Sample freezing device

Abstract

The sample freezing device includes a first support, a retraction mechanism, a second support, a moving mechanism, and a control unit. The first support supports a removal section for removing excess sample solution from an infiltration section containing the sample solution. The retraction mechanism retracts the first support from the removal section at a removal position where the sample solution can be removed from the infiltration section. The second support supports the infiltration section. The moving mechanism moves the second support so that the infiltration section enters a freezing space for freezing the sample solution. The control unit controls the retraction mechanism and the moving mechanism. The control unit controls the retraction of the first support by the retraction mechanism and the movement of the second support by the moving mechanism, such that the time from the retraction of the first support from the removal position until the infiltration section enters the freezing space is less than one second.

Description

Technical Field

[0001] This invention relates to a sample freezing device.

[0002] This application claims priority based on Japanese Patent Application No. 2023-191579, filed in Japan on November 9, 2023, the contents of which are incorporated herein by reference. Background Technology

[0003] Previously, techniques were known to fix the state of a sample, such as a protein, in a desired state by freezing it in a solution. According to such methods, it is easy to observe the sample in the desired state.

[0004] The freezing of the sample is performed, for example, by the apparatus described in Non-Patent Document 1. In this apparatus, firstly, the operator allows the sample solution to permeate the carrier screen. Next, filter paper is brought into contact with the carrier screen via an arm provided by the apparatus to remove excess sample solution. Finally, the arm supporting the filter paper retracts from the carrier screen, and the apparatus lowers the carrier screen into the freezing liquid. Thus, the sample and the solution freeze together.

[0005] Existing technical documents Non-patent literature Non-Patent Document 1: Thermo Fisher Scientific Inc., "Preparation of Low-Temperature EM Samples Using the Vitrobot System", [online], Thermo Fisher Scientific Inc., [Searched November 8, 2006], Internet <URL:https: / / www.thermofisher.com / jp / ja / home / electronn-microscopy / productsample-preparation-equipment-em / vitrobot-system.html> Summary of the Invention The problem that the invention aims to solve According to the experimental results of the inventors of this application, it is sometimes difficult to freeze the sample in the desired state in the device described in Non-Patent Document 1.

[0006] The present invention was made with this in mind, and its purpose is to provide a sample freezing device that can easily freeze a sample in a desired state.

[0007] Methods for solving problems To address the aforementioned issues, the sample freezing apparatus according to Embodiment 1 of the present invention comprises: a first support portion supporting a removal portion for removing excess sample solution from an infiltration portion into which sample solution has infiltrated; a retraction mechanism for retracting the first support portion from a removal position where the removal portion can remove the sample solution from the infiltration portion; a second support portion supporting the infiltration portion; a movement mechanism for moving the second support portion so that the infiltration portion enters a freezing space for freezing the sample solution; and a control portion controlling the retraction mechanism and the movement mechanism, wherein the control portion controls the retraction of the first support portion by the retraction mechanism and the movement of the second support portion by the movement mechanism such that the time from the retraction of the first support portion from the removal position until the infiltration portion enters the freezing space is less than 1 second.

[0008] In addition, according to the sample freezing device of the present invention, in embodiment 2, the retraction mechanism has: a first attracting body that moves in conjunction with the first support; and a first magnetic attracting part that is driven by an electric current to magnetically attract the first attracting body, wherein the control part controls the current flowing in the first magnetic attracting part.

[0009] In addition, according to the sample freezing device of embodiment 1 or embodiment 2, embodiment 3 of the present invention has the following moving mechanism: a second attracting body that engages with the second support portion to restrict the movement of the second support portion; and a second magnetic attracting portion that is driven by an electric current to magnetically attract the second attracting body in order to release the engagement between the second attracting body and the second support portion, wherein the control portion controls the current flowing in the second magnetic attracting portion.

[0010] Furthermore, in the sample freezing device according to any one of embodiments 1 to 3 of the present invention, the moving mechanism has a force-applying part for promoting the movement of the second support.

[0011] Furthermore, in the sample freezing apparatus of any one of embodiments 1 to 4 according to embodiment 5 of the present invention, the removal portion is provided on a single side when viewed from the penetration portion.

[0012] Furthermore, the sample freezing apparatus according to any one of embodiments 1 to 5 of the present invention, in embodiment 6, further includes an optical section that changes the direction of travel of the light from the light source in such a way that light irradiated from the light source irradiates the penetration section.

[0013] Furthermore, in the sample freezing apparatus of embodiment 7 of the present invention, when the penetrating portion is moved toward the freezing space by the moving mechanism, at least a portion of the optical portion moves following the penetrating portion.

[0014] Invention Effects According to the above-described manner of the present invention, a sample freezing apparatus that can easily freeze a sample in a desired state can be provided. Attached Figure Description

[0015] Figure 1 This is a perspective view of the sample freezing apparatus according to an embodiment of the present invention.

[0016] Figure 2A This is a diagram illustrating an example of a carrier mesh into which the sample solution permeates.

[0017] Figure 2B yes Figure 2A An enlarged view of region B shown.

[0018] Figure 2C yes Figure 2B An enlarged view of region C shown.

[0019] Figure 3 This is an exploded view showing the periphery of the base according to an embodiment of the present invention.

[0020] Figure 4 It is along Figure 1 The cross-sectional view shown along line IV-IV.

[0021] Figure 5 This is an exploded view showing the periphery of the second support portion according to an embodiment of the present invention.

[0022] Figure 6A This diagram illustrates the engagement of the limiting mechanism and the second support portion according to an embodiment of the present invention.

[0023] Figure 6B It means succession Figure 6A The diagram shows the state afterward.

[0024] Figure 7 This is a diagram showing the periphery of the first support portion according to an embodiment of the present invention.

[0025] Figure 8A This diagram shows the state in which the first support portion according to an embodiment of the present invention is in the removed position.

[0026] Figure 8B It means succession Figure 8A The diagram shows the state afterward.

[0027] Figure 8C It means succession Figure 8A The diagram shows the other states afterward.

[0028] Figure 9A This is a schematic diagram of the sample freezing apparatus according to an embodiment of the present invention, viewed from the front.

[0029] Figure 9B It means succession Figure 9A The diagram shows the state afterward.

[0030] Figure 9C It means succession Figure 9B The diagram shows the state afterward.

[0031] Figure 10 It is an image obtained by taking a sample frozen using the sample freezing device described in Non-Patent Document 1.

[0032] Figure 11 It is an image obtained by taking a sample frozen by the sample freezing device according to the embodiments of the present invention.

[0033] Figure 12A It means through based on Figure 11 The image shown is a diagram of the three-dimensional model of the sample obtained by analyzing the three-dimensional structure of the image.

[0034] Figure 12B It means to go around Figure 12A The diagram shows a three-dimensional model of the specimen with the rotation axis AX1 rotated by 90°.

[0035] Figure 12C It means to go around Figure 12A The diagram shows a three-dimensional model of the specimen with the rotation axis AX2 rotated by 45°. Detailed Implementation

[0036] Hereinafter, the sample freezing apparatus according to the embodiments of the present invention will be described with reference to the accompanying drawings.

[0037] <Summary> like Figure 1 As shown, the sample freezing apparatus 1 according to this embodiment includes a first support 10, a second support 20, a bracket 30, a guide 40, a retraction mechanism 51, a restraint mechanism 52, an optical part 60, and a control part 70. The sample freezing apparatus 1 according to this embodiment, along with the tweezers assembly 100, the carrier mesh 110 impregnated with the sample solution, the filter paper 120, the freezing container 130, and the light source 140 (see reference...) Figures 9A-9C They are used together. The carrier mesh 110 is supported on the second support 20 via the tweezers assembly 100, and the filter paper 120 is supported on the first support 10 (details are described later).

