JPS63101751A - Separation of plasma and apparatus used therefor - Google Patents

Abstract

PURPOSE:To prevent the lowering of separation efficiency, by rotating an outer cylinder with a separation film fixed to move blood cells outward with the action of a centrifugal force. CONSTITUTION:Blood is introduced into a space between a separation film 2 and an outer cylinder 3 through a piping 9 and the outer cylinder 3 is rotated at a high speed. Consequently, under receiving a centrifugal force, blood cells are moved to the surface of the outer cylinder 3. After the blood cells and plasma are separated roughly, the plasma builds up in an inner cylinder 1 with the separation film 2. The plasma in the inner cylinder 1 is taken out through a piping 10. The blood from which the plasma has been separated is take off through the piping 9. The blood cells and the plasma are separated roughly with the action of a centrifugal force on the blood cells to reduce the density of the blood cells on the surface of the film 2 and thus, the clogging of pores of the film 2 is prevented thereby eliminating a drop in the separation capacity.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a plasma separation method and an apparatus used therefor.

[Prior Art] Conventionally, centrifugation was the main method used to separate blood into plasma and formed components such as red blood cells and white blood cells (hereinafter simply referred to as blood cells). Membrane separation methods using separation membranes that do not allow blood cells to pass through are increasingly being adopted.

In the membrane separation method, if blood is simply allowed to flow through one side of the separation membrane, the micropores of the separation membrane will become clogged with blood cells, reducing filtration efficiency.To prevent this, shear force is applied to the flow of blood. There are known ways to do this.

For example, in Japanese Patent Application Laid-Open No. 59155758, a fixed outer cylinder is disposed coaxially with the rotational axis of the inner cylinder on the outer periphery of a rotating inner cylinder having a portion MwA on the peripheral wall surface, and blood is injected into the gap between the inner cylinder and the outer cylinder. It has been proposed to collect plasma into the inner cylinder through a separation membrane by rotating the inner cylinder at high speed while feeding. In this device, in order to apply a high shear force to the blood layer on the surface of the separation membrane, the gap between the separation membrane and the inner surface of the outer cylinder is set to 0.
25α or less, and the rotational speed of the inner cylinder is 11,000 rpm or more, and the formula:
The shear force (sec-1) expressed by the gap between the separation membrane and the inner surface of the outer cylinder is set to be 10005 ec-1 or more. More specifically, for example, the rotational speed of the inner cylinder is 3600rDI, d=0.06cm1 sea 80
The condition of 00 (sec-1) is adopted.

[Problems to be Solved by the Invention] However, in order to rotate the inner tube having a separation membrane at high speed with respect to the fixed outer cylinder in such a minute gap as described above, processing with an extremely high 1 fill K is required, and the separation membrane also has a high processing speed. It needs to be firmly fixed.

Furthermore, in the above device, the plasma collected in the rotating inner cylinder is taken out to the outside through a hole drilled in the bearing, so the sealing structure of the bearing becomes complicated.

When high shear force as described above is applied to blood,
There is a risk that red blood cells will come into contact with the separation membrane surface and cause excessive hemolysis.

The present invention has been made to address the above-mentioned problems and provide a plasma separation method and apparatus for use in the method, which can increase separation efficiency without applying high shear forces as in conventional methods, and which does not require a seal on the rotating shaft. be.

[Means for Solving the Problems] The present invention provides: (1) An outer cylinder rotatable coaxially with the central axis of the inner cylinder is provided on the outer periphery of a cylindrical fixed inner cylinder having a plasma separation membrane on the surface of the peripheral wall. A plasma separation method characterized in that blood is supplied to the gap between the valve 1IllIIa and the outer cylinder, the outer cylinder is rotated at high speed, and plasma is collected inwardly through the membrane 1IllIIa, and (a) a fixed cylindrical inner cylinder having a plasma separation membrane on its surface; a rotating outer cylinder rotatably disposed on the outer periphery of the inner cylinder coaxially with the central axis of the inner cylinder; and a rotating outer cylinder that rotates the rotating outer cylinder. an outer casing capable of supporting the outer casing, means for supplying blood into the gap between the separation membrane and the outer cylinder and removing blood from which plasma has been separated, and means for removing the separated plasma from the fixed inner cylinder; The present invention relates to a plasma separation device comprising a drive means for rotating the rotating external source at high speed.

[Function] When blood is put into the gap between the fixed separation membrane and the outer tube and the outer tube is rotated at high speed, centrifugal force acts on the blood cells and they move toward the surface of the outer tube. Since the concentration of blood cells in the blood layer becomes low and therefore no accumulation of blood cells occurs on the surface of the separation membrane, the separation efficiency does not decrease.

