CN217489389U

CN217489389U - Blood separating device

Info

Publication number: CN217489389U
Application number: CN202122831162.8U
Authority: CN
Inventors: 秦大东
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-11-18
Filing date: 2021-11-18
Publication date: 2022-09-27
Anticipated expiration: 2031-11-18

Abstract

The utility model discloses a blood separating device, relating to the field of blood separation, which comprises a centrifugal device and a separating tube, wherein the separating tube does circular motion by taking the rotation center of the centrifugal device as the center when in use; the separation tube comprises a blood inlet, a plasma outlet, a red blood cell outlet and a nucleated cell outlet, wherein the plasma outlet is positioned at one end close to the rotation center, and the red blood cell outlet and the nucleated cell outlet are positioned at one end far away from the rotation center; the blood inlet is continuously filled with blood after the separation tube is moved, during which time the blood plasma, red blood cells and nucleated cells in the separation tube continuously or intermittently flow out when the separation threshold is reached. Compared with the prior art, this application adopts and guarantees the centrifugal settlement distance, lasts each component in the centrifugal method separation blood, makes the separation effect obviously promote, and the actual effect is very showing.

Description

Blood separating device

Technical Field

The utility model relates to a medical instrument, in particular to a blood separating device.

Background

The mixture formed by collecting blood from a human body into a blood collection bag is called whole blood, i.e. all components including blood cells and plasma. There are many disadvantages to whole blood transfusion, and modern blood transfusion advocates no or little use of whole blood, while some nucleated cells in whole blood can be treated by cell transplantation, thus requiring separation of whole blood. The main components in whole blood are:

relative cell density

Erythrocyte 1.09-1.11

Acidophilic acid 1.09-1.095

Neutral 1.080-1.085

Lymphocytes 1.062-1.077

Monocyte 1.050-1.066

Natural killer cell 1.050-1.070

Platelets 1.030-1.060

Blood plasma 1.025-1.030

Eosinophils, basophils, lymphocytes, monocytes and natural killer cells belong to white blood cells and are nucleated cells, and the white blood cells are called white blood cells together, and because red blood cells do not have nuclei, all the white blood cells can be called nucleated cells.

As can be seen from the above, since there are differences in relative densities of plasma, erythrocytes and nucleated cells, the main method for separating whole blood in the prior art is centrifugation, which is based on the principle that after whole blood is centrifuged by a centrifuge, the components of whole blood are separated into a plasma layer and an erythrocyte layer in a blood bag due to the difference in specific gravity, and the separated whole blood is transferred into the plasma bag by an extrusion or siphon method, and then SAGM (maintenance fluid) is added into the mother bag of the remaining erythrocytes after plasma separation, and after the blood bag tube is heat-sealed and broken, the whole blood is successfully separated into plasma and an erythrocyte suspension.

The umbilical cord blood is the blood remained in the placenta and the umbilical cord after the delivery of the fetus, the ligation and the separation of the umbilical cord, contains hematopoietic stem cells which can reconstruct the hematopoietic and immune systems of a human body, can be used for hematopoietic stem cell transplantation, and can treat more than 80 diseases. Cord blood therefore becomes an important source of hematopoietic stem cells, particularly of non-hematopoietic relationship. Is also a very important human biological resource. The main cost of the umbilical cord blood is red blood cells, nucleated cells (hematopoietic stem cells belong to one kind of the nucleated cells) and blood plasma, the volume of the hematopoietic stem cells in the umbilical cord blood accounts for less than 1 percent of the total volume of the umbilical cord blood, meanwhile, the hematopoietic stem cells need to be stored in liquid nitrogen, the storage cost is very high after long-time liquid nitrogen storage, and partial blood plasma and red blood cells in the umbilical cord blood need to be removed and then frozen for storage in order to improve the storage capacity.

There are three common methods for separating nucleated cells, namely triple blood bag + centrifuge, AXP automated preparation system and SEPAX preparation system, but the above separation methods still have several drawbacks. The first is as follows: the plasma separated has varying degrees of residual red blood cells and excess plasma remaining in the red blood cells due to differences in centrifuge quality and operator proficiency. The second is as follows: because the specific gravity of the nucleated cells is similar to that of the red blood cells, the red blood cells and the nucleated cells cannot be effectively separated, so that the separation rate of the nucleated cells is low, and a large number of nucleated cells remain in the red blood cells. The third is: in order to ensure that stem cells are not excessively lost, less red removal is selected, and the final concentration volume is more selected from 20-30 ml. The excess volume of concentrate means more cryoprotectant is needed and takes up more space.