[0038] Figure 2A This is a diagram illustrating an example of the shape of the carrier net 110. (For example...) Figure 2A As shown, the carrier mesh 110 has a plate portion 111 with a plurality of holes 111a formed therein. The plate portion 111 is, for example, a thin copper plate. The shape of the plate portion 111 is, for example, a circle with a diameter of about a few millimeters. The shape of the holes 111a is, for example, a square with a side length of about tens of micrometers.

[0039] like Figure 2B As shown, a film portion 112 is provided in each hole 111a of the plate portion 111. The film portion 112 is, for example, a carbon film with a thickness of about tens of nm. A plurality of fine holes 112a are formed in the film portion 112. The shape of the fine holes 112a is, for example, a circle with a diameter of about several μm. Figure 2C As shown, a sample solution 114 containing dissolved sample 113 permeates into the pores 112a of the membrane portion 112. The mesh 110 holds the sample solution 114 within the pores 112a by surface tension. The sample 113 may be, for example, a protein. The mesh 110 used for permeating the sample solution is also referred to as the permeation portion.

[0040] Filter paper 120 (reference) Figure 1 The filter paper 120 functions as a removal section to remove excess sample solution from the screen 110.

[0041] The freezing container 130 has a freezing space S for freezing the sample solution. The freezing space S is filled, for example, with a freezing liquid capable of freezing the sample solution. Examples of freezing liquids include liquid ethane, liquid propane, or mixtures thereof. The freezing container 130 is placed, for example, on a work surface such as a table.

[0042] In this embodiment, the freezing container 130 has an opening 130a and a recess 131 formed on its upper surface. The opening 130a communicates with the freezing space S. The recess 131 has an annular shape when viewed from above. The recess 131 surrounds the opening 130a when viewed from above. Liquid ethane may also be filled into the recess 131.

[0043] The sample freezing apparatus 1 of this embodiment removes excess sample solution from the carrier mesh 110 using filter paper 120, and then allows the carrier mesh 110 to enter the freezing space S through the opening 130a. Thus, the sample freezing apparatus 1 freezes the sample solution. Alternatively, the sample solution can be allowed to seep into the carrier mesh 110 after the second support 20 supports it. Or, the second support 20 can be used to support the carrier mesh 110 after the sample solution has seeped into it.

[0044] The following description uses an XYZ orthogonal coordinate system to illustrate the positional relationships of the structure of the sample freezing device 1. In this specification, the X-axis direction is sometimes referred to as the left-right direction (X), the Y-axis direction as the front-back direction (Y), and the Z-axis direction as the up-down direction (Z). The view from the up-down direction (Z) is called a top view. The direction of +X is called the right, and the direction of -X is called the left. The direction of +Y is called the rear (inside), and the direction of -Y is called the front (near the front). The direction of +Z is called the top, and the direction of -Z is called the bottom. In the following description, the case where the up-down direction (Z) coincides with the direction of gravity (gravity direction) will be explained. However, the up-down direction (Z) may not coincide with the direction of gravity. In other words, the up-down direction (Z) may also be tilted relative to the direction of gravity.

[0045] <Standard 30> like Figure 1 as well as Figure 3 As shown, the support 30 according to this embodiment has a bottom 31, a column 32, and a beam 33. The bottom 31 is placed on a work surface such as a table. The bottom 31, the column 32, and the beam 33 are fixed to each other.

[0046] like Figure 1 As shown, the bottom 31 of this embodiment has a U-shaped projection towards the rear (inner side) when viewed from above. The freezing container 130 is disposed, for example, on the inner side of the U-shaped bottom 31. The column portion 32 extends upward from the inner portion of the bottom 31. The beam portion 33 protrudes forward (near the front side) from an appropriate position in the vertical Z direction of the column portion 32. Figure 3 As shown, at least one (two in the illustrated example) threaded hole H1b is formed on the upper surface of the beam 33, which is spaced apart in the front-rear direction Y.

[0047] <Guide Section 40> The guide section 40 guides the movement of the second support section 20 (details are described below). Figure 3 as well as Figure 4 As shown, the guide portion 40 in this embodiment includes a base 41, a pair of guide rods 42A and 42B (first guide rod 42A and second guide rod 42B), a handle 43, a spring bushing 44, a force-applying portion 45 (first helical spring 45A and second helical spring 45B), an adjusting screw 46, a pair of linear bearings 47A and 47B (first linear bearing 47A and second linear bearing 47B), and a mirror fixing portion 48 (see reference). Figure 1 ).

[0048] like Figure 1 as well as Figure 4As shown, a pair of guide rods 42A and 42B extend in the vertical direction Z. The second support 20 is fixed to the pair of guide rods 42A and 42B (details are described later).

[0049] like Figure 4 As shown, each guide rod 42A, 42B passes through the base 41, the spring bushing 44, and the force-applying part 45 (first helical spring 45A and second helical spring 45B) in the vertical direction Z. Each guide rod 42A, 42B is configured to be movable relative to the base 41, the spring bushing 44, and the force-applying part 45 in the vertical direction Z (details are described later).

[0050] The base 41, spring bushing 44, and force-applying part 45 are arranged sequentially from top to bottom with the guide rods 42A and 42B inserted. The base 41, spring bushing 44, and force-applying part 45 are located above the second support part 20 fixed to the guide rods 42A and 42B.

[0051] like Figure 1 as well as Figure 4 As shown, the handle 43 is fixed to a pair of guide rods 42A and 42B by connecting the upper end of the first guide rod 42A to the upper end of the second guide rod 42B. In the illustrated example, the second guide rod 42B is longer than the first guide rod 42A. Therefore, the lower end of the second guide rod 42B is located below the lower end of the first guide rod 42A.

[0052] like Figure 3 As shown, the base 41 in this embodiment has a main portion 41a extending in the left-right direction X and a fixing portion 41b extending in the front-back direction Y.

[0053] The fixing part 41b protrudes rearward from the left end of the main part 41a. At least one threaded hole H1a (two in the illustrated example) is formed in the fixing part 41b, which are arranged at intervals in the front-rear direction Y.

[0054] The threaded hole H1a passes through the fixing part 41b in the vertical direction Z. The screw SC1 is screwed into the threaded hole H1b through the threaded hole H1a, thereby fixing the fixing part 41b to the beam part 33. By fixing the fixing part 41b to the beam part 33, the base 41 is fixed to the bracket 30.

[0055] like Figure 3 as well as Figure 4 As shown, a pair of guide holes 41cA and 41cB (first guide hole 41cA and second guide hole 41cB), an adjustment hole 41d, and a mirror hole 41e are formed in the main part 41a.

[0056] A pair of guide holes 41cA and 41cB are located at the two ends of the main part 41a in the left-right direction X. That is, the first guide hole 41cA is located at the right end of the main part 41a, and the second guide hole 41cB is located at the left end of the main part 41a.

[0057] like Figure 4 As shown, a pair of guide holes 41cA and 41cB penetrate the main part 41a in the vertical direction Z. A pair of guide rods 42A and 42B are inserted into the pair of guide holes 41cA and 41cB, respectively. That is, a first guide rod 42A is inserted into the first guide hole 41cA, and a second guide rod 42B is inserted into the second guide hole 41cB.

[0058] In this embodiment, each guide hole 41cA, 41cB has a small-diameter portion 41c1 and a large-diameter portion 41c2. The small-diameter portion 41c1 opens on the lower surface of the main portion 41a. The large-diameter portion 41c2 opens on the upper surface of the main portion 41a. The small-diameter portion 41c1 and the large-diameter portion 41c2 are interconnected in the vertical direction Z.

