Patent Application
20230025505
The present application is based on, and claims priority from JP Application Serial Number 2021-121305, filed Jul. 26, 2021, the disclosure of which is hereby incorporated by reference herein in its entirety.
The present disclosure relates to a filtration separator for magnetic particles and a filtration separation method for magnetic particles.
JP-A-2013-151713 (Patent Document 1) discloses a washing method for washing a metal powder by separating a foreign substance and a metal powder in a washing tank using a magnet, discharging the foreign substance from the washing tank, and thereafter supplying a washing liquid to the washing tank and dispersing the metal powder in the washing liquid.
However, in the method described in Patent Document 1, when the foreign substance and magnetic particles corresponding to the metal powder are separated, the magnetic particles which were not adsorbed to the magnet are sometimes discharged together with the foreign substance when performing washing. That is, it has been demanded that magnetic particles be efficiently separated in a short time.
A filtration separator for magnetic particles includes a storage tank that stores a liquid in which magnetic particles are dispersed, and that has a bottom portion and a side wall portion, a stirring mechanism having a rotating shaft portion inserted into the storage tank in a direction crossing a face of the bottom portion, and a stirring impeller that is coupled to the rotating shaft portion and that stirs the liquid by rotation of the rotating shaft portion, a magnet mechanism that is provided in at least a part of the side wall portion, and that can switch a magnetic force in the storage tank between an on state and an off state, and that adsorb the magnetic particles in the liquid to the side wall portion when it is in the on state, and a filtration mechanism having a filter provided in the bottom portion of the storage tank, and a discharge port from which the liquid after passing through the filter is discharged.
A filtration separation method for magnetic particles includes storing a liquid in which magnetic particles are dispersed in a storage tank having a bottom portion and a side wall portion, bringing a magnetic force in the storage tank into an on state from at least a part of the side wall portion, adsorbing the magnetic particles to the side wall portion by rotating a rotating shaft portion inserted in a direction crossing a face of the bottom portion and stirring the liquid with a stirring impeller coupled to the rotating shaft portion in a state where the magnetic force is in the on state, filtering the liquid through a filter by discharging the liquid from a discharge port provided in the bottom portion in a state where the magnetic particles are adsorbed to the side wall portion, and placing the magnetic particles adsorbed to the side wall portion on the filter by bringing the magnetic force in the storage tank into an off state.
In the following respective drawings, three axes orthogonal to one another are referred to as X axis, Y axis, and Z axis, and a description will be given. A direction along the X axis is referred to as “X direction”, a direction along the Y axis is referred to as “Y direction”, and a direction along the Z axis is referred to as “Z direction”, and a direction of an arrow is referred to as +direction, and a direction opposite to the +direction is referred to as −direction. The +Z direction is sometimes referred to as “upper” or “upper side”, and the −Z direction is sometimes referred to as “lower” or “lower side”, and viewing from the +Z direction is also referred to as plan view or planar. Further, a face at the +side in the Z direction is referred to as an upper face, and a face at the −side in the Z direction, which is at the opposite side thereto, is referred to as a lower face, and a description will be given.
First, a configuration of a filtration separator 100 for magnetic particles 11 will be described with reference to
As shown in
The stirring mechanism 20 has a storage tank 21, a rotating shaft portion 22, and a stirring impeller 23. The storage tank 21 has a bottom portion 21a, in which a filter 41 is placed, and a side wall portion 21b in a hollow columnar shape coupled to the bottom portion 21a. In the storage tank 21, a liquid 10 in which the magnetic particles 11 are dispersed is stored.
The magnetic particles 11 are, for example, particles to be used in a sol-gel method, and the surface of a core is coated with silicon oxide (SiO2). The liquid 10 is a liquid that is used when forming the magnetic particles 11 by a sol-gel method and that contains the magnetic particles 11 and a reaction liquid 12. Specifically, the liquid 10 contains a so-called material that promotes hydrolysis including tetraethoxysilane.
The rotating shaft portion 22 is inserted in a direction crossing a face of the bottom portion 21a of the storage tank 21. The stirring impeller 23 has a function of stirring the liquid 10 in the storage tank 21, and is constituted by, for example, four blades as shown in
The magnet mechanism 30 has a magnet 31, and the magnet is provided so that it can be put in and out of a storage portion 32 in a pocket-like shape provided in the side wall portion 21b of the storage tank 21. The magnet 31 is formed in, for example, a hollow columnar shape as shown in
By disposing the magnet 31 in the storage portion 32, the position or the height of the magnet 31 in the storage tank 21 can be disposed at a predetermined place. The magnet mechanism 30 can switch the magnetic force in the storage tank 21 between an on state and an off state.