SUMMERY OF THE UTILITY MODEL

The utility model provides a blood separating method and a separating device aiming at the defects in the prior art, the application adopts a continuous centrifugal continuous collection method to ensure the stability of blood layering in the centrifugal device, and solves the problems that part of nucleated cells are mixed in the red blood cells and the collection rate is low when the nucleated cells are collected by a gravity separation method of the red blood cells and the nucleated cells; the device and the method have the advantages that the collection rate of the nucleated cells reaches over 90 percent, theoretically 99 percent, so that the concentrated volume of the nucleated cells is greatly reduced to 5ml to 10ml, the storage cost is obviously reduced, and the actual use effect is excellent.

In order to solve the technical problem, the utility model discloses a following technical scheme can solve: a blood separation method, need to use the blood separation facility, the blood separation facility includes centrifugal device and separation tube, the separation tube does the circular motion with the centre of rotation of the centrifugal device as the centre when using; the separation tube comprises a blood inlet, a plasma outlet, a red blood cell outlet and a nucleated cell outlet, wherein the plasma outlet is positioned at one end close to the rotation center, and the red blood cell outlet and the nucleated cell outlet are positioned at one end far away from the rotation center; the blood inlet is continuously filled with blood after the separation tube is moved, during which time the blood plasma, red blood cells and nucleated cells in the separation tube continuously or intermittently flow out when the separation threshold is reached.

Preferably, sensors are arranged on two sides of the nucleated cell outlet, and the sensors determine the separation threshold of the red blood cells and the nucleated cells.

A blood separating device comprising a centrifuge and a separating tube, the separating tube comprising a blood inlet, a plasma outlet, a red blood cell outlet, and a nucleated cell outlet, the plasma outlet being located at an end near the center of rotation, the red blood cell outlet and the nucleated cell outlet being located at an end away from the center of rotation; the separating tube is obliquely arranged, one end with the red blood cell outlet and the nucleated cell outlet is higher than one end with the plasma outlet, the nucleated cell outlet is higher than the red blood cell outlet, and the two sides of the nucleated cell outlet are provided with sensors.

Preferably, the sensor is a light sensor.

Preferably, flow valves are disposed on the blood inlet, the plasma outlet, the nucleated cell outlet, and the red blood cell outlet.

Preferably, the flow valve is an adjustable peristaltic pump.

The other blood separation device comprises a centrifugal device and a separation tube, wherein the separation tube comprises a straight tube section close to a rotation center and a bent tube section far away from the rotation center, the bent tube section is bent upwards, a blood inlet and a plasma outlet which is closer to the rotation center than the blood inlet are formed in the straight tube section, a nucleated cell outlet and a red blood cell outlet which is farther away from the rotation center than the nucleated cell outlet are formed in the bent tube section, and sensors are arranged on two sides of the nucleated cell outlet.

Preferably, the straight pipe section is horizontally arranged.

Preferably, the elbow section is bent in a 90-degree arc, and the straight pipe section is positioned in the tangential direction of the elbow section.

Preferably, the sensor is a light sensor.

Preferably, the flow valve is an adjustable peristaltic pump.

Preferably, the plasma outlet is located at a side end of the straight tube section close to the rotation center, the red blood cell outlet is located at a side end of the bent tube section away from the rotation center, the nucleated cell outlet is located at an upper portion of the bent tube section, and the blood inlet is located at an upper portion of the straight tube section.

Preferably, the blood inlet is higher than the plasma outlet, and the nucleated cell outlet and the red blood cell outlet are higher than the plasma outlet.

When centrifuged in a cell suspension liquid, the sedimentation rate of the cells is proportional to the centrifugal force. The physical properties of the solution also affect the rate of sedimentation. At a fixed centrifugal force and liquid viscosity, the settling rate and particle size are proportional to the difference between its own density and the density of the surrounding medium. The sedimentation equation for a sphere in a centrifugation range is: v = d ² （ρ-ρ ₀ ) g/θ η, where V is sedimentation velocity, d is cell diameter, ρ is cell density, ρ ₀ Is the density of the medium, g is the centrifugal force, theta is the friction coefficient ratio of the cells to the standard particles of equal volume, and eta is the absolute viscosity of the medium.