[0059] The diameter of the small-diameter portion 41c1 is larger than the diameter of the guide rods 42A and 42B. As a result, the guide rods 42A and 42B are configured to be able to move relative to the base 41 in the vertical direction Z.

[0060] The diameter of the large-diameter portion 41c2 is larger than the diameter of the small-diameter portion 41c1. Therefore, when the guide rods 42A and 42B are inserted into the guide holes 41cA and 41cB, a gap 41g is generated between the inner circumferential surface of the large-diameter portion 41c2 and the outer circumferential surface of the guide rods 42A and 42B.

[0061] The aforementioned pair of linear bearings 47A and 47B are disposed in the gap 41g. Specifically, the first linear bearing 47A is disposed in the gap 41g between the outer peripheral surface of the first guide rod 42A and the inner peripheral surface of the large-diameter portion 41c2 of the first guide hole 41cA. The second linear bearing 47B is disposed in the gap 41g between the outer peripheral surface of the second guide rod 42B and the inner peripheral surface of the large-diameter portion 41c2 of the second guide hole 41cB.

[0062] A pair of linear bearings 47A and 47B guide the movement of a pair of guide rods 42A and 42B in the vertical direction Z, respectively. Specifically, the first linear bearing 47A guides the movement of the first guide rod 42A in the vertical direction Z, and the second linear bearing 47B guides the movement of the second guide rod 42B in the vertical direction Z. By using the linear bearings 47A and 47B, the movement of the guide rods 42A and 42B in the vertical direction Z can be smoothly guided, and positional deviations of the guide rods 42A and 42B in the horizontal direction X and the front-back direction Y can be suppressed.

[0063] The adjusting hole 41d is located at the center of the main part 41a in the left-right direction X. The adjusting hole 41d penetrates the main part 41a in the up-down direction Z. A spiral protrusion is formed on the inner peripheral surface of the adjusting hole 41d. This protrusion engages with the outer peripheral surface of the body part 46b of the adjusting screw 46 (details are described later).

[0064] like Figure 3 As shown, the mirror aperture 41e opens on the front surface of the main part 41a. A first mirror 61 (details described later) of the optical part 60 is inserted into the mirror aperture 41e. Thus, the first mirror 61 is fixed to the mirror aperture 41e. The shape of the mirror aperture 41e corresponds to the shape of the first mirror 61.

[0065] like Figure 4 As shown, the spring bushing 44 extends in the left-right direction X. A pair of through holes 44aA and 44aB are formed in the spring bushing 44 for inserting a pair of guide rods 42A and 42B. That is, the first guide rod 42A is inserted into the first through hole 44aA, and the second guide rod 42B is inserted into the second through hole 44aB.

[0066] The diameters of the through holes 44aA and 44aB are larger than the diameters of the guide rods 42A and 42B. Therefore, the guide rods 42A and 42B and the spring bushing 44 can move relative to each other in the vertical Z direction.

[0067] The force-applying part 45 applies a downward force to the second support part 20. In this embodiment, the force-applying part 45 includes a first helical spring 45A through which the first guide rod 42A is inserted and a second helical spring 45B through which the second guide rod 42B is inserted. However, the structure of the force-applying part 45 can be appropriately modified as long as it can apply a downward force to the second support part 20.

[0068] The inner diameters of the helical springs 45A and 45B are larger than the outer diameters of the guide rods 42A and 42B. Therefore, the guide rods 42A and 42B and the helical springs 45A and 45B can move relative to each other in the vertical Z-direction.

[0069] The adjusting screw 46 is screwed into the adjusting hole 41d of the base 41 from above. The adjusting screw 46 has a head 46a and a body 46b. The body 46b extends downward from the head 46a. The outer diameter of the head 46a is larger than the outer diameter of the body 46b and the inner diameter of the adjusting hole 41d.

[0070] A spiral protrusion is formed on the outer peripheral surface of the body portion 46b, which engages with the inner peripheral surface of the adjustment hole 41d. The body portion 46b is longer than the adjustment hole 41d. That is, the vertical dimension Z of the body portion 46b is larger than the vertical dimension Z of the adjustment hole 41d. Therefore, when the adjusting screw 46 is screwed in to a certain extent, the lower end of the body portion 46b protrudes downward from the lower surface of the base portion 41 and abuts against the upper surface of the spring bushing 44.

[0071] When the adjusting screw 46 is further tightened in this state, the lower end of the body part 46b compresses the coil springs 45A and 45B in the vertical Z direction via the spring bushing 44. As a result, the force exerted by the coil springs 45A and 45B (force-applying parts 45) on the second support part 20 increases. In other words, the elastic energy stored in the force-applying parts 45 increases. Thus, by adjusting the amount of tightening of the adjusting screw 46, the magnitude of the force exerted by the force-applying parts 45 on the second support part 20 (the elastic energy stored in the force-applying parts 45) can be adjusted.

[0072] like Figure 1 As shown, the mirror fixing part 48 is fixed to the lower end of the second guide rod 42B. The second mirror 62 of the optical part 60 is fixed to the lower end of the mirror fixing part 48 (details will be described later). Furthermore, as long as the illumination path R described later (refer to...) can be ensured... Figures 9A-9C Furthermore, by fixing the second mirror 62, the shape of the mirror fixing part 48 can be appropriately changed.

[0073] <Second support member 20, tweezers assembly 100, and restraining mechanism 52> like Figures 4-6B As shown, the second support portion 20 has a main body portion 21, an insertion portion 22, and a locking portion 23.

[0074] like Figure 4 as well as Figure 5 As shown, the main body 21 extends in the left-right direction X. A pair of fixing holes 21aA and 21aB are formed at both ends of the main body 21 in the left-right direction X. That is, the first fixing hole 21aA is located at the right end of the main body 21, and the second fixing hole 21aB is located at the left end of the main body 21.

[0075] like Figure 4 As shown, a pair of fixing holes 21aA and 21aB penetrate the main body 21 in the vertical direction Z. A pair of guide rods 42A and 42B are inserted into the fixing holes 21aA and 21aB, respectively. That is, a first guide rod 42A is inserted into the first fixing hole 21aA, and a second guide rod 42B is inserted into the second fixing hole 21aB.

[0076] Here, the first guide rod 42A is fixed to the inner circumferential surface of the first fixing hole 21aA, and the second guide rod 42B is fixed to the inner circumferential surface of the second fixing hole 21aB. Thus, the second support portion 20 is fixed to the pair of guide rods 42A and 42B. By fixing the second support portion 20 to both of the pair of guide rods 42A and 42B, the second support portion 20 effectively suppresses any shift in the relative position between the guide rods 42A and 42B.

[0077] Furthermore, as long as the guide rods 42A and 42B can be fixed, the shapes of the fixing holes 21aA and 21aB can be appropriately modified. For example, the first fixing hole 21aA may not penetrate the main body 21. More specifically, the first fixing hole 21aA may only open on the upper surface of the main body 21, and not on the lower surface of the main body 21.

[0078] like Figure 5 As shown, the insertion portion 22 is located at the right end of the main body portion 21. The insertion portion 22 according to this embodiment has a recess 22a that opens on the front surface and the upper surface of the main body portion 21. By forming such a recess 22a, a protrusion 22b is formed at the lower part of the recess 22a, protruding from the inner side (+Y side) of the recess 22a toward the near front side (-Y side).

