description, components having the same or similar functions are assigned the same reference numerals. Duplicate descriptions of these components may be omitted as appropriate.

[0023] [Sample Stirring Mechanism 100] A sample stirring mechanism 100 according to the present embodiment will be described with reference to Figs. 1 to 7. First, the overall configuration of the sample stirring mechanism 100 will be described. However, the sample stirring mechanism 100 does not need to include all of the configurations described below, and some configurations may be omitted as appropriate.

[0024] Fig. 1 is a functional configuration diagram of the sample stirring mechanism 100 according to the present embodiment. The sample stirring mechanism 100 is a mechanism capable of stirring a sample. As shown in Fig. 1, the sample stirring mechanism 100 includes a sample cell 1, a stirring bar 2, and a rotating unit 3.

[0025] In the present embodiment, the vertical direction of the sample cell 1 is defined as the vertical direction Z of the sample stirring mechanism 100, the vertically upward direction is defined as upward Z1, and the vertically downward direction is defined as downward Z2.

[0026] The sample cell 1 is a container that accommodates a sample to be stirred. The sample cell 1 has an accommodating portion 11 formed in a columnar shape with the vertical direction Z as the height direction.

[0027] The stirring bar 2 is a component that stirs the sample contained in the sample cell 1. The stirring bar 2 is placed inside the sample cell 1. Specifically, the stirring bar 2 is placed in the housing section 11. The stirring bar 2 is a cylindrical component. The longitudinal direction of the stirring bar 2 is defined as the first longitudinal direction L. The stirring bar 2 is placed so that the first longitudinal direction L is oriented in the radial direction of the housing section 11. The stirring bar 2 is placed so that its center of gravity G1 substantially coincides with the center of the housing section 11. The stirring bar 2 is made of a ferromagnetic material. For example, the stirring bar 2 is made of at least one metal selected from the group consisting of iron, cobalt, or nickel, an alloy or compound containing the metal, and is preferably made of iron, an iron-containing alloy or compound.

[0028] The length V2 of the first longitudinal direction L of the stirring bar 2 is, for example, 5.8 mm to 9.8 mm. The radial length V3 of the stirring bar 2 is, for example, 0.5 mm to 2 mm. More preferably, the radial length V3 of the stirring bar 2 is 1.5 mm to 2 mm.

[0029] The rotating part 3 is a component that rotates the stirring bar 2. The rotating part 3 is positioned below Z2 of the sample cell 1. As shown in Figure 1, the rotating part 3 has a turntable 31 and a magnet 32.

[0030] The rotating base 31 is a component that rotates the magnet 32 ​​with the vertical direction (opposing direction) Z as its axial direction. As shown in Figure 1, the rotating base 31 has a base 31a and a rotating plate 31b that rotates with respect to the base 31a with the vertical direction Z as its axial direction. The rotating plate 31b is rotated by, for example, a pulse motor. When viewed from above Z1, the rotating plate 31b rotates in both clockwise (CW) and counterclockwise (CCW) directions.

[0031] The magnet 32 ​​is a component that moves the stirring bar 2 by magnetic force. The magnet 32 ​​is positioned below Z2 of the sample cell 1. The magnet 32 ​​is positioned so that its center of gravity G2 is approximately coincident with the center of the housing 11. The magnet 32 ​​is fixed to the upper surface of the rotating plate 31b. The magnet 32 ​​is a cylindrical component. The longitudinal direction of the magnet 32 ​​is defined as the second longitudinal direction M. The magnet 32 ​​is polarized into an N pole and an S pole in the second longitudinal direction M. In the magnet 32, of the ends in the second longitudinal direction M, one first end 32n is the N pole, and the other second end 32s is the S pole. Note that the N pole and S pole may be reversed.

[0032] The length V4 of the second longitudinal direction M of the magnet 32 ​​is, for example, 5 mm to 10 mm. The radial length V5 of the magnet 32 ​​is, for example, 4 mm to 10 mm.

[0033] The radial length V1 of the housing section 11 is 1.1 to 1.5 times the length V2 of the first longitudinal direction L of the stirring bar 2.

[0034] The length V2 of the first longitudinal direction L of the stirring bar 2 is 1.1 to 2 times the length V4 of the second longitudinal direction M of the magnet 32. Alternatively, the length V2 of the first longitudinal direction L of the stirring bar 2 may be 0.6 to 2 times the length V4 of the second longitudinal direction M of the magnet 32. The length V2 of the first longitudinal direction L of the stirring bar 2 may also be smaller than the length V4 of the second longitudinal direction M of the magnet 32.