From the above formula, the density of blood cells is higher than that of plasma, and during the centrifugation of blood, red blood cells and nucleated cells move to the bottom. However, there is a tendency that nucleated cells are concentrated toward the upper layer because the nucleated cells have a small diameter and density and a small sedimentation velocity, while the red blood cells have a large diameter and density and a sedimentation velocity greater than that of the nucleated cells. The red blood cells rapidly settle and cause the surrounding liquid to move upwards, driving the white blood cells to move upwards. The speed of the red blood cells is reduced, and the red blood cells are reduced more quickly, so that the surrounding liquid is moved upwards more favorably. Cell concentration-volume ratio of cells to total fluid, the greater the cell concentration, the closer the red blood cells are to the white blood cells, and the more favorable the convection. The longer the settling distance, the more fully the convection effect.

However, the following problems are present in the case of disposable blood separation: 1. in order to accelerate the descending speed of the red blood cells, only the centrifugal force can be increased, the requirement on a centrifugal machine and separation equipment is high, and the cost is greatly increased. 2. Cell concentration is an inherent property of blood and cannot be changed. 3. The sedimentation distance is different from the bottom at different positions, the sedimentation distance is different and cannot be changed, and after the blood is added into the centrifugal bag/tube, the cell separation effect at the upper part is good and the cell separation effect at the lower part is not good. The existing disposable blood separation equipment can only increase the efficiency in the direction of larger centrifugal power and larger separator volume.

The application changes disposable blood separation into continuous blood separation, completely overcomes the problems, and simply adopts different separation principles to avoid the problems. The basic idea of the present application may be understood as "continuous infusion, intermittent outflow". If continuous infusion of blood is required after filling of the separation tube or after blood stratification, the stratified plasma, erythrocytes, nucleated cells must be shed, which in the present case are not shed simultaneously, but only after reaching a predetermined threshold. Generally, when the plasma triggers the threshold after the separation tube is filled or the blood is stratified, the plasma is discharged, and if the plasma is discharged, the volumes of the erythrocytes and the nucleated cells in the separation tube become larger and larger, and if the volumes of the erythrocytes and the nucleated cells trigger the threshold, the erythrocytes and the nucleated cells are also discharged. Under the continuous or intermittent outflow of plasma, red blood cells and nucleated cells, the volume of the red blood cells and the nucleated cells in the separation tube is always in the optimal absorption volume. Because of the shape and the placing angle of the separation tube in the application, the separation of the red blood cells and the nucleated cells is quite thorough, and the red blood cells and the nucleated cells are basically not mixed. As long as blood is not exhausted, plasma, nucleated cells and erythrocytes are orderly sucked under the monitoring of the light sensor and the dynamic regulation of the flow valve, the layering of the plasma, the nucleated cells and the erythrocytes in the separation tube is stable all the time, and the purity of the collected plasma, the collected erythrocytes and the nucleated cells can be ensured. The collection rate of collection mode in this application with nucleated cell has improved more than 90% ~95%, if the separator tube is small enough, can reach 99% in theory, and far surpass the collection rate in present stage, still greatly reduced the collection volume simultaneously, only need collect 5ml to 10 ml's volume in this application can collect the most of nucleated cell in 200ml, very big reduction the cost when storing nucleated cell.

Drawings

Fig. 1 is a schematic diagram of embodiment 1 of the present invention.

Fig. 2 is a schematic diagram of embodiment 2 of the present invention.

Detailed Description

Example 1: a blood separating device comprises a centrifugal device and a separating tube, wherein a placing table is usually arranged on the centrifugal device, and the placing table and a centrifugal shaft in the centrifugal device move together. The separating tube sets up on placing the platform, and blood bag, plasma bag, collection bag, red blood cell bag also set up on placing the platform simultaneously. The volume of the separation tube is smaller than the volume of the blood to be centrifuged, the volume of the separation tube is usually between 10ml and 20ml, and the separation tube is a straight tube. And if necessary, the volume of the separation tube can be increased or reduced, basically, the volume of the separation tube is one tenth to one fifth of the blood to be separated, and in fact, the collection effect is better when the volume of the separation tube is more than one tenth of the blood to be separated, but the total separation time is longer. In this application the centrifugal shaft can be regarded as the centre of rotation in the centrifugal movement.