[0079] The insertion portion 22 is the part of the second support portion 20 used to support the carrier mesh 110. In this embodiment, the second support portion 20 (insertion portion 22) indirectly supports the carrier mesh 110, which has been permeated with the sample solution, via the tweezers assembly 100. Hereinafter, the structure of the tweezers assembly 100 and the method of fixing the tweezers assembly 100 relative to the second support portion 20 (insertion portion 22) will be described.

[0080] like Figure 5 As shown, the tweezers assembly 100 involved in this embodiment includes tweezers 101, a strap 102, a mounting part 103, an intermediate body 104, and a cover 105.

[0081] The tweezers 101 have a pair of plates 101a and 101b. The upper ends of the plates 101a and 101b are connected to each other. The tweezers 101 supports the carrier net 110 by holding the carrier net 110 at the top ends of the plates 101a and 101b.

[0082] The belt 102 has a ring shape. Tweezers 101 are inserted into the belt 102. By inserting tweezers 101 into the belt 102, tweezers 101 are secured by the belt 102, and plates 101a and 101b are brought close to each other. Thus, the carrier net 110 is maintained in a state where it is held by the top ends of plates 101a and 101b.

[0083] The mounting part 103 is mounted on the upper end of the tweezers 101. The mounting part 103 has an upper side band 103a, a lower side band 103b, and a connecting part 103c.

[0084] The bands 103a and 103b have a ring shape. Tweezers 101 are inserted through the bands 103a and 103b. The bands 103a and 103b are arranged at predetermined intervals in the vertical direction Z. The lower band 103b is located below the upper band 103a. The connecting part 103c connects to the front (-Y side) end of the bands 103a and 103b.

[0085] The intermediate body 104 has a narrow portion 104c and a wide portion 104d connected to the front side (-Y side) of the narrow portion 104c. The narrow portion 104c and the wide portion 104d each have a generally cuboid shape. The lateral width (the dimension in the left-right direction X) of the wide portion 104d is greater than the lateral width of the wide portion 104d.

[0086] An insertion hole 104a is provided on the front surface of the wide portion 104d. The upper end of the tweezers 101, on which the mounting part 103 is mounted, is inserted into the insertion hole 104a.

[0087] Specifically, the insertion hole 104a includes an upper hole 104a1, a lower hole 104a2, and a middle hole 104a3. An upper band 103a is inserted into the upper hole 104a1. A lower band 103b is inserted into the lower hole 104a2. The portion of the tweezers 101 located between bands 103a and 103b is inserted into the middle hole 104a3.

[0088] Here, the lateral width (dimension in the left-right direction X) of the upper hole 104a1 is approximately equal to the lateral width of the upper band 103a, and the lateral width of the lower hole 104a2 is approximately equal to the lateral width of the lower band 103b. As a result, the tweezers 101 are fixed relative to the intermediate body 104 in a state where the displacement in the left-right direction X is suppressed.

[0089] The lateral width of the intermediate hole 104a3 is smaller than the lateral width of the upper band 103a. Therefore, when the upper band 103a is inserted into the upper hole 104a1, the lower surface of the upper band 103a abuts against the step portion between the upper hole 104a1 and the intermediate hole 104a3. Thus, the tweezers 101 are fixed relative to the intermediate body 104 in a state where displacement in the vertical direction Z is suppressed.

[0090] Grooves 104e extending in the vertical direction Z are formed on both sides of the wide portion 104d. In the illustrated example, the grooves 104e are not open on either the upper or lower surface of the wide portion 104d.

[0091] A slit 104b is provided in the narrow portion 104c, with openings on the rear surface and both sides of the narrow portion 104c. A protrusion 22b of the second support portion 20 is inserted into the slit 104b. If the protrusion 22b is inserted into the slit 104b, the portion of the narrow portion 104c located above the slit 104b is inserted into the recess 22a of the second support portion 20.

[0092] Here, the lateral width (dimension in the left-right direction X) of the narrow portion 104c is approximately equal to the lateral width of the recess 22a of the second support portion 20. Therefore, the intermediate body 104 is fixed relative to the second support portion 20 in a state where displacement in the left-right direction X is suppressed. The vertical dimension (Z) of the slit 104b is approximately equal to the vertical dimension (Z) of the protrusion 22b of the second support portion 20. Therefore, the intermediate body 104 is fixed relative to the second support portion 20 in a state where displacement in the vertical direction Z is suppressed.

[0093] The cover 105 covers the wide portion 104d of the intermediate body 104 when the tweezers 101 are inserted into the intermediate body 104. Specifically, the cover 105 has a front plate 105a that covers the front surface of the wide portion 104d and a pair of side plates 105b that cover both sides of the wide portion 104d. By having the front plate 105a cover the front surface of the wide portion 104d, the tweezers 101 is fixed relative to the intermediate body 104 in a state where displacement in the front-rear direction Y is suppressed.

[0094] Each side plate 105b has an upper protrusion 105c and a lower protrusion 105d. The upper protrusion 105c and the lower protrusion 105d protrude from the inner side surface of the side plate 105b in the left-right direction X toward the inner side in the left-right direction X. The upper protrusion 105c extends downward along the inner edge of the side plate 105b from the corner located at the upper end and inner end (+Y end) of the side plate 105b. The lower protrusion 105d extends upward from the lower central portion of the side plate 105b.

[0095] When the cover 105 covers the wide portion 104d, the upper protrusion 105c engages with the step portion between the narrow portion 104c and the wide portion 104d. When the cover 105 covers the wide portion 104d, the side plate 105b is inserted into the groove 104e of the wide portion 104d. Thus, the cover 105 is fixed to the intermediate body 104.

[0096] Thus, according to the insertion part 22 and the tweezers assembly 100 of this embodiment, the tweezers 101 supporting the carrier net 110 can be supported on the second support part 20 in a state that suppresses the offset and vibration relative to the second support part 20.

[0097] like Figure 6A as well as Figure 6BAs shown, the engaging portion 23 protrudes rearward from the main body portion 21. The engaging portion 23 has an engaging surface 23a facing downward. The rear surface of the engaging portion 23 is an inclined surface 23b. The inclined surface 23b is inclined in a manner that it faces forward as it faces upward.

[0098] The engaging part 23 is used to restrict the movement of the second support part 20 by means of the restricting mechanism 52. Hereinafter, the structure of the restricting mechanism 52 and the method by which the restricting mechanism 52 restricts the movement of the second support part 20 will be described.

[0099] The limiting mechanism 52 in this embodiment has a second magnetic attraction part 52a and a second attraction body 52b.

[0100] The second attractor 52b is a cylindrical conductor extending in the front-rear direction Y. In the illustrated example, the top surface of the second attractor 52b is an inclined surface 52c. The inclined surface 52c, like the inclined surface 23b of the engaging portion 23, is inclined in a manner that it faces forward as it faces upward.

[0101] The second magnetic attraction part 52a is driven by an electric current, such as Figure 6A as well as Figure 6B As shown, the second attractor 52b is magnetically attracted towards the rear (-Y direction). The second magnetic attractor 52a can also be, for example, a solenoid coil. The second magnetic attractor 52a is fixed to the bracket 30 (post 32) by a fixing element 52d (see reference). Figure 1 ).

[0102] The limiting mechanism 52 may also have a force-applying body (not shown) that applies a force to the second attracting body 52b in the forward (+Y direction). In this case, by stopping the current flowing in the second magnetic attraction section 52a, the force of the force-applying body can be used to return the magnetically attracted second attracting body 52b to its original position. Figure 6A (The location shown).

[0103] like Figure 6A As shown, when the second magnetic attraction part 52a does not magnetically attract the second attraction body 52b, the upper surface of the second attraction body 52b abuts against the engagement surface 23a of the engagement part 23.