Since the inner cylinder is fixed, blood can be taken in and out and plasma can be taken out without going through the bearing.

[Example] Next, the present invention will be explained based on the drawings.

FIG. 1 is a schematic sectional view showing an embodiment of the plasma separation device of the present invention.

In FIG. 1, (1) is a cylindrical fixed cylinder, and a plasma separator 13+2) is provided on the peripheral wall (1a) of the internal chamber. An outer cylinder (3) is arranged on the outer periphery of the inner cylinder (1) and is rotatable coaxially with the central axis of the inner cylinder (1). An outer cylinder (3) housing the inner cylinder (1) is rotatably supported within the outer casing (4) via a bearing (51).

A rotary magnet (6) is fixed to the bottom wall (3b) of the outer cylinder (3), and a rotation induction magnet (7) corresponding to the rotary magnet (6) is attached to the outside of the outer casing (4). The rotation induction magnet (sword) is connected to a driving means such as an electric motor.By rotating the rotation induction magnet (7), the outer cylinder (3) is rotated at high speed.

By driving the outer cylinder (3) with magnetic force in this manner, a complete seal against the outside can be achieved.

A small diameter cylindrical part (1C) extends from the upper wall (1b) of the inner cylinder (1), and its tip is connected to the lid part (1C) of the outer casing (4).
4a). The earthen wall (3a) of the outer cylinder (3) has an opening through which the cylinder part (1C) of the inner cylinder (1) is inserted, and the cylinder part (1C) is inserted through the bearing (8).
).

(9) is a pipe for supplying blood to be processed and taking out blood that has been processed and has a high blood cell concentration;
9) is the outer casing (4) along the central axis of the inner cylinder (1).
), the lid part (4a) of the inner cylinder (1), the cylindrical part (1C) of the inner cylinder (1), the earthen wall (
1b), the bottom wall (1d) of the inner cylinder (1), and the bottom wall (1b) of the inner cylinder (1).
d) and the bottom wall (1b) of the outer cylinder (3). (G) is a piping for taking out plasma, and this piping extends along the central axis of the inner cylinder (1) to the vicinity of the bottom wall (1d) of the inner cylinder (1).

01) is a pipe for communicating the space between the separation 11 (2) and the outer cylinder (3) with the atmosphere.

Next, the operation of the device will be explained.

Separate blood through piping (9) I! (21 and outer cylinder (3)
and rotate the outer cylinder (3) at high speed.

Then, the blood cells in the blood move toward the surface of the outer tube (3) under the influence of centrifugal force. After blood cells and plasma are roughly separated in this way, the plasma separated by the separation membrane (2) is collected in the inner cylinder (1).

The plasma in II (1) is taken out through the pipe ω as appropriate. Blood with a high concentration of blood cells separated from plasma is piped (9)
taken out through.

The pressure difference between the inner tube (1) and the outer tube (3) that sandwich the separation membrane (2) may be the positive pressure applied to the outer tube (33 side) or the positive pressure applied to the inner tube (1) side. From the viewpoint of preventing hemolysis of the outer cylinder (3), it is preferable to apply positive pressure to the outer cylinder (3) side.
To apply positive pressure to the side, for example, the pipe 01) may be closed and blood may be supplied.

Blood processing in the device may be carried out by introducing a fixed amount of blood at once, completely separating the fixed amount of blood, and then taking out the separated blood cells and plasma. Perform the separation operation while introducing the plasma continuously or intermittently, and take out the separated plasma as appropriate.
The separation operation may be stopped and the blood cells may be removed at the stage where M blood cells accumulate between the membrane (a) and the outer cylinder (3) to the extent that the separation efficiency is reduced.

In the present invention, by rotating the outer cylinder (3) as described above, centrifugal force is applied to the blood cells to roughly separate the blood cells and plasma, reducing the blood cell concentration on the surface of the membrane (2). , the pores of the separation 111(2) are prevented from being blocked;
Separation ability does not decrease.

In addition, since the membrane I11 (2 is fixed or the outer cylinder rotates, a relative shear force is also generated in the blood reservoir on the surface of the separation membrane (2). However, the thickness of the shear force is different from that of the conventional method described above. Since it is not as large as in the example, problems such as hemolysis do not occur.