[0035] The radial length V3 of the stirring bar 2 is 1 or less of the radial length V5 of the magnet 32. Preferably, the radial length V3 of the stirring bar 2 is 0.1 to 1 times the radial length V5 of the magnet 32.

[0036] [Operation of the sample stirring mechanism 100] Next, the operation of the sample stirring mechanism 100 will be explained with reference to Figures 2 to 7.

[0037] Since the stirring bar 2 is made of a ferromagnetic material, when placed in a space where a magnetic field is generated, it becomes magnetized and polarized into a north pole and a south pole. Since the stirring bar 2 is placed in the housing 11 of the sample cell 1, it becomes magnetized by the magnetic field formed by the magnet 32 ​​located below Z2 of the sample cell 1. The stirring bar 2 becomes polarized into a north pole and a south pole in the first longitudinal direction L.

[0038] Of the ends of the stirring bar 2 in the first longitudinal direction L, the end closest to the first end 32n of the magnet 32, which is the north pole, becomes the south pole, and the end closest to the second end 32s of the magnet 32, which is the south pole, becomes the north pole. Of the ends of the stirring bar 2 in the first longitudinal direction L, the end that has become the south pole is designated as the first end 2s, and the end that has become the north pole is designated as the second end 2n.

[0039] Figure 2 is a side view showing the agitator 2 attracted to the magnet 32. Figure 3 is a cross-sectional view of the agitator 2 and magnet 32 ​​shown in Figure 2 along the line F3-F3. The first end 2s of the agitator 2, which is the south pole, is attracted to the first end 32n of the magnet 32, which is the north pole. Also, the second end 2n of the agitator 2, which is the north pole, is attracted to the second end 32s of the magnet 32, which is the south pole.

[0040] At this time, the stirring bar 2 is attracted to the magnet 32 ​​in the vertical direction Z, but the lower end of the stirring bar 2 is in contact with the upper surface of the housing 11, so the length in the vertical direction Z between the stirring bar 2 and the magnet 32 ​​is determined by the length in the vertical direction Z between the upper surface of the housing 11 and the magnet 32.

[0041] As shown in Figures 2 and 3, the stirring bar 2, attracted by the magnet 32, stabilizes with its center of gravity G1 coinciding with the center of gravity G2 of the magnet 32, and with its first longitudinal direction L and second longitudinal direction M coinciding.

[0042] Here, we will explain the process by which the stirring bar 2, attracted by the magnet 32, stabilizes when its center of gravity G1 coincides with the center of gravity G2 of the magnet 32, and when its first longitudinal direction L and second longitudinal direction M coincide.

[0043] Fig. 4 is a diagram illustrating the magnitude of the force received in the X direction by the first end 2s of the stirring bar 2. Fig. 5 is a diagram illustrating the magnitude of the force received in the X direction by both ends 2s and 2n of the stirring bar 2. First, the action in the X direction along the first longitudinal direction L will be described. In the X direction, the first end 2s side of the stirring bar 2 is defined as the -X direction, and the second end 2n side of the stirring bar 2 is defined as the +X direction.

[0044] A force F that the first end 2s of the stirring bar 2 is attracted in the X direction by the magnet 32 Ｘ１ is calculated by the following formulas (1) and (2). F Ｘ１ =F ｄ１ cos(atan(d / X １ )) ...(1) F ｄ１ =F ｔ / (√(X １ ２ +d ２ )) ...(2) F ｄ１ is a force by which the first end 2s of the stirring bar 2 is attracted to the first end 32n of the magnet 32. F ｔ is a force by which the stirring bar 2 is attracted to the magnet 32 per unit distance. X １ is the relative position of the first end 2s of the stirring bar 2 with respect to the first end 32n of the magnet 32 in the X direction. d is the length between the stirring bar 2 and the magnet 32 in the vertical direction Z.

[0045] According to formulas (1) and (2), the force F Ｘ１ is a composite function of a trigonometric function and a distance function, as shown in Fig. 4.