[0104] Here, as described above, the guide rods 42A, 42B and the second support portion 20 fixed thereto can move relative to the base 41 fixed to the bracket 30 in the vertical direction Z (see also...). Figure 4 Therefore, in the case where the second attractor 52b does not abut against the engaging surface 23a (see reference...) Figure 6B The second support 20 of the tweezers assembly 100 (carrier net 110) moves downward (falls) under the influence of gravity (see also...). Figure 4The force-applying part 45, as described above, promotes the movement (falling) of the second support part 20 by applying a downward force to it.

[0105] That is, when the second magnetic attraction part 52a does not magnetically attract the second attraction body 52b, the second attraction body 52b engages with the engagement part 23 by abutting its upper surface against the engagement surface 23a, thereby restricting the movement of the second support part 20 (see reference). Figure 6A Furthermore, the second magnetic attraction part 52a is driven by an electric current, thereby magnetically attracting the second attraction body 52b in a manner that releases the engagement (see reference). Figure 6B Furthermore, in order to ensure smooth sliding between the engaging surface 23a and the second attractor 52b at this time, the engaging surface 23a is preferably formed of a material with a low coefficient of friction (e.g., polytetrafluoroethylene).

[0106] Thus, according to the limiting mechanism 52 and the guide portion 40 of this embodiment, by controlling the current flowing in the second magnetic attraction portion 52a, the second support portion 20 can be moved (dropped) toward the freezing container 130 (freezing space S) at any time. In particular, according to the guide portion 40 of this embodiment, the dropping position of the second support portion 20 can be guided with high precision by the linear bearings 47A, 47B and the guide rods 42A, 42B (see reference). Figure 4 ).

[0107] In this specification, the limiting mechanism 52 and the guide 40, which are capable of moving the second support 20 at any time, are sometimes collectively referred to as the "moving mechanism". The moving mechanism moves the second support 20 so that the netting 110 moves toward the freezing space S of the freezing container 130 (see also...). Figure 1 Furthermore, the current flowing in the second magnetic attraction section 52a is controlled by the control section 70 (details are described later).

[0108] In addition, the second support 20, which had been temporarily lowered, was returned to its original position. Figure 6A In the case of the position shown, firstly, the current flowing in the second magnetic attraction section 52a is stopped. Next, for example, the operator lifts the handle 43, thereby moving the second support section 20 upwards (see also...). Figure 4When the second support 20 moves upward to a certain extent, the inclined surface 23b of the engaging part 23 abuts against the inclined surface 52c of the second suction body 52b. When the second support 20 is moved upward further in this state, the inclined surface 23b of the engaging part 23 overcomes the force of the applying body and presses the inclined surface 52c of the second suction body 52b backward (in the +Y direction). This allows the second suction body 52b to temporarily retract backward. When the second support 20 is moved upward further, the inclined surfaces 23b and 52c separate, and the second suction body 52b returns to its original position due to the force of the applying body. Finally, the operator releases the handle 43, thereby returning the second support 20 to its original position.

[0109] <First Support Section 10 and Retreat Mechanism 51> like Figure 7 As shown, the first support portion 10 in this embodiment has an extension portion 11 and a rotating portion 12.

[0110] The extension 11 extends in the front-rear direction Y. Hereinafter, the top end (-Y end) of the extension 11 will be referred to as the top end 11a, and the rear end (+Y end) of the extension 11 will be referred to as the base end 11b. A forward-facing abutment surface 11c is provided at the front end 11a.

[0111] At least one (two in the illustrated example) threaded hole H2a is formed at a distance from each other in the front-rear direction Y. The threaded hole H2a extends through the portion 11 in the vertical direction Z.

[0112] The rotating part 12 is connected to the extension 11 via a rotating shaft 13 in a manner that allows it to rotate relative to the top end 11a of the extension 11. Furthermore, the rotating shaft 13 is located near the right side of the extension 11 and extends in the vertical direction Z. The rotating part 12 has an abutting surface 12b that abuts against the abutting surface 11c of the extension 11. By rotating the rotating part 12, the angle formed by the abutting surfaces 11c and 12b varies within a range of 0° to a predetermined angle α (α > 0°).

[0113] A mounting hole 12a for mounting filter paper 120 is formed in the rotating part 12. The mounting hole 12a faces to the left when the angle formed by the abutting surfaces 11c and 12b is 0°. Thus, the filter paper 120 mounted in the mounting hole 12a is opposite the carrier mesh 110 supported by the second support part 20 and the tweezers assembly 100 in the left-right direction X (see reference). Figure 1 ).

[0114] In this embodiment, when viewed from the screen 110, the filter paper 120 (first support portion 10) is disposed on one side (right side). That is, when viewed from the screen 110, the filter paper 120 (first support portion 10) is not disposed on the other side (left side).

[0115] like Figure 7 As shown, the retraction mechanism 51 of this embodiment has a first magnetic attraction part 51a, at least one (two in the illustrated example) first attractor 51b and a connecting part 51c.

[0116] The first attractor 51b is a columnar conductor extending in the left-right direction X. In the illustrated example, the retraction mechanism 51 has two first attractors 51b arranged at intervals in the front-back direction Y.

[0117] The first magnetic attraction part 51a is driven by an electric current to magnetically attract the first attraction body 51b to the right. The first magnetic attraction part 51a may, for example, be two solenoid coils arranged corresponding to the two first attraction bodies 51b.

[0118] The retraction mechanism 51 may also have a force-applying body (not shown) that applies a force to the first attracting body 51b toward the left. In this case, by stopping the current flowing in the first magnetic attracting part 51a, the force of the force-applying body can be used to return the magnetically attracted first magnetic attracting part 51a to its original position. Figure 9A (The location shown).

[0119] The connecting part 51c connects the first support part 10 and the first attractor 51b. More specifically, in the example shown in the figure, the connecting part 51c has an upper plate 51d, a front plate 51e, and a rear plate 51g, and has an upwardly convex U-shaped shape when viewed from the front-rear direction Y.

[0120] The rear plate 51g is located to the right of the first magnetic attraction part 51a. The rear plate 51g extends along the vertical direction Z and the front-back direction Y. The rear plate 51g extends downward from the right end of the upper plate 51d.

[0121] The upper plate 51d is located above the first magnetic attraction part 51a. The upper plate 51d extends in the left-right direction X and the front-back direction Y. At least one threaded hole H2b is formed on the upper surface of the left end of the upper plate 51d, which is arranged at intervals in the front-back direction Y.

[0122] Screw SC2 is screwed into threaded hole H2b through threaded hole H2a, thereby fixing the extension 11 of the first support portion 10 to the upper plate 51d. Furthermore, since it is configured to change the fixed position of the first support portion 10 relative to the connecting portion 51c in the front-rear direction Y, in the illustrated example, the number of threaded holes H2b is greater than the number of threaded holes H2a.

[0123] The front plate 51e is located to the left of the first magnetic attraction part 51a. The front plate 51e extends along the vertical direction Z and the front-back direction Y. The front plate 51e extends downward from the left end of the upper plate 51d. At least one (two in the illustrated example) connecting hole 51f is formed at the lower end of the front plate 51e, which are spaced apart in the front-back direction Y.

[0124] A connecting hole 51f passes through the front plate 51e in the left-right direction X. A first suction body 51b is inserted into and fixed in each connecting hole 51f. Thus, the connecting part 51c and the first support part 10 fixed to the connecting part 51c and the first suction body 51b move in the left-right direction X in a coordinated manner. In addition, in order to suppress the relative rotation of the connecting part 51c (first support part 10) with respect to the first suction body 51b about the connecting hole 51f (first suction body 51b) as the axis of rotation, two connecting holes 51f (first suction bodies 51b) are arranged side by side in the front-back direction Y.

