JP2011036189A - Stirring device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stirring device capable of reducing the sheer force compared to a conventional device. <P>SOLUTION: The stirring device arranged in a cell culture vessel and carrying out the stirring by a stirring blade has sheer force-reducing protrusion parts having flexibility and attached to the edge side of the stirring blade at a prescribed interval so as to be parallel, and the sheer force caused by the rotation of the stirring blade is reduced by the sheer force-reducing protrusion parts bent by the rotation of the stirring blade. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a stirring device used in a cell culture tank.

  The mixing operation in the mixing tank is one of important operations in the chemical industry and the like. That is, in the field of foods, cosmetics, medicines, pharmaceuticals, paints, etc., mixing operations are utilized in various processes such as reaction, extraction, absorption, and mixing. For example, as one of the mixing operations, in an animal cell culture tank such as a bioreactor, the inside of the tank is agitated in order to uniformly mix bubbles and nutrients that are oxygen supply sources supplied into the tank. It has been broken.

  For example, as such an animal cell culture tank, the following Patent Document 1 discloses that a mixture of liquid and bubbles is improved by a wing having a relatively simple structure, and further, the bubble diameter is made finer than that of the conventional one. There has been disclosed a culture tank that can increase the amount of dissolved oxygen concentration by increasing the liquid contact area, increasing the amount of oxygen transferred from bubbles into the liquid.

  In such an animal cell culture tank, especially when the culture tank becomes large and the height in the vertical direction becomes high, in order to mix the inside of the tank more uniformly, a large axial flow is generated in the culture tank by stirring. It is necessary to obtain a high degree of mixing. In general, when it is desired to uniformly mix materials having a density difference, these materials are easily separated in the vertical direction due to the density difference. Therefore, it is necessary to generate a large axial flow in the mixing tank by stirring. In particular, in the case of solid-liquid mixing, since the density difference becomes large and the solid content tends to settle, it is further necessary to generate an axial flow by stirring and to stir the inside of the tank vertically by this axial flow.

  And in a mixing tank, in order to obtain a high degree of mixing, it is necessary to use a high performance thing as a stirring apparatus. In particular, in an animal cell culture tank, animal cells are destroyed / destroyed by a shearing force generated by a stirring blade of a stirring device. Therefore, it is necessary to measure a balance between stirring efficiency and shearing force. As such a stirring device, conventionally, a stirring device using a specially shaped stirring blade called an elephant ear type is known. The elephant ear type stirring blade has a relatively large shape, and can obtain high mixing performance at a low rotational speed. In addition, paddle type and propeller type stirring blades are known.

JP 2003-02222 A

  By the way, in a cell culture vessel such as a bioreactor in the above-described conventional technology, the cells are grown by stirring the internal medium and the cells contained in the medium by the rotation of the stirring blade. However, if the number of rotations at this time is low, the efficiency of cell proliferation decreases, but if the number of rotations is too high, the cells are damaged by shearing force, thereby preventing growth. Therefore, as described above, the balance between the stirring efficiency and the shearing force is measured by selecting an appropriate stirring blade from various shapes such as a paddle type and an elephant ear type as the stirring blade.

  However, when a larger axial flow has to be generated due to further enlargement of the cell culture tank, a large shear vortex has been generated by high rotation. Then, the cells are damaged by the shearing force caused by the shearing vortex, so that the culture efficiency is lowered.

  This invention is made | formed in view of the situation mentioned above, and aims at providing the stirring apparatus which can suppress a shear force more than before.

  In order to achieve the above object, in the present invention, as a first solving means related to a stirring device, a stirring device disposed in a cell culture tank and stirred by a stirring blade, having flexibility, A shearing force suppressing protrusion is attached to the edge of the stirring blade so as to be parallel to the edge of the stirring blade, and the shearing force suppressing protrusion is bent by the rotation of the stirring blade, thereby rotating the stirring blade. The means of suppressing the shearing force generated by is adopted.