The on state is a state where the magnet 31 is stored in the storage portion 32 and the liquid 10 in the storage tank 21 is affected by a magnetic force. In addition, the on state is a state where the magnet 31 is brought close to the side wall portion 21b of the storage tank 21. When it is in the on state, the magnetic particles 11 in the storage tank 21 move toward the magnet 31.
The off state is a state where the magnet 31 is pulled out of the inside of the storage portion 32 and is a state where the liquid 10 in the storage tank 21 is not affected by a magnetic force. In addition, the off state is a state where the magnet 31 is separated from the side wall portion 21b of the storage tank 21. When it is in the off state, the magnetic particles 11 in the storage tank 21 are in a state of being dispersed in the liquid 10.
As described above, the switching between the on state and the off state can be carried out by moving the magnet 31 in a direction along the side wall portion 21b of the storage tank 21.
The filtration mechanism 40 has a filter 41 disposed in the bottom portion 21a of the storage tank 21, and a discharge port 42 from which a part of the liquid 10 after passing through the filter 41 is discharged. A material to be discharged from the discharge port 42 is the unnecessary reaction liquid 12 of the liquid 10 after performing a coating reaction of the magnetic particles 11 with silicon oxide. The filter 41 can capture the magnetic particles 11 which could not be adsorbed to the magnet 31 by filtering the liquid 10.
The storage portion 32 includes a separation wall 32a that separates the magnet 31 and the magnetic particles 11 adsorbed to the magnet mechanism 30. In other words, the separation wall 32a has a function of a stopper so as to prevent the magnetic particles 11 from going outside the storage tank 21 when the magnet 31 is pulled out of the storage portion 32. The separation wall 32a is provided adjacent to the storage portion 32 at the upper face of the storage tank 21, and is formed so as to protrude toward the center of the storage tank 21 from the storage portion 32.
In an upper part of the storage tank 21, a washing liquid supply portion 50 for supplying a washing liquid 51 into the storage tank 21 is provided. The washing liquid 51 is used for, for example, washing the magnetic particles 11 collected in the storage tank 21.
Next, a filtration separation method for the magnetic particles 11 will be described with reference to
First, as shown in
The coating reaction is performed by stirring the liquid (also referred to as a reaction liquid slurry) in which the magnetic particles 11 and the reaction liquid 12 (for example, a coating material) are mixed with the stirring impeller 23 in this state. That is, by using the magnetic particle 11 as a core and silicon oxide as a shell, a particle in which the surface of the magnetic particle 11 is coated with silicon oxide is completed. In other words, the magnetic particle 11 coated with a gel-like substance is completed.
Subsequently, in Step S12, the magnetic force in the storage tank 21 is brought into an on state. Specifically, as shown in
Subsequently, the liquid 10 is stirred. Specifically, as shown in
In this manner, by continuing to stir the liquid 10 for a predetermined time, as shown in
Subsequently, in Step S14, the liquid 10 is filtered. Specifically, as shown in
That is, the liquid 10 to be discharged from the discharge port 42 is the unnecessary reaction liquid 12 left over when performing the coating reaction in Step S11. The magnetic particles 11 which were not adsorbed to the magnet 31 are captured by the filter 41 disposed in the bottom portion 21a of the storage tank 21. By doing this, the magnetic particles 11 and the reaction liquid 12 are separated. When the liquid 10 is discharged, the magnetic particles 11 are not in a state of being collected (for example, in a cake state) on the filter 41, and therefore, the liquid 10 can be discharged quickly and rapidly.
The size of the magnetic particle 11 is, for example, 1.6 μm in diameter. For example, when the size of the magnetic particle 11 is 1.6 μm, the pore diameter of the filter 41 is 0.5 μm, which is about ⅓ or less of the size of the magnetic particle 11.
Subsequently, in Step S15, the magnetic force is brought into an off state. Specifically, as shown in
Since the liquid 10 is filtered through the filter 41 in a state where the magnetic particles 11 are adsorbed to the magnet 31 and thereafter the magnetic particles 11 are gathered together (formed into a cake) and placed on the filter 41 in this manner, the reaction liquid 12 and the magnetic particles 11 can be reliably separated.
Subsequently, in Step S16, the separated magnetic particles 11 are washed. Specifically, as shown in
Subsequently, in Step S17, the washed magnetic particles are dried. As the drying method, for example, drying is performed by allowing air to flow. According to this method, the magnetic particles 11 are dried after being washed, and therefore, for example, the magnetic particles 11 can move on to the subsequent step soon.