[0125] More specifically, when the first magnetic attraction part 51a is not magnetically attracting the first attracting body 51b, the second support part 20 is located Figure 8A The removal position is shown. The "removal position" is the location where the filter paper 120 can remove the sample solution from the screen 110. In this embodiment, more specifically, the "removal position" is the position where the filter paper 120 contacts the screen 110. Additionally, in... Figures 8A-8C The diagram of the connecting part 51c has been omitted for ease of observation.

[0126] Furthermore, when the first magnetic attraction part 51a magnetically attracts the first attraction body 51b, the first attraction body 51b is linked with the first support part 10, thereby causing the first support part 10 to retract to the right from the removal position (see reference). Figure 8B In this way, the retraction mechanism 51 retracts the first support 10 from the removal position.

[0127] In the sample freezing apparatus 1 according to this embodiment, the filter paper 120 can be separated from the wire mesh 110 even without activating the retraction mechanism 51. Specifically, by rotating the rotating part 12 about the rotation axis 13 such that the contact surfaces 11c and 12b are separated from each other, the filter paper 120 can be separated from the wire mesh 110 (see reference). Figure 8C Therefore, the sample solution can be injected not only from the left side of the carrier net 110, but also from the right side.

[0128] The position of the first magnetic attraction part 51a can also be adjusted relative to the support 30. Specifically, as shown in the figure... Figure 1As shown, the sample freezing device 1 may also have an adjustment mechanism 53 (e.g., a micrometer) for adjusting the position of the first magnetic attraction part 51a. For example, the adjustment mechanism 53 may also have a fixing plate 53a for fixing the first magnetic attraction part 51a and a drive part 53b for adjusting the position of the fixing plate 53a.

[0129] According to this adjustment mechanism 53, the position of the second support 20 connected to the first attractor 51b can be adjusted. This allows for adjustment of the relative position of the filter paper 120 and the carrier screen 110. Furthermore, the first magnetic attractor 51a can, for example, be fixed to the bracket 30 (bottom 31).

[0130] <Optics Section 60> like Figure 1 as well as Figures 9A-9C As shown, the optical section 60 has a first mirror 61 and a second mirror 62.

[0131] like Figures 9A-9C As shown, the first mirror 61 is fixed to the base 41 of the guide portion 40. More specifically, the first mirror 61 is fixed to the mirror hole 41e of the base 41 (see reference). Figure 3 The second mirror 62 is fixed to the mirror fixing part 48 of the guide part 40.

[0132] With the first mirror 61 fixed to the base 41, the reflecting surface 61a of the first mirror 61 is tilted to the right as it faces downward. More specifically, the first mirror 61 is fixed to the base 41 with the reflecting surface 61a tilted at approximately 45° relative to the vertical direction Z. As a result, the first mirror 61 reflects light incident from the left downward.

[0133] With the second mirror 62 fixed to the mirror fixing part 48, the reflective surface 62a of the second mirror 62 is tilted to the right as it faces downward. More specifically, the second mirror 62 is fixed to the mirror fixing part 48 with the reflective surface 62a tilted at approximately 45° relative to the vertical direction Z. As a result, the second mirror 62 reflects light incident from above to the right.

[0134] With mirrors 61 and 62 fixed to the guide portion 40 (base 41 and mirror fixing portion 48), the first mirror 61 (reflecting surface 61a) and the second mirror 62 (reflecting surface 62a) are arranged in the vertical direction Z. With the second mirror 62 fixed to the mirror fixing portion 48, the second mirror 62 (reflecting surface 62a) and the carrier net 110 are arranged in the horizontal direction X.

[0135] The light source 140 is used when positioned to the left of the first mirror 61. When the light source 140 illuminates light to the right in this state, the light is reflected by mirrors 61 and 62 and reaches the grid 110. That is, the optical unit 60 changes the direction of light travel (reflection) of the light from the light source 140 so that the light illuminating the grid 110 is directed to the grid. In other words, the optical unit 60 generates an illumination path R that allows light to be irradiated from the light source 140 onto the grid 110. The light source 140 may, for example, be a laser light source.

[0136] As described above, in the sample freezing apparatus 1 according to this embodiment, the second support 20 moves downward (falls) by the action of the moving mechanism (limiting mechanism 52 and guide part 40). Here, the mirror fixing part 48 is connected to the second support 20 via guide rods 42A and 42B. Therefore, as Figures 9A-9C As shown, the second mirror 62, which is fixed to the mirror fixing part 48, moves (falls) along with the second support part 20 during the movement (falling) described above. That is, the relative position of the second mirror 62 (reflective surface 62a) and the carrier net 110 is maintained from before the movement (before falling) of the second support part 20 to after the movement (after falling).

[0137] Therefore, an irradiation path R that allows light to be irradiated from the light source 140 to the grid 110 is maintained from before (before) the second support 20 moves (before) to after (after) its movement. Thus, for example, light can be irradiated from the light source 140 to the grid 110 at any time during the period from when the sample solution penetrates the grid 110 supported by the second support 20 until the grid 110 enters the freezing space S.

[0138] Furthermore, to prevent damage to the second mirror 62 when the carrier net 110 enters the freezing space S, it is desirable to appropriately design the shape of the mirror fixing part 48. More specifically, the shape of the mirror fixing part 48 can be designed so that the mirror fixing part 48 or the second mirror 62 does not come into contact with the freezing container 130 when the second support part 20 ends its movement (falling). For example, the shape of the mirror fixing part 48 can be designed so that the mirror fixing part 48 and the second mirror 62 are located within the recess 131 of the freezing container 130 when the second support part 20 ends its movement (falling).

[0139] <Control Department 70> The control unit 70 controls the movement mechanism (limiting mechanism 52 and guide unit 40) and the limiting mechanism 52 (see reference). Figure 1 The control unit 70 in this embodiment controls the current flowing in the magnetic attraction units 51a and 52a.

[0140] More specifically, the control unit 70 in this embodiment controls the retraction of the first support portion 10 by the retraction mechanism 51 and the movement of the second support portion 20 by the moving mechanism, so that the cooling standby time T is less than 1 second. Furthermore, more preferably, the control unit 70 controls the retraction of the first support portion 10 by the retraction mechanism 51 and the movement of the second support portion 20 by the moving mechanism, so that the cooling standby time T is less than 0.5 seconds. Here, "cooling standby time T" is defined as the time from the retraction of the first support portion 10 from the removal position (see reference...). Figure 8A as well as Figure 8B Until the carrier network 110 enters the frozen space S (refer to...) Figures 9A-9C (Time)

[0141] The control unit 70 can be implemented using a computer such as a microcomputer, personal computer, or workstation. When the control unit 70 is implemented by a computer, its functions are achieved by the CPU (Central Processing Unit) of the computer executing a program to perform those functions. That is, the functions of the control unit 70 are achieved through the collaboration of software and hardware resources. Alternatively, the control unit 70 can also be implemented using hardware such as FPGA (Field-Programmable Gate Array), LSI (Large Scale Integration), or ASIC (Application Specific Integrated Circuit).

[0142] <Effects> Next, the effect of the sample freezing device 1 configured as described above will be explained.

[0143] Previously, a sample solution freezing apparatus as described in Non-Patent Document 1 was known. According to the experimental results of the inventors of this application, it is sometimes difficult to freeze the sample in the desired state using the sample solution freezing apparatus described in Non-Patent Document 1. More specifically, it is known that in the sample solution freezing apparatus described in Non-Patent Document 1, the sample is frozen in a specific orientation, making it difficult to freeze the sample in various orientations.