The separating tube comprises a blood inlet 1, a plasma outlet 2, a red blood cell outlet 3 and a nucleated cell outlet 4, wherein flow valves are arranged on the blood inlet 1, the plasma outlet 2, the nucleated cell outlet 4 and the red blood cell outlet 3, and the flow valves are adjustable peristaltic pumps. The separation tube is arranged obliquely at an angle of between 0 ° and 60 °, preferably between 15 ° and 45 °. The plasma outlet 2 is positioned at one end close to the rotation center, and the red blood cell outlet 3 and the nucleated cell outlet 4 are positioned at one end far away from the rotation center; the nucleated cell outlet 4 is higher than the red blood cell outlet 3. The end having the red blood cell outlet 3 and the nucleated cell outlet 4 is higher than the end having the plasma outlet 2, and the blood inlet 1 is located near the end located near the center of rotation and between the plasma outlet 2 and the nucleated cell outlet 4. Meanwhile, the position of the nucleated cell outlet 4 needs to be accurately designed, and the position of the nucleated cell outlet 4 needs to be determined according to the volume ratio of nucleated cells in blood, so that the nucleated cell aggregation region is positioned at the nucleated cell outlet 4 after the blood is separated.

Inductors 5 are arranged on the upper side and the lower side of the nucleated cell outlet 4, and the inductors 5 are light inductors. The position of the light sensor also needs to be precisely designed according to the volume ratio of nucleated cells in blood, usually the light sensor is positioned at the separation position of the nucleated cells and the red blood cells, usually the light sensor is positioned below the outlet 4 of the nucleated cells, and another light sensor positioned above the outlet 4 of the nucleated cells mainly detects the thickness of the nucleated cell layer.

The separation principle when the inclined angle of the separation tube is 15 degrees is as follows: blood enters from the blood inlet, the gravity and the centrifugal force form resultant force, blood cells move along the direction of the resultant force under the action of the resultant force, namely, the blood cells move towards the bottom of the separation tube, and the red blood cells are faster and the white blood cells are slower. When the red blood cells contact the lower part of the separating tube, the red blood cells have high speed and high inertia, and then the red blood cells can rush to the lower wall of the separating tube, and the white blood cells are on the upper layer of the red blood cells. Because red blood cells are denser than white blood cells, they remain at the bottom of the separation tube during the movement from just contacting the bottom of the tube to the outlet under the combined force. At this point the blood in the separation tube separates but does not fill. When the light sensor below the outlet of the nucleated cells detects the red blood cells, the valve of the outlet of the red blood cells is opened, and the accumulation volume of the red blood cells is maintained and kept unchanged. The volume of the red blood cells is kept stable, the thickness of the white blood cells is gradually accumulated and thickened, and when the white blood cells are detected by the light sensor on the upper side of the nucleated cell outlet, the nucleated cell outlet is opened and the thickness of the nucleated cells is kept unchanged. When no blood flows into the blood inlet, the erythrocyte layer and the leukocyte layer on the lower side of the separation tube are gradually shortened under the action of centrifugal force and are deposited downwards until all erythrocytes flow out of the outlet. After all leukocytes flow out from the nucleated cell outlet, the plasma flow was continued until the desired volume was collected. The separation is complete. In the separation process, the separation tube is not full all the time.

The method for separating nucleated cells using the blood separating apparatus of example 1, in which the nucleated cells to be collected were stem cells in the cord blood. The amount of umbilical cord blood is more than 100 ml. The method comprises the following steps of A: the blood inlet is connected with the blood bag, the plasma outlet is connected with the plasma bag, the nucleated cell outlet is connected with the collection bag, the red blood cell outlet is connected with the red blood cell bag, then the blood inlet is opened to allow the blood to flow into the separation tube, and the amount of the blood flowing into the separation tube is one half to two thirds of the capacity of the separation tube. And B: rotating the centrifugal device to make the separation tube rotate around the rotation center, at this time, the blood in the separation tube is layered, the blood flows into the blood after layering, and the plasma outlet is opened to make the plasma continuously flow into the plasma bag. Step C: after the light sensor for sensing the red blood cells senses the red blood cells, the red blood cell outlet is opened, the red blood cells flow into the red blood cell bag, and after the light sensor for sensing the red blood cells does not sense the red blood cells, the red blood cell outlet is closed, so that the red blood cells in the separation tube are always kept in stable layered positions. Step D: when the light sensor sensing the thickness of the nucleated cells senses the nucleated cells, the outlet of the nucleated cells is opened to allow the nucleated cells to flow into the collection bag, and when the light sensor does not sense the nucleated cells, the outlet of the nucleated cells is closed. And D, repeating the step C and the step D until the blood is exhausted or the collection bag is full, and continuously flowing the blood into the separation tube in the step C and the step D to ensure that the blood is layered in the separation tube all the time until the blood is exhausted or the collection bag is full. The collection rate of the stem cells collected by the method is more than 95 percent, the collection amount can be as low as 5ml, partial plasma flows into the collection bag only at the end, and the pollution degree of the stem cells is very small.