Inside again! ! (11) is fixed, and blood can be taken in and out and plasma can be taken out on the side of the fixed inner cylinder (1), so there is no need for a seal on the rotating shaft. are not in contact with each other through a bearing, etc., and are separated fl
Since they are in contact only through u(2), there is no need for a seal on the rotating shaft.

In the present invention, the gap between the membrane (2) and the outer cylinder (3) is preferably one or more, particularly two or more. If the gap is less than 1 cm, separation of blood cells and plasma by centrifugal force will not be sufficient, and processing capacity will also decrease. The upper limit of the gap is not so limited, but is preferably 30 shoes,
Out of all of them, it's about 15 ugliest.

The rotational speed of the outer cylinder (3) is preferably about 500 to 3600r111n. If the rotation speed is less than 500 rpm, separation will not be sufficient, while if it is greater than 36 GO rpm, hemolysis due to turbulence will likely occur.

The diameter of the outer cylinder (3) is usually about 30 to 100 am.

Separation membranes (a) can be used without any particular restrictions as long as they have a pore size of about 0.2 to 2. Examples of the materials include cellulose triacetate, cellulose diacetate, polyvinyl alcohol, polymethyl methacrylate, polyethylene, and polypropylene. , polysulfone, polymer alloys, etc.

In the present invention, since the inner cylinder (1) is fixed without rotating, the peripheral wall (1a) of the inner cylinder (1) to which the separation wA (2J is attached) efficiently collects the plasma that has passed through the separation membrane ('2J). There are no particular restrictions on its structure as long as it can lead into the interior.For example, a structure in which the peripheral wall (1a) is made up of a continuous wall with many pores, Examples include structures in which multiple vertical and/or horizontal grooves, diagonal or spiral grooves are formed on the outer surface of the wall, and holes communicating with the interior are bored at appropriate locations in the grooves. Also, the surrounding wall (1a) is made of continuous porous resin material, ceramic material, etc. whose pores are larger than those of the separation membrane.
may be configured. More laps! (1a) does not need to be a continuous wall, and may be made of a wire mesh material, for example, or the periphery of the earthen wall (1b) of the cylinder (1) and the bottom wall (1
It is also possible to use a configuration in which the peripheral edge of d) is connected with a large number of rods, a lattice structure, etc.

Further, the driving means for rotating the outer cylinder (3) is not limited to magnetic force, and the rotational force of an electric motor or the like may be mechanically transmitted to the outer cylinder (3).

Although the present invention has been described above with respect to a batch-type separation device, the present invention is not limited to such an example. Take out 31! It is also possible to implement it by a continuation law.

[Effects of the invention] By fixing the separation membrane and rotating the outer cylinder, blood cells are moved outward by the action of centrifugal force, so blood cells do not accumulate on the surface of the separation membrane and separation efficiency does not decrease. .

Further, the configuration in which the separation membrane is fixed and the outer cylinder is rotated has the advantage that the structure of the rotating part is simplified and a seal on the rotating shaft is not required.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view showing one embodiment of the device of the present invention. (Main symbols in the drawing) (1): Fixed inward direction (21 bisected 11 membranes (3) 2 rotating outer cylinder (4): Outer casing

Claims (1)

[Scope of Claims] 1. An outer cylinder rotatable coaxially with the central axis of the inner cylinder is disposed on the outer periphery of a cylindrical fixed inner cylinder having a plasma separation membrane on the peripheral wall surface, and the separation membrane and the outer cylinder are disposed on the outer periphery of the fixed inner cylinder. A plasma separation method comprising supplying blood to a gap and rotating the outer cylinder at high speed to collect plasma into the inner cylinder through the separation membrane. 2. The plasma separation method according to claim 1, wherein the gap between the separation membrane and the outer cylinder is 2 to 15 mm. 3. A cylindrical fixed inner cylinder having a plasma separation membrane on the peripheral wall surface, a rotating outer cylinder rotatably disposed on the outer periphery of the inner cylinder coaxially with the central axis of the inner cylinder, and the rotating outer cylinder. an outer casing that rotatably supports the outer casing, a means for supplying blood to the gap between the separation membrane and the outer cylinder and taking out the blood from which the plasma has been separated, and a means for taking out the separated plasma from the fixed inner cylinder. and a driving means for rotating the rotating outer cylinder at high speed. 4. The device according to claim 3, wherein the gap between the separation membrane and the outer cylinder is 2 to 15 mm. 5. Claim 3, wherein the blood supply and extraction means comprises a pipe that passes through the inner cylinder along the central axis of the inner cylinder and opens between the bottom wall of the inner cylinder and the bottom wall of the outer cylinder. Apparatus described in section.