[0046] A force F that the second end 2n of the stirring bar 2 is attracted in the X direction by the magnet 32 Ｘ２ is calculated by the following formulas (3) and (4). F Ｘ２ =F ｄ２ cos(atan(d / X ２ )) ...(3) F ｄ２ =F ｔ / (√(X ２ ２ +d ２ )) ...(4) F ｄ２ is a force by which the second end 2n of the stirring bar 2 is attracted to the second end 32s of the magnet 32. X ２This is the relative position of the second end 2n of the stirring bar 2 with respect to the second end 32s of the magnet 32 ​​in the X direction.

[0047] According to equations (3) and (4), the force F Ｘ２ As shown in Figure 5, this is a composite function of trigonometric functions and distance functions.

[0048] As shown in Figure 5, when both ends 2s and 2n of the stirring bar 2 are in region b, the stirring bar 2 stabilizes at a position where the center of gravity G1 of the stirring bar 2 coincides with the center of gravity G2 of the magnet 32 ​​due to the balance of forces. Among the relative positions of the stirring bar 2 with respect to the magnet 32, the position of the stirring bar 2 where the center of gravity G1 of the stirring bar 2 and the center of gravity G2 of the magnet 32 ​​coincide when viewed from the vertical direction (opposing direction) Z is defined as stirring position P1, and the stirring bar 2 located at stirring position P1 is defined as stirring bar 2 (P1). At stirring position P1, both ends 2s and 2n of the stirring bar 2 are attracted to the center of gravity G2 of the magnet 32.

[0049] When the stirring bar 2 is located at the stirring position P1, the first end 2s receives a force F from the magnet 32, as shown in Figure 5. Ｘ１ The force F that the second end 2n receives from the magnet 32 Ｘ２ This is approximately equal to the given value. Therefore, the stirring bar 2 is stable at the stirring position P1.

[0050] When the stirring bar 2 is located in the -X direction from the stirring position P1, the force F exerted on the first end 2s by the magnet 32 ​​is Ｘ１ The force F that the second end 2n receives from the magnet 32 Ｘ２ The resultant force acts in the +X direction. Therefore, the stirring bar 2 receives a force that moves it towards the stirring position P1.

[0051] When the stirring bar 2 is located in the +X direction from the stirring position P1, the force F exerted on the first end 2s by the magnet 32 ​​is Ｘ１ The force F that the second end 2n receives from the magnet 32 Ｘ２ The resultant force acts in the -X direction. Therefore, the stirring bar 2 receives a force that moves it towards the stirring position P1.

[0052] Even if the stirring bar 2 is displaced from the stirring position P1 in either the -X direction or the +X direction, the stirring bar 2 will receive a force that moves it closer to the stirring position P1, so the stirring bar 2 will be returned to the stirring position P1 and maintained at the stirring position P1.

[0053] Figure 6 shows how the stirring bar 2 receives force from the magnet 32. Figure 7 shows the magnitude of the force that the stirring bar 2 receives from the magnet 32 ​​in the Y direction. Next, the action in the Y direction will be explained. The Y direction is defined as the direction perpendicular to the X direction and the vertical Z direction, and the left side when viewed from the +X direction is the -Y direction and the right side is the +Y direction.

[0054] The force F exerted by the magnet 32 ​​to pull the stirring bar 2 in the Y direction Ｙ F is calculated by the following equations (5) and (6). Ｙ = F ｄＹ cos(atan(d / Y １ )) ... (5) F ｄＹ = F ｔ / (√(Y １ ２ +d ２ )) ... (6) F ｄＹ This is the force that attracts the stirring bar 2 to the first end 32n of the magnet 32. １ This is the relative position of the stirring bar 2 with respect to the magnet 32 ​​in the Y direction.

[0055] According to equations (5) and (6), the force F Ｙ As shown in Figure 7, this is a composite function of trigonometric functions and distance functions.

[0056] When the stirring bar 2 is located at the stirring position P1, the force F that the stirring bar 2 receives from the magnet 32 ​​is as shown in Figure 7. Ｙ It does not work. Therefore, the stirring bar 2 is stable at the stirring position P1.

[0057] When the stirring bar 2 is located in the -Y direction from the stirring position P1, the force F exerted on the stirring bar 2 by the magnet 32 ​​is Ｙ This force acts in the +Y direction. Therefore, the stirring bar 2 receives a force that moves it towards the stirring position P1.

[0058] When the stirring bar 2 is located in the +Y direction from the stirring position P1, the force F exerted on the stirring bar 2 by the magnet 32 ​​is Ｙ This force acts in the -Y direction. Therefore, the stirring bar 2 receives a force in the direction that moves it toward the stirring position P1.