  In the present invention, as the second solving means relating to the stirring device, in the first solving means, a means is adopted in which the surface of the shear force suppressing protrusion is configured by a curved surface.

  According to the present invention, the stirrer is a stirrer that is disposed in the cell culture tank and stirs with the stirrer blade, has flexibility, and is arranged in parallel at a predetermined interval on the edge of the stirrer blade. The shearing force suppressing protrusions are attached in this manner, and the shearing force suppressing protrusions are bent by the rotation of the stirring blade, thereby suppressing the shearing force generated by the rotation of the stirring blade.

  That is, in the stirring device, a shear vortex is generated in the vicinity of the edge of the stirring blade, but the flow rate of the shear vortex in the vicinity of the edge of the stirring blade is relieved by the shear force suppression protrusion. As described above, in the agitator, by easing the flow velocity of the shearing vortex, it is possible to suppress the destruction / death of the cells due to the shearing force, so that the cell culture efficiency can be improved.

It is sectional drawing which shows an example of the animal cell culture tank S provided with the stirring apparatus A which concerns on one Embodiment of this invention. It is an expansion perspective view of the stirring part 2 of the stirring apparatus A which concerns on one Embodiment of this invention.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The present embodiment relates to a stirring device that is disposed in an animal cell culture tank and stirs a culture solution in the animal cell culture tank.
First, a schematic configuration of the animal cell culture tank S provided with the stirring device A according to the present embodiment will be described with reference to FIG. FIG. 1 is a cross-sectional view showing an example of an animal cell culture tank S provided with a stirring device A according to this embodiment. In the drawings, the scale of each member is appropriately changed to facilitate recognition of each member.

  The animal cell culture tank S is used, for example, for the production of pharmaceutical antibodies, and cultivates animal cells by using various biocatalysts such as microorganisms, animals / plants, or enzymes isolated from these cells. Is what you do. That is, the animal cell culture tank S is for culturing animal cells while supplying the culture solution L with bubbles or nutrient sources as oxygen supply sources.

Such an animal cell culture tank S includes a stirrer A, a culture tank 11, an air diffuser 12 and a baffle plate 13 as shown in FIG. 1 in order to uniformly mix bubbles and nutrient sources. .
As shown in FIG. 1, the stirring device A includes a rotation drive shaft 1, a stirring unit 2, and a rotation drive means 3.

  The rotary drive shaft 1 is a columnar member, and the stirring unit 2 is fixed to the lower end (one end side). The rotary drive shaft 1 is connected to a rotary drive means 3 composed of a motor or the like via a link mechanism such as a gear on the one end side opposite to the one end to which the stirring unit 2 is attached. . The rotational drive shaft 1 is rotationally driven by the rotational drive means 3, and rotationally drives the agitating unit 2 with its own rotation.

  The stirring unit 2 is attached and fixed to the lower end portion of the rotary drive shaft 1, and is attached to the rotary drive shaft 1 and fixed to the mounting cylinder 2a, and a plurality of fixed cylinders fixed to the outer peripheral surface of the mounting cylinder 2a. It consists of (for example, four) paddle blades 2b (stirring blades). The mounting cylinder 2a is provided with a detent (not shown), and the lower side of the mounting cylinder 2a is fixed by a cap 2c.

  With such a configuration, the stirring unit 2 is integrally fixed to the rotation drive shaft 1 and rotates together with the rotation drive shaft 1. The agitating unit 2 is designed and arranged so that an axial flow generated by rotating on a surface orthogonal to the rotational drive shaft 1 is generated below the rotational drive shaft 1.

  Further, as shown in FIG. 2, a plurality of shear force suppressing protrusions 2 d are attached to the agitating unit 2 so as to be parallel to the side of the edge of the paddle blade 2 b with a predetermined interval. FIG. 2 is an enlarged perspective view of the stirring unit 2 of the stirring device A according to the present embodiment. In addition, the arrow in FIG. 2 has shown the rotation direction R of the stirring part 2. FIG.