Next, the effect of the present embodiment with respect to Comparative Examples will be described with reference to
A table shown in
Further, in the table shown in
Comparative Example 1 is an example in which the collection by magnetic force was not performed. Comparative Example 2 is an example in which the filtration with the filter 41 was not performed, and is a case where washing was performed without forming a cake.
As a result, in Comparative Example 1, when the collection by magnetic force is not performed, the cake formation time by filtration is long, and the time for separating the magnetic particles 11 is prolonged, and therefore, the result is determined to be bad. In Comparative Example 2, when the filtration with the filter 41 is not performed, the washing efficiency is low and also the loss of the magnetic particles 11 increases, and the result is determined to be bad.
On the other hand, in the present embodiment, the collection by magnetic force is performed with the magnet 31 and the filtration is performed using the filter 41, and therefore, the solid-liquid separation time in which the magnetic particles 11 precipitate is short, the washing efficiency is high, and the magnetic particle loss is small. Therefore, all the results can be determined to be good.
As described above, the filtration separator 100 for the magnetic particles 11 of the present embodiment includes the storage tank 21 that stores the liquid 10 in which the magnetic particles 11 are dispersed, and that has the bottom portion 21a and the side wall portion 21b, the stirring mechanism 20 having the rotating shaft portion 22 inserted into the storage tank 21 in a direction crossing a face of the bottom portion 21a, and the stirring impeller 23 that is coupled to the rotating shaft portion 22 and that stirs the liquid 10 by rotation of the rotating shaft portion 22, the magnet mechanism 30 that is provided in at least a part of the side wall portion 21b, and that can switch a magnetic force in the storage tank 21 between an on state and an off state, and that adsorb the magnetic particles 11 in the liquid 10 to the side wall portion 21b when it is in the on state, and the filtration mechanism 40 having the filter 41 provided in the bottom portion 21a of the storage tank 21, and the discharge port 42 from which the liquid 10 after passing through the filter 41 is discharged.
According to the configuration, the filtration mechanism 40 is disposed in the bottom portion 21a of the storage tank 21, and therefore, when the liquid 10 is discharged through the filter 41 from the storage tank 21 while keeping the magnet mechanism 30 in an on state, the magnetic particles 11 which were not adsorbed to the magnet mechanism 30, in other words, the magnetic particles 11 which are fine and difficult to collect by the magnetic force can be captured by the filter 41. Thereafter, by bringing the magnet mechanism 30 into an off state, the magnetic particles 11 can be gathered together on the filter 41, so that the liquid 10, that is, the reaction liquid 12 and the magnetic particles 11 can be reliably separated. Accordingly, the magnetic particles 11 can be separated efficiently without loss in a short time.
Further, in the filtration separator 100 for the magnetic particles 11 of the present embodiment, it is preferred that the magnet mechanism 30 has the magnet 31, and the on state is a state where the magnet 31 is brought close to the side wall portion 21b, and the off state is a state where the magnet 31 is separated from the side wall portion 21b. According to this configuration, the switching between the on state and the off state is carried out by the position of the magnet 31, and therefore, by confirming the position of the magnet 31, the state of the magnetic force in the storage tank 21 can be easily ascertained. In addition, the switching between the on state and the off state can be carried out by a simple configuration.
Further, in the filtration separator 100 for the magnetic particles 11 of the present embodiment, it is preferred that the magnet mechanism 30 switches between the on state and the off state by moving the magnet 31 in a direction along the side wall portion 21b. According to this configuration, the switching between the on state and the off state is carried out by moving the magnet 31 along the side wall portion 21b, and therefore, the magnetic particles 11 can be adsorbed to the side wall portion 21b by a simple configuration.
Further, in the filtration separator 100 for the magnetic particles 11 of the present embodiment, it is preferred that the side wall portion 21b includes the storage portion 32 that stores the magnet 31 when it is in the on state. According to this configuration, the storage portion 32 is included, and therefore, the height or the position of the magnet 31 can be maintained at a predetermined place. Therefore, the magnetic particles 11 can be adsorbed to the predetermined place.
Further, in the filtration separator 100 for the magnetic particles 11 of the present embodiment, it is preferred that the storage portion 32 includes the separation wall 32a that separates the magnet 31 and the magnetic particles 11 collected by the magnet 31. According to this configuration, the separation wall 32a is included, and therefore, the magnetic particles 11 can be prevented from going outside the storage tank 21 together when the magnet 31 is moved.
Further, in the filtration separator 100 for the magnetic particles 11 of the present embodiment, it is preferred that in an upper part above the filter 41 in the storage tank 21, the washing liquid supply portion 50 that supplies the washing liquid 51 into the storage tank 21 is provided. According to this configuration, the washing liquid supply portion 50 is provided, and therefore, the magnetic particles 11 placed on the filter 41 in a gathered state (also referred to as a cake state) can be washed with a small amount of the washing liquid 51. Therefore, the magnetic particles 11 can be efficiently washed in a short time.