[0059] If the stirring bar 2 shifts in the Y direction from the stirring position P1, it will experience a force that moves it closer to the stirring position P1, thus maintaining the stirring bar 2 at the stirring position P1. At the stirring position P1, the center of the stirring bar 2 and the center of the magnet 32 ​​are approximately coincident when viewed from the X direction, so the first longitudinal direction L and the second longitudinal direction M are also approximately coincident.

[0060] Even if the magnet 32 ​​rotates, the stirring bar 2 is maintained at the stirring position P1. Therefore, when the magnet 32 ​​rotates with the vertical direction Z as its axis, the stirring bar 2 is pulled by the rotating magnet 32 ​​and follows, rotating with the vertical direction Z as its axis. Even if the stirring bar 2 deviates from the stirring position P1 during rotation, it receives a force in the direction of approaching the stirring position P1, so it rotates while maintaining the stirring position P1. As a result, the stirring bar 2 can rotate stably and sufficiently stir the sample contained in the storage section 11.

[0061] When the stirring bar 2 is rotating, it may shift slightly from the stirring position P1, for example, due to centrifugal force, but it is pulled back to the stirring position P1 by the magnet 32. Even after returning to the stirring position P1, the stirring bar 2 may shift again due to centrifugal force, etc., but it is pulled back to the stirring position P1 by the magnet 32 ​​again. While rotating, the stirring bar 2 is maintained at the stirring position P1 by repeatedly shifting away from the stirring position P1 and returning to the stirring position P1.

[0062] According to the sample stirring mechanism 100 of this embodiment, the device comprises a sample cell 1, a ferromagnetic stirring bar 2 formed in the shape of a rod and placed inside the sample cell 1, and a rod-shaped magnet 32 ​​placed below Z2 of the sample cell 1 and rotating axially in the opposing direction (up and down direction Z) opposite to the sample cell 1. The relative position of the stirring bar 2 and the magnet 32 ​​is maintained at a stirring position P1 in which both ends 2s and 2n of the first longitudinal direction L of the stirring bar 2 are attracted to the center of gravity G2 of the magnet 32 ​​by the magnetic force the stirring bar 2 receives from the magnet 32. Since the stirring bar 2 rotates axially in the opposing direction (up and down direction Z) in conjunction with the magnet 32, a sample stirring mechanism can be provided that can rotate the stirring bar 2 inside the sample cell 1 in a stable state without having a complex configuration.

[0063] According to the sample stirring mechanism 100 of this embodiment, the stirring bar 2 is cylindrical and the magnet 32 ​​is cylindrical. Therefore, the lower end of the stirring bar 2 is formed in a linear shape along the first longitudinal direction L, and the upper end of the magnet 32 ​​is formed in a linear shape along the second longitudinal direction M. The lower end of the stirring bar 2 is strongly attracted to the upper end of the magnet 32, so the stirring bar 2 receives a force along the second longitudinal direction M, and stabilizes in a state where the first longitudinal direction L and the second longitudinal direction M coincide. As a result, the relative position of the stirring bar 2 with respect to the magnet 32 ​​becomes even more stable.

[0064] According to the sample stirring mechanism 100 of this embodiment, since the stirring bar 2 is formed in a cylindrical shape, even if it rotates with the first longitudinal direction L as the axial direction, its relative position to the magnet 32 ​​does not change, and the force it receives from the magnet 32 ​​does not change. Therefore, it is possible to provide a sample stirring mechanism 100 that can rotate the stirring bar 2 in the sample cell 1 in a stable state.

[0065] According to the sample stirring mechanism 100 of this embodiment, since the housing portion 11 of the sample cell 1 is formed in a cylindrical shape, when the stirring bar 2 rotates, the length from the center of gravity G1 of the stirring bar 2 to the side wall of the housing portion 11 is always constant, so that the sample housed in the housing portion 11 can be stirred uniformly.

[0066] In the sample stirring mechanism 100 according to this embodiment, the magnet 32 ​​rotates with the vertical direction Z as its axial direction, but the configuration of the rotating part 3 is not limited. The magnet 32 ​​may rotate with the opposing direction in which the magnet 32 ​​and the sample cell 1 face each other as its axial direction. For example, the magnet 32 ​​may rotate with a direction inclined from the vertical direction Z as its axial direction.