[0144] Figure 10 It is an image (specifically, a two-dimensional averaged image) obtained by photographing a sample 113 frozen by the sample freezing apparatus described in Non-Patent Document 1. Specifically, a sample solution containing multiple samples 113 is frozen using the sample freezing apparatus of Non-Patent Document 1, and the frozen sample solution is photographed. Figure 10 The 14 images shown represent average images of 14 different aggregates of sample 113 contained in the frozen sample solution. Furthermore, the sample 113 used in this experiment consists of protein particles.

[0145] like Figure 10 As shown, the 14 images of sample 113 show samples oriented in almost the same direction. This means it is difficult to observe sample 113 three-dimensionally from the images obtained from this experiment. Furthermore, even after repeated freezing of the sample solution, sample 113 remains oriented in roughly the same direction, making three-dimensional observation of sample 113 still difficult. Thus, the inventors of this application have clarified that it is sometimes difficult to perform three-dimensional structural analysis of sample 113 based on the sample solution frozen using the sample freezing device of Non-Patent Document 1. In this experiment, the cooling standby time T in the sample freezing device of Non-Patent Document 1 is greater than 1 second. Specifically, the cooling standby time T in the sample freezing device of Non-Patent Document 1 is approximately 3 to 4 seconds.

[0146] Figure 11 This refers to an image (specifically, a two-dimensional averaged image) obtained by capturing a sample 113 frozen by the sample freezing apparatus 1 according to this embodiment. Specifically, a sample solution containing multiple samples 113 is frozen using the sample freezing apparatus 1 according to this embodiment, and the frozen sample solution is then captured on image. Figure 11 The results of the experiment are shown when the cooling standby time T is set to less than 1 second. Figure 11 The 14 images shown represent the average image of 14 different groups of sample 113 contained in the frozen sample solution. Furthermore, the sample 113 used in this experiment is the same as that in... Figure 10 The experiment used sample 113, which contained particles of the same protein.

[0147] like Figure 11 As shown in the 14 images, the sample 113 is oriented in various directions. Thus, the inventors of this application have demonstrated through experiments that by shortening the cooling standby time T (specifically, set to less than 1 second), it is possible to freeze the sample solution with the sample 113 oriented in various directions. Figures 12A-12C A three-dimensional model of specimen 113, obtained through three-dimensional structural analysis based on images obtained in this experiment, is shown. Figures 12A-12C As shown, the inventors of this application successfully fabricated a three-dimensional model of sample 113 using a sample freezing device 1 with a cooling standby time T of less than 1 second. Furthermore, Figures 12A-12C The three-dimensional model shown was obtained through the initial freezing of the sample freezing device 1.

[0148] The following examines the main reasons why the sample 113 can be observed from various orientations by shortening the cooling standby time T. Before the operator allows the sample solution to penetrate the carrier mesh (penetration section), the sample solution is stored in a designated container. At this time, the sample solution has sufficient volume to negate the effects of surface tension and forces caused by evaporation on the sample 113. However, the volume of the sample solution dispensed from the container and held in the carrier mesh (penetration section) becomes very small compared to when it was stored in the container. Therefore, it is believed that in the sample solution held in the carrier mesh, the surface tension and forces caused by evaporation of the sample solution act on the sample 113. Moreover, it is believed that through these forces, the orientation of the sample 113 gradually unifies towards the same orientation. Shortening the cooling standby time T means shortening the time these forces act on the sample 113. Therefore, it is believed that by shortening the cooling standby time T, it is possible to observe the sample 113 from various orientations. Figure 11 The sample 113 was observed from all directions, just like in the experiment.

[0149] As described above, in the sample solution freezing apparatus described in Non-Patent Document 1, the cooling standby time T is greater than 1 second. However, during this cooling standby time T, the sample solution from the carrier may evaporate, and the state (humidity, etc.) of the sample solution may change. Therefore, it is sometimes difficult to freeze the sample in the desired state. Furthermore, in Non-Patent Document 1, a humidification chamber is provided to prevent the evaporation of the sample solution, which houses the entire sample freezing apparatus 1.

[0150] The inventors of this application conducted in-depth research and found that in the sample solution freezing device described in Non-Patent Document 1, it is difficult to set the cooling standby time T to less than 1 second. The reason is that in that device, a motor-driven arm is used as a retraction mechanism to retract the filter paper from the carrier wire, and the movement of this arm is relatively slow.

[0151] To address this issue, the sample freezing apparatus 1 according to this embodiment allows the cooling standby time T to be set to 1 second or less. Therefore, compared to conventional apparatuses, the sample freezing apparatus 1 according to this embodiment makes it easier to freeze the sample in the desired state. In particular, a structure with a cooling standby time T of 0.5 seconds or less is preferred in terms of making it easier to freeze the sample in the desired state. Since the shortened cooling standby time T (1 second or less or 0.5 seconds or less) suppresses changes in the sample's state, a humidification chamber as in Non-Patent Document 1 is unnecessary. Therefore, miniaturization of the sample freezing apparatus 1 is also possible.

[0152] The cooling standby time T is affected by the retreat time t1 and the movement time t2. Here, "retreat time t1" is defined as the time from when the first support 10 begins to retreat from the removal position until the retreat of the first support 10 ends (the magnetic attraction of the first magnetic attraction part 51a ends). "Movement time t2" is defined as the time from when the second support 20 begins to move (fall) (from when the restriction of the restriction mechanism 52 is released) until the carrier net 110 enters the freezing space S.

[0153] In the sample freezing apparatus 1 according to this embodiment, the limiting mechanism 52 for retracting the filter paper 120 (first support 10) uses a first magnetic attraction part 51a that can be controlled at high speed. As a result, compared with the apparatus of Non-Patent Document 1 that uses a motor-driven arm, the retraction time t1 can be shortened (specifically, preferably 0.3 seconds or less, more preferably 0.1 seconds or less). As a result, the cooling standby time T can be shortened.

[0154] Similarly, in the sample freezing apparatus 1 according to this embodiment, the moving mechanism that moves the carrier net 110 (second support 20) uses a second magnetic attraction part 52a that can be controlled at high speed. As a result, the moving time t2 can be shortened (specifically, to a few hundred milliseconds or less, more preferably to 50 milliseconds or less). As a result, the cooling standby time T can be shortened.

[0155] Furthermore, the control unit 70 can also control the retraction mechanism 51 and the moving mechanism, so that the movement of the second support 20 by the moving mechanism begins before the retraction of the filter paper 120 by the retraction mechanism 51 is completed. That is, the retraction time t1 and the moving time t2 can also be repeated.

[0156] For example, in the case of a sample whose state changes over time by irradiation, it is sometimes desirable to irradiate the sample with light at any time before freezing. In the apparatus of Non-Patent Document 1, the arms supporting the filter paper are arranged on both sides of the support mesh, and the entire apparatus is covered by a humidification chamber (described later). Therefore, it is difficult to irradiate the sample solution held on the support mesh with light in the apparatus.

[0157] In contrast, in the sample freezing apparatus 1 according to this embodiment, the filter paper 120 (first support portion 10) is only provided on one side when viewed from the screen 110. Furthermore, in the sample freezing apparatus 1 according to this embodiment, no chamber covering the sample freezing apparatus 1 is provided. Therefore, for example, light can be irradiated onto the screen 110 from the light source 140 via the optical unit 60.