  The shearing force suppressing protrusion 2d is made of an extremely thin member having flexibility and a thinness of a thread. In addition, it is preferable that the surface of the shearing force suppressing protrusion 2d is a curved surface in order to suppress the shearing force.

  The rotation drive means 3 is composed of a motor or the like, and is connected to the rotation drive shaft 1 via a link mechanism such as a gear. The rotation drive means 3 rotates the rotation drive shaft 1 at a preset rotation speed.

  As shown in FIG. 1, the stirring device A having such a configuration is arranged upright in the animal cell culture tank S so that the rotary drive shaft 1 is arranged along the vertical direction, and the upper end side thereof is animal cell culture. The culture tank 11 of the tank S is rotatably held and fixed. The stirring unit 2 is disposed at the bottom of the animal cell culture tank S.

  The culture tank 11 is a bottomed and cylindrical container and stores the culture solution L therein. In this culture tank 11, the rotary drive shaft 1 is rotatably held by a bearing (not shown), an air diffuser 12 is attached to the bottom surface of the inner wall, and a baffle plate 13 is attached to the side surface of the inner wall. The culture solution L contains cells to be cultured and includes bubbles (oxygen supply source) and nutrients necessary for culturing the cells.

  The air diffuser 12 is provided in the lower part of the culture tank 11 and supplies air bubbles G (oxygen supply source) into the culture tank 11, and includes a ring sparger 12a and a gas supply machine 12b. Yes. The ring sparger 12a is formed of a disk-shaped member that is hollow and has a large number of openings formed on the surface thereof, and injects air supplied from the gas supply machine 12b as bubbles G from the openings.

  The gas supply machine 12b is a pump that supplies air to the ring sparger 12a. The air diffuser 12 supplies the air G supplied from the gas supply device 12 b through the opening of the ring sparger 12 a, thereby supplying the bubbles G containing oxygen to the culture solution L in the culture tank 11.

  The baffle plate 13 is a belt-like flat plate provided to extend in four directions on the side surface of the inner wall of the culture tank 11 in the vertical direction. That is, the baffle plate 13 is provided on the inner wall of the culture tank 11 so as to extend in the vertical direction at positions (four locations) corresponding to an angle of 90 ° with respect to the rotational drive shaft 1. The lower end of the baffle plate 13 is set at a position slightly below the stirring unit 2, and the upper end of the baffle plate 13 is set at a position slightly above the draft of the culture medium L.

  In the animal cell culture tank S, by attaching the baffle plate 13 to the side surface of the inner wall of the culture tank 11, the rotational flow perpendicular to the axial flow collides with the baffle plate 13, so that the rotational flow is directly applied to the inner wall of the culture tank 11. It is possible to prevent the bubbles G from being released to the outside (upward) of the culture medium L through the inner wall when colliding.

Next, operation | movement of the animal cell culture tank S comprised in this way is demonstrated in detail. In addition, the animal cell culture tank S of this embodiment is provided with the control part not shown. And unless there is particular notice, the said control part controls the following operation | movement as a subject.
In the animal cell culture tank S, bubbles (oxygen supply source), nutrient sources, and the like are supplied into the culture solution L by the aeration means 12 and the nutrient source supply means (not shown). In the animal cell culture tank S, the stirring device A is driven in parallel with the supply of the bubbles G (oxygen supply source) by the aeration means 12 and the supply of the nutrient source by the nutrient source supply means. That is, in the agitator A, the agitation unit 2 is rotated via the rotation drive shaft 1 by driving the rotation driving means 3.

  Then, the agitating unit 2 generates an axial flow that flows toward the vertically lower side of the rotary drive shaft 1 by rotating the paddle blade 2 b on a plane orthogonal to the rotary drive shaft 1. Then, the axial flow in the culture tank 11 of the animal cell culture tank S flows vertically downward from the stirring unit 2 and then collides with the bottom surface of the inner wall of the culture tank 11, thereby vertically moving along the inner wall surface. It flows toward. In the culture tank 11 of the animal cell culture tank S, the bubbles G containing oxygen and the nutrient source are uniformly mixed into the culture liquid L by circulation of the flow of the culture liquid L by this axial flow.