[0067] In the sample stirring mechanism 100 according to this embodiment, at the stirring position P1, the center of gravity G1 of the stirring bar 2 and the center of gravity G2 of the magnet 32 ​​are approximately coincident when viewed from the vertical direction Z, but the stirring position P1 is not limited. At the stirring position P1, the center of gravity G1 of the stirring bar 2 may be slightly offset from the center of gravity G2 of the magnet 32 ​​due to design errors, etc.

[0068] In the sample stirring mechanism 100 according to this embodiment, the stirring bar 2 is cylindrical and the magnet 32 ​​is cylindrical, but the shapes of the stirring bar 2 and the magnet 32 ​​are not limited. The magnet 32 ​​only needs to be formed in a linear shape with its upper end extending in the second longitudinal direction M. For example, the magnet 32 ​​may be formed in a polygonal shape with its upper end as the vertex when viewed from the second longitudinal direction M.

[0069] In the sample stirring mechanism 100 according to this embodiment, the housing portion 11 of the sample cell 1 is formed in a cylindrical shape, but the shape of the housing portion 11 is not limited. The housing portion 11 only needs to be formed in a rotationally symmetric shape when viewed from the vertical direction Z. For example, the housing portion 11 may be formed in a regular polygon shape when viewed from the vertical direction Z.

[0070] [Analytical Apparatus 200] Next, the analytical apparatus 200 will be described with reference to Figures 8 to 10. However, the analytical apparatus 200 does not need to have all of the configurations described below, and some configurations may be omitted as appropriate.

[0071] Figure 8 is a perspective view showing the analytical apparatus 200 according to this embodiment. The analytical apparatus 200 according to this embodiment is a device capable of measuring a target substance in a biological sample. The analytical apparatus 200 according to this embodiment is a device for analyzing blood as a biological sample. The analytical apparatus 200 is a device equipped with a sample stirring mechanism 100.

[0072] As shown in Figure 8, the analyzer 200 comprises a main unit 201 and a cartridge 202. The analyzer 200 is used with the cartridge 202 inserted into the main unit 201.

[0073] The main body of the device 201 has a cartridge insertion section (insertion section) 201a into which a cartridge can be inserted. Below the cartridge insertion section 201a, Z2, there is a rotating section 3 having a magnet 32. The rotating section 3 is positioned so as to overlap with the cartridge insertion section 201a when viewed from the vertical direction Z.

[0074] Figure 9 is a plan view showing the cartridge 202. Figure 10 is a functional configuration diagram of the cartridge 202. The cartridge 202 is a component that contains a biological sample. The cartridge 202 is used when inserted into the cartridge insertion section 201a.

[0075] As shown in Figures 9 and 10, the cartridge 202 includes a dispensing port 202a, a weighing section 202b, a sample cell 1, a buffer solution storage section 202c, a separation section 202d, and a measurement section 202e.

[0076] The dispensing port 202a is an opening into which the biological sample to be measured can be dropped. The dispensing port 202a is formed at the upper end of the cartridge 202. The dispensing port 202a is in communication with the weighing section 202b.

[0077] The weighing unit 202b is a storage unit in which a biological sample is contained when quantifying a biological sample. The weighing unit 202b is located inside the cartridge 202. The weighing unit 202b is in communication with the sample cell 1.

[0078] The sample cell 1 is located inside the cartridge 202. When the cartridge 202 is inserted into the cartridge insertion section 201a, the sample cell 1 is positioned to overlap with the rotating section 3 when viewed from the vertical Z direction. The center of the housing section 11 of the sample cell 1 is located approximately at the same position as the center of gravity of the magnet 32 ​​when the cartridge 202 is inserted into the cartridge insertion section 201a. The stirring bar 2 is positioned in the housing section 11.

[0079] The buffer solution container 202c is a component that contains the buffer solution used when agitating the biological sample. The buffer solution container 202c is located inside the cartridge 202. The buffer solution container 202c is in communication with the sample cell 1.

[0080] The separation unit 202d is a component that separates specific components from a biological sample stirred in the sample cell 1. For example, the separation unit 202d is a component that separates plasma from blood, which is a biological sample. The separation unit 202d is located inside the cartridge 202. The separation unit 202d is in communication with the sample cell 1. The separation unit 202d is in communication with the measurement unit 202e.