[0158] Furthermore, in the sample freezing apparatus 1 according to this embodiment, the irradiation path R is maintained throughout the movement (falling) of the carrier net 110. Therefore, for example, light can be irradiated from the light source 140 onto the carrier net 110 at any time during the period from when the sample solution penetrates into the carrier net 110 supported on the second support 20 until the carrier net 110 enters the freezing space S. As a result, it is possible to smoothly observe the sample whose state changes over time due to light.

[0159] Summary As described above, the sample freezing apparatus 1 according to this embodiment includes: a first support 10 supporting filter paper 120 (removal section) for removing excess sample solution 114 from a carrier mesh 110 (infiltration section) in which sample solution 114 has been infiltrated; a retraction mechanism 51 for retracting the first support 10 from a removal position where the filter paper 120 can remove sample solution 114 from the carrier mesh 110; a second support 20 supporting the filter paper 120; a moving mechanism (limiting mechanism 52 and guiding section 40) for moving the second support 20 so that the carrier mesh 110 enters the freezing space S for freezing the sample solution 114; and a control unit 70 for controlling the retraction mechanism 51 and the moving mechanism, wherein the control unit 70 controls the retraction of the first support 10 by the retraction mechanism 51 and the movement of the second support 20 by the moving mechanism so that the time (cooling standby time T) from the time the first support 10 retracts from the removal position until the carrier mesh 110 enters the freezing space S is 1 second or less.

[0160] Based on this structure, a sample freezing device 1 can be provided that can easily freeze the sample in the desired state.

[0161] The retraction mechanism 51 includes: a first attracting body 51b that moves in conjunction with the first support portion 10; and a first magnetic attracting portion 51a that is driven by an electric current to magnetically attract the first attracting body 51b, and a control unit 70 that controls the current flowing in the first magnetic attracting portion 51a. With this structure, the retraction time t1 can be shortened. Therefore, a cooling standby time T of less than 1 second can be easily achieved.

[0162] The moving mechanism includes: a second attracting body 52b that engages with a second support portion 20 to restrict movement of the second support portion 20; and a second magnetic attracting portion 52a that magnetically attracts the second attracting body 52b to release the engagement between the current-driven second attracting body 52b and the second support portion 20. A control unit 70 controls the current flowing in the second magnetic attracting portion 52a. With this structure, the moving time t2 can be shortened. Therefore, a cooling standby time T of less than 1 second can be easily achieved.

[0163] The moving mechanism has a force-applying part 45 for facilitating the movement of the second support 20. According to this structure, the moving time t2 can be further shortened.

[0164] The filter paper 120 is positioned on one side when viewed from the screen 110. This structure makes it easy to achieve a structure that allows light to be irradiated from the light source 140 onto the screen 110.

[0165] The sample freezing apparatus 1 according to this embodiment also includes an optical section 60, which changes the direction of light travel of the light source 140 so that light irradiated from the light source 140 is irradiated onto the carrier grid 110. With this structure, light can be easily irradiated from the light source 140 onto the carrier grid 110.

[0166] As the carrier net 110 moves toward the frozen space S via the moving mechanism, at least a portion of the optical section 60 (the second mirror 62) moves along with the carrier net 110. With this structure, the illumination path R is always maintained during the movement (falling) of the carrier net 110, thus enabling light to be irradiated from the light source 140 onto the carrier net 110 at any time.

[0167] <Variation Example> Furthermore, the scope of the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

[0168] For example, the penetration section for allowing the sample solution to penetrate may not be the screen 110, and can be modified appropriately. Similarly, the removal section for removing excess sample solution may not be the filter paper 120, and can be modified appropriately.

[0169] As long as the positional relationship of each part of the sample freezing device 1 can be properly maintained, the sample freezing device 1 may not need to have a support 30.

[0170] The structure of the freezing container 130 can be appropriately modified as long as there is a freezing space S capable of freezing the sample solution 114. Alternatively, the freezing space S is not limited to the space set inside a container such as the freezing container 130, and can be appropriately modified.

[0171] As long as a cooling standby time T of less than 1 second can be achieved, the structures of the moving mechanism and the retraction mechanism 51 can be appropriately modified. For example, the moving mechanism can also be configured to move the guide rods 42A and 42B by a motor such as a linear motor. The moving mechanism can have a spring mechanism, an air injector, a wheel, or a high-speed electric stage, or a mechanism that utilizes the lever principle.

[0172] In the above embodiment, the second support portion 20 indirectly supports the carrier net 110 via the tweezers assembly 100, but the second support portion 20 may also be configured to directly support the carrier net 110.

[0173] As long as the illumination path R can be ensured, the structure of the optical unit 60 can be appropriately modified. For example, when the light source 140 is positioned above the second mirror 62 and the light source 140 illuminates downwards, the optical unit 60 may not have the first mirror 61. The optical unit 60 may also utilize the refraction of light to change the direction of light travel of the light source 140. Furthermore, for example, when using a sample that does not react to light, the sample freezing device 1 may not have the optical unit 60.

[0174] Furthermore, without departing from the spirit of the present invention, the constituent elements in the above embodiments can be appropriately replaced with known constituent elements, and the above embodiments and variations can also be appropriately combined.

[0175] Explanation of reference numerals in the attached figures 1. Sample freezing device; 10. First support part; 20. Second support part; 40. Guide part (moving mechanism); 45. Force application part; 51. Retreat mechanism; 51a. First magnetic attraction part; 51b. First attracting body; 52. Restriction mechanism (moving mechanism); 52a. Second magnetic attraction part; 52b. Second attracting body; 60. Optical part; 70. Control part; 110. Carrying net (penetration part); 114. Sample solution; 120. Filter paper (removal part); S. Freezing space.

Claims

1. A sample freezing device, wherein, The sample freezing device includes: A first support portion supports a removal portion for removing excess sample solution from an infiltration portion in which the sample solution has infiltrated. A retraction mechanism allows the first support to retract from the removal position where the sample solution can be removed from the penetration section; The second support portion supports the infiltration portion; A moving mechanism moves the second support portion so that the penetrating portion enters the freezing space that freezes the sample solution. as well as The control unit controls the retraction mechanism and the moving mechanism. The control unit controls the retreat of the first support unit by the retreat mechanism and the movement of the second support unit by the moving mechanism, so that the time from the retreat of the first support unit from the removal position until the infiltration part enters the frozen space is less than 1 second.

2. The sample freezing device according to claim 1, wherein, The retraction mechanism includes: a first attracting element that moves in conjunction with the first supporting portion; and a first magnetic attracting portion that is driven by an electric current to magnetically attract the first attracting element. The control unit controls the current flowing in the first magnetic attraction unit.

3. The sample freezing apparatus according to claim 1 or 2, wherein, The moving mechanism has: The second suction body engages with the second support portion to restrict the movement of the second support portion; The second magnetic attraction part, driven by an electric current, magnetically attracts the second attracting body to release the engagement between the second attracting body and the second support part. The control unit controls the current flowing in the second magnetic attraction unit.

4. The sample freezing apparatus according to claim 1 or 2, wherein, The moving mechanism has a force-applying part for facilitating the movement of the second support.

5. The sample freezing apparatus according to claim 1 or 2, wherein, The removal section is located on a single side when viewed from the penetration section.

6. The sample freezing apparatus according to claim 1 or 2, wherein, The sample freezing device also includes an optical section that changes the direction of light travel of the light source in such a way that light irradiated from the light source is directed to the penetration section.

7. The sample freezing apparatus according to claim 6, wherein, When the infiltration portion is moved toward the freezing space by the moving mechanism, at least a portion of the optical portion moves in tandem with the infiltration portion.

Images