Example 2: a nucleated cell separation apparatus includes a centrifugal apparatus, and a placing table is usually provided on the centrifugal apparatus, and moves together with a centrifugal shaft in the centrifugal apparatus. The separator tube sets up on placing the platform, and blood bag, plasma bag, collection bag, red blood cell bag also set up on placing the platform simultaneously. The separation tube has a volume less than the volume of the blood to be centrifuged, typically between 10ml and 20ml, and may be larger or smaller if desired. In this application the centrifugal shaft can be regarded as the centre of rotation in the centrifugal movement.

The separation tube comprises a straight tube section close to the centrifugal shaft and a bent tube section far away from the centrifugal shaft, the straight tube section and the bent tube section are integrally same, and smooth transition between the straight tube section and the bent tube section can also be performed at an included angle. The bent pipe section is bent upwards in a curve or in a straight line. The straight pipe section is horizontally arranged or has a certain included angle with the horizontal plane, if the straight pipe section has the included angle with the horizontal plane, the straight pipe section can be preferably inclined upwards, and the highest height does not exceed the lowest height of the bent pipe section. Usually, the elbow section is bent in a 90-degree arc, the straight pipe section is positioned in the tangential direction of the elbow section, and smooth transition is realized between the straight pipe section and the elbow section.

The straight tube section is provided with a blood inlet 1 and a plasma outlet 2 which is closer to the centrifugal shaft than the blood inlet 1, and finally the plasma outlet 2 is arranged on the side wall at the outermost side of the straight tube section. The bend section is provided with a nucleated cell outlet 4 and a red blood cell outlet 3 which is more far away from the centrifugal shaft than the nucleated cell outlet 4, and the red blood cell outlet 3 is preferably arranged on the outermost side wall of the bend section. Meanwhile, the position of the nucleated cell outlet 4 needs to be accurately designed, and the position of the nucleated cell outlet 4 needs to be determined according to the volume ratio of nucleated cells in blood, so that the nucleated cell aggregation region is positioned at the nucleated cell outlet 4 after the blood is separated. The elbow section is provided with two sets of light sensors 51, the nucleated cell outlet 4 is positioned between the light sensors 51, the positions of the light sensors 51 also need to be accurately designed according to the volume ratio of nucleated cells in blood, the light sensors 51 are usually positioned at the separation positions of the nucleated cells, blood plasma and red blood cells, and the further light sensors 51 can be positioned at the positions of the separation positions of the nucleated cells and the blood plasma close to the blood plasma and the separation positions of the nucleated cells and the red blood cells close to the red blood cells. The blood inlet 1, the plasma outlet 2, the nucleated cell outlet 4 and the red blood cell outlet 3 are all provided with flow valves, and the flow valves are adjustable peristaltic pumps.

In this embodiment, the separating device is divided into two parts, namely a straight pipe section and a bent pipe section, which are communicated with each other, the straight pipe section is horizontally placed, the bent pipe section is bent upwards and away from the centrifugal shaft, and certainly, the straight pipe section can also form a certain included angle with the horizontal plane, but the bent pipe section is required to be bent upwards. When blood cells reach the joint of the straight pipe and the bent pipe, red blood cells and nucleated cells with high specific gravity are thrown to the bent pipe section during centrifugation, and the speed of the red blood cells is higher than that of the white blood cells. According to the formula of centrifugal force: f = mV2/r, F-centrifugal force to which the cell is subjected, m-cell mass, V-cell velocity, r-radius of the arc of the bend. The red blood cells have larger mass and higher speed than the white blood cells, all the red blood cells have much larger force than the white blood cells to be attached to the lower part of the elbow, the white blood cells are on the upper layer of the red blood cells, the red blood cells are on the upper part of the elbow, namely the bottom of the whole separation tube, and the nucleated cells are on the lower part of the elbow, namely between the blood plasma and the red blood cells. In order to achieve a better collecting effect, the plasma extends to the bent pipe section, the boundary between the nucleated cells and the red blood cells and the plasma is clear and distinct, the red blood cells move upwards all the time under the combined action of centrifugal force and gravity during rotation, the nucleated cells move downwards all the time at the red blood cell gathering position and move upwards at the plasma gathering position, and meanwhile, the centrifugal sedimentation distance is guaranteed through the design of the bent pipe and the straight pipe, so that part of the nucleated cells and the red blood cells cannot be mixed, most of the nucleated cells are gathered together, and therefore the nucleated cells are better separated, and the collecting difficulty is greatly reduced.