[0081] The measuring unit 202e is a component that measures the object. The measuring unit 202e is located inside the cartridge 202. The measuring unit 202e is divided into multiple test lines, and measures the object stored in each test line.

[0082] A detector (not shown) is provided inside the main body 201 of the device. The detector is located adjacent to the cartridge insertion section 201a. When the cartridge 202 is inserted into the cartridge insertion section 201a, the detector is located adjacent to the measurement section 202e. In this embodiment, a detector capable of analyzing blood by fluorescence is provided.

[0083] [Operation of the Analytical Device 200] Next, the operation of the analytical device 200 will be explained.

[0084] First, with the cartridge 202 not yet inserted into the cartridge insertion section 201a, blood, which is a biological sample, is dropped into the dispensing port 202a. At this time, reagents may be dropped simultaneously with the blood. After dropping the blood into the dispensing port 202a, the cartridge 202 is inserted into the cartridge insertion section 201a.

[0085] When cartridge 202 is inserted into cartridge insertion section 201a, sample cell 1 is positioned above the rotating section 3 at Z1. At this time, regardless of the orientation of the stirring bar 2 in the housing section 11, the stirring bar 2 moves to the stirring position P1. The stirring bar 2 is polarized by the magnetic field of magnet 32, and both ends 2s and 2n are attracted to both ends 32n and 32s of magnet 32, causing it to move to the stirring position P1.

[0086] The blood poured into the dispensing port 202a is moved to the weighing unit 202b, where it is quantified. The blood quantified in the weighing unit 202b is then moved to the sample cell 1 and stirred by the sample stirring mechanism 100.

[0087] The blood contained in the sample cell 1 is stirred by the stirring bar 2. As the rotating part 3 rotates with the vertical direction Z as its axis, the stirring bar 2 also rotates with the vertical direction Z as its axis, and the blood is stirred. At this time, buffer solution is poured in from the buffer solution container 202c at a predetermined timing.

[0088] The blood, agitated by the sample agitation mechanism 100, moves to the separation unit 202d, where the plasma is separated. The plasma separated by the separation unit 202d moves to the measurement unit 202e.

[0089] The plasma contained in the measurement unit 202e is stored in multiple test lines. The plasma stored in the test lines of the measurement unit 202e is irradiated with fluorescence by a detector provided in the main body of the device 201 and measured.

[0090] The cartridge 202 used for measurement is discarded, for example. The cartridge 202 is disposable, for example, to prevent mixing of the samples being measured. A new cartridge 202 is used when measuring a different sample.

[0091] According to the analytical apparatus 200 of this embodiment, since it is equipped with a sample stirring mechanism 100, it is possible to provide an analytical apparatus that can rotate the stirring bar 2 in the sample cell 1 in a stable state without having a complex configuration. Therefore, the sample to be measured can be sufficiently stirred and analyzed accurately.

[0092] According to the analytical apparatus 200 of this embodiment, since it is equipped with a sample stirring mechanism 100, the stirring bar 2 can be positioned at the stirring position P1 simply by inserting the cartridge 202 into the cartridge insertion section 201a. Therefore, the analytical apparatus 200 is an easy-to-use device without a complex configuration.

[0093] The analytical apparatus 200 according to this embodiment is capable of measuring blood as the sample to be measured, but the apparatus equipped with the sample stirring mechanism 100 is not limited. The sample stirring mechanism 100 may be provided in an apparatus that measures biological samples other than blood, such as mucus or urine. It is not limited to stirring biological samples, but may also be used when stirring water collected from ponds or rivers, or chemical samples.

[0094] Although embodiments of the present invention have been described in detail above with reference to the drawings, the specific configuration is not limited to these embodiments, and design modifications and the like are also included within the scope of the gist of the present invention. Furthermore, the components shown in the above embodiments and modifications can be combined as appropriate.

[0095] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples.

[0096] The equilibrium between the stirring bar 2 and the magnet 32 ​​was measured by changing the shapes of the stirring bar 2 and the magnet 32. SUJ2 (steel) was used for the stirring bar 2. A neodymium magnet was used for the magnet 32. The equilibrium state was defined as the state where the center of gravity G1 of the stirring bar 2 and the center of gravity G2 of the magnet 32 ​​approximately coincided, and the stirring bar 2 was in the stirring position P1.