Further, the filtration separation method for the magnetic particles 11 of the present embodiment includes storing the liquid 10 in which the magnetic particles 11 are dispersed in the storage tank 21 having the bottom portion 21a and the side wall portion 21b, bringing a magnetic force in the storage tank 21 into an on state from at least a part of the side wall portion 21b, adsorbing the magnetic particles 11 to the side wall portion 21b by rotating the rotating shaft portion 22 inserted in a direction crossing a face of the bottom portion 21a and stirring the liquid 10 with the stirring impeller 23 coupled to the rotating shaft portion 22 in a state where the magnetic force is in the on state, filtering the liquid 10 through the filter 41 by discharging the liquid 10 from the discharge port 42 provided in the bottom portion 21a in a state where the magnetic particles 11 are adsorbed to the side wall portion 21b, and placing the magnetic particles 11 adsorbed to the side wall portion 21b on the filter 41 by bringing the magnetic force in the storage tank 21 into an off state.
According to this method, the liquid 10 is filtered through the filter 41 in a state where the magnetic particles 11 are adsorbed to the side wall portion 21b, and therefore, the magnetic particles 11 which were not adsorbed to the side wall portion 21b, in other words, the magnetic particles 11 which are fine and difficult to collect by the magnetic force can be captured by the filter 41. Thereafter, by bringing the magnetic force into an off state, the magnetic particles 11 can be gathered together on the filter 41, so that the liquid 10, that is, the reaction liquid 12 and the magnetic particles 11 can be reliably separated. Accordingly, the magnetic particles 11 can be separated efficiently without loss in a short time.
Further, in the filtration separation method for the magnetic particles 11 of the present embodiment, it is preferred to include washing the magnetic particles 11 on the filter 41 by supplying the washing liquid 51 from above the filter 41 after placing the magnetic particles 11 on the filter 41. According to this method, washing is performed after the liquid 10 is filtered, and therefore, washing can be efficiently performed with a small amount of the washing liquid 51.
Further, in the filtration separation method for the magnetic particles 11 of the present embodiment, it is preferred to include drying the washed magnetic particles 11 after washing the magnetic particles 11. According to this method, the magnetic particles 11 are dried after being washed, and therefore, for example, the magnetic particles 11 can move on to the subsequent step soon.
Hereinafter, modifications of the above-mentioned embodiment will be described.
As described above, the magnet 31 is not limited to being a permanent magnet, and for example, an electromagnet may be used. Specifically, the on state and the off state of the magnetic force are operated with an electrical electromagnet.
In this manner, it is preferred that the magnet mechanism 30 of the modification has an electromagnet, and the on state is a state where electricity is applied to the electromagnet, and the off state is a state where electricity is not applied to the electromagnet. According to this configuration, the switching between the on state and the off state can be electrically carried out using an electromagnet, and therefore, it can be dealt with by providing an electrical facility. Further, it is magnetically safe.
Further, after completing the washing of the magnetic particles 11, washing may be performed by adsorbing the magnetic particles 11 again using the magnet 31 and removing the washing liquid 51, and then supplying the washing liquid 51 into the storage tank 21. That is, washing may be repeated multiple times.
Further, when the magnetic particles 11 are washed, it is not limited to dispersing and stirring the magnetic particles 11 in a small amount of the washing liquid 51, and for example, washing may be performed by allowing the washing liquid 51 to pass through from above a cake composed of the magnetic particles 11. According to this, an unnecessary component is concentrated and discharged, and therefore, as compared with a method of diluting the unnecessary component by dispersing the magnetic particles 11 in the washing liquid 51, the magnetic particles 11 can be efficiently washed with a smaller amount of the washing liquid 51.
Further, as the filtration method, a pressurized filtration method or a vacuum filtration method may be adopted according to need. In addition, the washing state of the magnetic particles 11 may be ascertained by monitoring the properties (such as pH) of the filtrate.
Further, the magnet 31 is not limited to one having a circular ring shape with the entire circumference coupled, and for example, may be a magnet in a circular ring shape divided into multiple parts. In addition, the divided magnet may be configured to rotate along the side wall portion 21b of the storage tank 21.
Further, the above-mentioned filtration separator 100 or filtration separation method may be applied to the use of detection of a viral gene to be used in a PCR test or the like. In addition, it is also applicable to the extraction and washing of a nucleic acid or a protein.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2021-121305 | Jul 2021 | JP | national |