The method for separating nucleated cells using the blood separating apparatus of example 2, in which the nucleated cells to be collected were stem cells within the umbilical cord blood. The amount of umbilical cord blood is 100ml or more. The method comprises the following steps of A: the blood inlet is connected with the blood bag, the plasma outlet is connected with the plasma bag, the nucleated cell outlet is connected with the collection bag, the red blood cell outlet is connected with the red blood cell bag, and then the blood inlet is opened to allow the blood to flow into the separation tube. And B, step B: rotating centrifugal device, letting the separator tube rotatory with the rotation center, nucleated cell and erythrocyte move to the bend section this moment, and plasma moves to the straight tube section, and the blood layering in the separator tube after the separator tube is full, and plasma is located the straight tube section and extends to the bend section, and the erythrocyte is located the bend section bottom, and nucleated cell is located between plasma and the erythrocyte, and the photo sensors that are located nucleated cell export both sides this moment sense plasma and erythrocyte respectively. And C: the plasma outlet is opened to allow plasma to continue flowing into the plasma bag. Step D: when the light sensor for sensing the red blood cells senses the red blood cells, the red blood cell outlet is opened, the red blood cells flow into the red blood cell bag, and when the light sensor for sensing the red blood cells does not sense the red blood cells, the red blood cell outlet is closed, so that the red blood cells in the separation tube are always stably kept at the initial layering position. Step E: when the light sensor for sensing the blood plasma does not sense the blood plasma, the nucleated cell outlet is opened to allow the nucleated cells to flow into the collection bag, and when the light sensor for sensing the blood plasma senses the blood plasma, the nucleated cell outlet is closed. Repeating steps C, D and E until the blood is exhausted or the collection bag is full, and continuously flowing blood into the separation tube in steps C, D and E to allow the separation tube to be full until the blood is exhausted or the collection bag is full. The collection rate of the stem cells collected by the method is more than 95 percent, the collection amount can be as low as 5ml, partial plasma can flow into the collection bag only at the end, and the pollution degree of the stem cells is very small.

Claims

1. A blood separating device comprising a centrifuge and a separating tube, wherein the separating tube comprises a blood inlet, a plasma outlet, a red blood cell outlet and a nucleated cell outlet, the plasma outlet is located at one end near the center of rotation, and the red blood cell outlet and the nucleated cell outlet are located at one end away from the center of rotation; the separating tube is obliquely arranged, one end with the red blood cell outlet and the nucleated cell outlet is higher than one end with the plasma outlet, the nucleated cell outlet is higher than the red blood cell outlet, and the two sides of the nucleated cell outlet are provided with sensors.

2. A blood separation apparatus according to claim 1 wherein the sensor is a light sensor.

3. A blood separation device according to claim 2 wherein flow valves are provided on the blood inlet, the plasma outlet, the nucleated cell outlet and the red blood cell outlet.

4. The other blood separation device comprises a centrifugal device and a separation tube, and is characterized in that the separation tube comprises a straight tube section close to a rotation center and a bent tube section far away from the rotation center, the bent tube section is bent upwards, a blood inlet and a plasma outlet which is closer to the rotation center than the blood inlet are arranged on the straight tube section, a nucleated cell outlet and a red blood cell outlet which is farther from the rotation center than the nucleated cell outlet are arranged on the bent tube section, and sensors are arranged on two sides of the nucleated cell outlet.

5. A blood separation device according to claim 4 wherein the straight tube section is arranged horizontally.

6. A blood separation device according to claim 5 wherein the elbow section is bent in a 90 ° arc and the straight section is tangential to the elbow section.

7. A blood separation device according to claim 6 wherein the sensor is a light sensor.

8. A blood separation device according to claim 4 wherein flow valves are provided at the blood inlet, the plasma outlet, the nucleated cell outlet and the red blood cell outlet.