[0097] Figure 11 shows the measurement results for Comparative Examples 1 to 3 and Examples 1 to 3. Figure 12 shows the measurement process for Comparative Examples 1 to 3 and Example 1.

[0098] As Comparative Example 1, the equilibrium of a stirring bar with a longitudinal length V2 of 5.8 mm and a radial length V3 of 1.5 mm and a cylindrical magnet with a longitudinal length V4 of 15 mm and a radial length V5 of 6 mm was measured. In Comparative Example 1, the longitudinal length V2 of the stirring bar was less than two-fifths of the longitudinal length V4 of the magnet. In Comparative Example 1, the center of gravity G1 of the stirring bar and the center of gravity G2 of the magnet did not coincide, and the stirring bar and magnet were not in equilibrium. In other words, it was found that when the longitudinal length V2 of the stirring bar is less than two-fifths of the longitudinal length V4 of the magnet, the stirring bar and magnet are not in equilibrium.

[0099] As Comparative Example 2, the equilibrium of a stirring bar with a longitudinal length V2 of 5.8 mm and a radial length V3 of 1.5 mm and a cylindrical magnet with a longitudinal length V4 of 25 mm and a radial length V5 of 6 mm was measured. In Comparative Example 2, the longitudinal length V2 of the stirring bar was less than one-quarter of the longitudinal length V4 of the magnet. In Comparative Example 2, the center of gravity G1 of the stirring bar and the center of gravity G2 of the magnet did not coincide, and the stirring bar and magnet were not in equilibrium. In other words, it was found that when the longitudinal length V2 of the stirring bar is less than one-quarter of the longitudinal length V4 of the magnet, the stirring bar and magnet are not in equilibrium.

[0100] As Comparative Example 3, the equilibrium of a stirring bar with a longitudinal length V2 of 9.8 mm and a radial length V3 of 1.5 mm and a cylindrical magnet with a longitudinal length V4 of 2 mm and a radial length V5 of 4 mm was measured. In Comparative Example 3, the longitudinal length V2 of the stirring bar was 4.9 times or more the longitudinal length V4 of the magnet. In Comparative Example 3, the center of gravity G1 of the stirring bar and the center of gravity G2 of the magnet did not coincide, and the stirring bar and magnet were not in equilibrium. In other words, it was found that when the longitudinal length V2 of the stirring bar is 4.9 times or more the longitudinal length V4 of the magnet, the stirring bar and magnet are not in equilibrium.

[0101] In Example 1, the equilibrium between a stirring bar 2 with a longitudinal length V2 of 9.8 mm and a radial length V3 of 1.5 mm and a cylindrical magnet 32 ​​with a longitudinal length V4 of 5 mm and a radial length V5 of 6 mm was measured. In Example 1, the longitudinal length V2 of the stirring bar 2 was approximately 1.96 times the longitudinal length V4 of the magnet 32. In Example 1, the center of gravity G1 of the stirring bar 2 and the center of gravity G2 of the magnet 32 ​​were approximately the same. That is, it was found that when the longitudinal length V2 of the stirring bar 2 is approximately 1.96 times the longitudinal length V4 of the magnet 32, the stirring bar 2 and the magnet 32 ​​are in equilibrium.

[0102] Furthermore, in Example 1, the radial length V3 of the stirring bar 2 was approximately one-quarter of the radial length V5 of the magnet 32. In other words, it was found that when the radial length V3 of the stirring bar 2 is approximately one-quarter of the radial length V5 of the magnet 32, the stirring bar 2 and the magnet 32 ​​are in a state of equilibrium.

[0103] In Example 2, the equilibrium between a stirring bar 2 with a longitudinal length V2 of 5.8 mm and a radial length V3 of 1.5 mm and a cylindrical magnet 32 ​​with a longitudinal length V4 of 5 mm and a radial length V5 of 6 mm was measured. In Example 2, the longitudinal length V2 of the stirring bar 2 was approximately 1.16 times the longitudinal length V4 of the magnet 32. In Example 2, the center of gravity G1 of the stirring bar 2 and the center of gravity G2 of the magnet 32 ​​were approximately the same. That is, it was found that when the longitudinal length V2 of the stirring bar 2 is approximately 1.16 times the longitudinal length V4 of the magnet 32, the stirring bar 2 and the magnet 32 ​​are in equilibrium.