  In the stirring unit 2, a shear vortex is generated in the vicinity of the edge of the paddle blade 2b by the rotation, but the flow velocity of the shear vortex in the vicinity of the side of the edge of the paddle blade 2b is relieved by the shear force suppressing protrusion 2d. That is, after the culture medium L collides with the paddle blade 2b by the rotation of the stirring unit 2, the flow velocity of the vortex generated by the culture medium L flowing behind the paddle blade 2b is attached to the side of the edge of the paddle blade 2b. The shearing force suppressing projection 2d is relaxed by bending. Thus, in the stirring apparatus A, the shearing force in the vicinity of the side edge of the paddle blade 2b can be suppressed by relaxing the flow velocity of the shearing vortex.

  In the stirring device A of the present embodiment as described above, a plurality of shear force suppressing protrusions 2d are attached to the side of the edge of the paddle blade 2b of the stirring unit 2 so as to be arranged in parallel at a predetermined interval. In the agitator A, a shear vortex is generated in the vicinity of the edge of the paddle blade 2b by the rotation, but the flow velocity of the shear vortex in the vicinity of the side of the edge of the paddle blade 2b is relieved by the shear force suppressing protrusion 2d. As described above, in the stirring device A, since the cells are prevented from being destroyed / destroyed by the shearing force by relaxing the flow velocity of the shear vortex, the cell culture efficiency can be improved. .

As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the said embodiment, For example, the following modifications can be considered.
(1) In the above embodiment, the shear force suppressing protrusion 2d is attached to the paddle blade 2b, but the present invention is not limited to this.

  For example, when the stirring unit 2 of the stirring device A is not a paddle blade 2b as a stirring blade but a propeller blade is attached as a stirring blade, a shearing force suppressing protrusion is attached to the edge of the propeller blade. Also good. Further, the present invention may be applied to a stirring device having a disc turbine blade and an elephant ear blade other than the paddle blade 2b and the propeller blade. That is, the present invention can be applied to any stirring device regardless of the shape.

(2) In the above-described embodiment, the shear force suppressing protrusion 2d is configured by an ultrathin member having a yarn-thickness, but the present invention is not limited to this.
For example, the shear force suppressing protrusion 2d may be a member having an area along the surface of the stirring blade, as long as it is a flexible member, even if it is not extremely thin like an extremely thin member. In this case as well, it is preferable that the surface of the shearing force suppressing protrusion 2d is configured by a curved surface as much as possible.

(3) In the above embodiment, the shear force suppressing protrusion 2d is attached to the side of the edge of the paddle blade 2b of the stirring unit 2, but the present invention is not limited to this.
For example, the shear force suppressing protrusions 2d may be attached to the upper side and the lower side of the edge of the paddle blade 2b. That is, according to the present invention, the shear force suppressing protrusion 2d may be attached to any of the edges of the stirring blade.

DESCRIPTION OF SYMBOLS S ... Animal cell culture tank, A ... Stirring apparatus, 1 ... Rotation drive shaft, 2 ... Stirring part, 2a ... Mounting cylinder, 2b ... Paddle blade, 2c ... Cap, 2d ... Shear force suppression protrusion part, 3 ... Rotation drive means 11 ... Culture tank, 12 ... Air diffuser, 12a ... Ring sparger, 12b ... Gas supply machine, 13 ... Baffle plate

Claims (2)

A stirrer arranged in a cell culture tank and stirred by rotation of a stirring blade,
Having a shearing force suppressing protrusion attached to the edge of the stirring blade so as to be parallel with a predetermined interval;
An agitation apparatus characterized in that the shearing force suppressing protrusion is bent by the rotation of the agitation blade, thereby suppressing the shearing force generated by the rotation of the agitation blade. The stirring device according to claim 1, wherein the surface of the shear force suppressing protrusion is configured by a curved surface.

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