[0104] In Example 3, the equilibrium between a stirring bar 2 with a longitudinal length V2 of 9.8 mm and a radial length V3 of 2 mm and a cylindrical magnet 32 ​​with a longitudinal length V4 of 5 mm and a radial length V5 of 6 mm was measured. In Example 3, the radial length V3 of the stirring bar 2 was approximately one-third of the radial length V5 of the magnet 32. In Example 3, the center of gravity G1 of the stirring bar 2 and the center of gravity G2 of the magnet 32 ​​were approximately the same. That is, it was found that when the radial length V3 of the stirring bar 2 is approximately one-third of the radial length V5 of the magnet 32, the stirring bar 2 and the magnet 32 ​​are in equilibrium.

[0105] As described above, it was found that when the longitudinal length V2 of the stirring bar 2 is 1.1 to 2 times the longitudinal length V4 of the magnet 32, the stirring bar 2 and the magnet 32 ​​are in equilibrium. Furthermore, it was found that when the radial length V3 of the stirring bar 2 is 1.0 times or less the radial length V5 of the magnet 32, the stirring bar 2 and the magnet 32 ​​are in equilibrium.

[0106] 100 Sample stirring mechanism 1 Sample cell 11 Storage section 2 Stirring bar 2s First end 2n Second end G1 Center of gravity 3 Rotating section 31 Rotating base 31a Base 31b Rotating plate 32 Magnet 32n First end 32s Second end G2 Center of gravity 200 Analytical device 201 Main body of the device 201a Cartridge insertion section (insertion section) 202 Cartridge 202a Dispensing port 202b Weighing section 202c Buffer storage section 202d Separation section 202e Measurement section P1 Stirring position Z Up / down direction (opposing direction) Z1 Up Z2 Down L First longitudinal direction M Second longitudinal direction V1 Radial length of storage section 11 V2 Longitudinal length of stirring bar 2 V3 Radial length of stirring bar 2 V4 Length of magnet 32 ​​in the longitudinal direction V5 Length of magnet 32 ​​in the radial direction

Claims

1. A sample stirring mechanism comprising: a sample cell; a ferromagnetic stirring bar formed in the shape of a rod and placed inside the sample cell; and a rod-shaped magnet placed below the sample cell and rotating axially in a direction opposite to the sample cell, wherein the relative position of the stirring bar and the magnet is maintained in a stirring position where both ends of the stirring bar in the longitudinal direction are attracted to the center of gravity of the magnet as the stirring bar receives magnetic force from the magnet, and the stirring bar rotates axially in the direction opposite to the magnet as it is pulled by the rotating magnet.

2. The sample stirring mechanism according to claim 1, wherein the stirring position is the position where the center of gravity of the magnet and the center of gravity of the stirring bar coincide when viewed from the opposing direction.

3. The sample stirring mechanism according to claim 1 or claim 2, wherein the stirring bar is cylindrical and the magnet is cylindrical.

4. The sample stirring mechanism according to claim 1 or claim 2, wherein the longitudinal length of the stirring bar is 1.1 to 2 times the longitudinal length of the magnet.

5. The sample stirring mechanism according to claim 1 or claim 2, wherein the radial length of the stirring bar is 1.0 times or less the radial length of the magnet.

6. The sample stirring mechanism according to claim 1 or claim 2, wherein the longitudinal length of the stirring bar is 5.8 mm to 9.8 mm, and the radial length of the stirring bar is 0.5 mm to 2 mm.

7. The sample stirring mechanism according to claim 1 or claim 2, wherein the length of the magnet in the longitudinal direction is 5 mm to 10 mm, and the length of the magnet in the radial direction is 4 mm to 10 mm.

8. The sample stirring mechanism according to claim 1 or claim 2, wherein the upper end of the magnet is formed in a linear shape extending in the longitudinal direction.

9. The sample stirring mechanism according to claim 1 or claim 2, wherein the sample cell has a columnarly formed housing portion.

10. The sample stirring mechanism according to claim 9, wherein the sample cell has a cylindrically formed housing portion.

11. The sample stirring mechanism according to claim 9, wherein the radial length of the housing is 1.1 to 1.5 times the longitudinal length of the stirring bar.

12. An analytical apparatus comprising a sample stirring mechanism according to claim 1 or claim 2, the apparatus comprising: a cartridge having the sample cell; and a main body having an insertion section into which the cartridge can be inserted, wherein the magnet is provided below the insertion section.

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