JP2001050952A - Plasma separation collection method and tool thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To rapidly and easily obtain a method and tool for separating and collecting plasma from a whole blood specimen in a blood inspection at a medical field where occasional and instant properties are required as in an emergency inspection and an in-home inspection. SOLUTION: The method is provided with a process for passing a whole blood specimen through a globule separation filter for separating plasma from the whole blood specimen, and a process for collecting the plasma from the globule separation filter to a capillary. In the tool, a globule separation filter 2 is installed in a tool body 1 with a supply port 1a of the whole blood specimen at an upper portion and at the same time, a collection port 1b of plasma at a lower portion, and a capillary 3 is installed at a collection port 1b of the tool body 1, so that it is located at the lower portion of the globule separation filter 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for separating and recovering plasma for obtaining blood plasma by removing blood cells from a whole blood sample at the time of a blood test in the field of clinical diagnosis, and to a device therefor.

[0002]

2. Description of the Related Art A blood test in the field of clinical diagnosis is performed by collecting blood from a subject and analyzing components in the blood.
Inspect the subject's health, illness, recovery status, etc. In this blood test, blood components are analyzed by a chemical, biochemical or electrochemical method, and many items to be measured are measured from serum or plasma obtained by removing blood cells from whole blood.

[0003] The measurement technology in this blood test has made remarkable progress, and it has become possible to perform a component test even on a sample having a low concentration, so that even if the blood sample is diluted, it is possible to analyze the blood component. ing. Therefore,
If a certain amount of plasma can be collected even if the blood sample is very small, it can be diluted to an arbitrary concentration, and the dilution increases the sample volume, so that multiple items of blood components can be measured simultaneously. .

Conventionally, there has been a centrifugal separation method or a method using a blood cell separation filter for removing blood cells for analyzing components in serum or plasma. In the centrifugation method, a whole blood sample is put into a test tube or the like, and blood cells are precipitated by centrifugation, thereby obtaining plasma without blood cells in the supernatant. In the method using a blood cell separation filter, pressurization from the sample side,
Alternatively, the plasma was collected by the pressure from the collection side.

[0005]

However, the conventional centrifugation method has a problem that if the sample volume is small, the separated blood cells and plasma are resuspended, so that it is difficult to collect only the plasma. Was. Therefore, the centrifugal separation method requires a sample volume of several hundred μl to several ml, and has a problem that a burden on a subject is large because blood collection requires collection with a syringe. Furthermore, the centrifugal separation method requires a special device for centrifugation, and can be processed only in batches, which is disadvantageous in terms of cost for processing a small number of samples, and unsuitable for occasional and immediate processing. There was a problem that there is.

In addition, the above-described method using a blood cell separation filter has a problem that a special device or equipment is required for pressurizing or reducing pressure for recovering plasma, and the operation becomes complicated. Was.

Accordingly, the present invention solves the above-mentioned conventional problems, and provides a quick and easy whole blood sample in a blood test at a medical site where urgency and home examinations are required at any time. The present invention has been made for the purpose of providing a method and apparatus for separating and recovering plasma from blood.

[0008]

Therefore, a method for separating and recovering plasma according to the present invention comprises the steps of passing a whole blood sample through a blood cell separation filter to separate plasma from the whole blood sample, and collecting the plasma from the blood cell separation filter into a capillary tube. It is provided with the step of performing.

According to the plasma separation / collection device of the present invention, a blood cell separation filter is installed in a device main body having a supply port for whole blood samples at the top and a plasma collection port at the bottom, and a blood cell separation filter is provided below the blood cell separation filter. A capillary tube is provided at the collection port of the instrument body so as to be positioned.

In the method for separating and recovering plasma of the present invention and the apparatus therefor, the blood cell separation filter is an asymmetric membrane having an inclined pore diameter, and the membrane has an average pore diameter of 10 μm on the whole blood sample supply side. It is preferable that the average pore diameter on the plasma separation and recovery side is 1 to 3 μm.

Further, in the method for separating and recovering plasma according to the present invention, the volume of the whole blood sample is preferably 10 μl to 1.0 ml.

Further, in the plasma separation and recovery device of the present invention, the upper end of the capillary tube may be brought into contact with the lower center of the blood cell separation filter, or a plasma reservoir may be provided between the blood cell separation filter and the capillary tube.

[0013]

Embodiments of the present invention will be described below in detail with reference to the drawings.

First, as shown in FIG. 1 and FIG. 2, a plasma separation / collection device according to the present invention has a supply port 1a for a whole blood sample at an upper portion thereof.
And a device main body 1 having a plasma collection port 1b at the bottom and a housing space 1c inside. Then, the blood cell separation filter 2 is installed in the accommodation space 1c of the instrument body 1, and the collection port 1b of the instrument body 1 is located below the blood cell separation filter 2.
Is provided with a capillary tube 3. In FIG. 1, the upper end of the capillary tube 3 is brought into contact with the lower center of the blood cell separation filter 2, and in the one shown in FIG. 2, the upper end of the capillary tube 3 is brought into contact with the blood cell separation filter 2. Instead, the plasma reservoir 4 is provided between the blood cell separation filter 2 and the capillary tube 3.

The device main body 1 is made of a synthetic resin material or the like so as not to penetrate a whole blood sample, and its shape and size are not particularly limited as long as the blood cell separation filter 2 can be accommodated therein. Further, the supply port 1a of the instrument body 1 preferably has a diameter of 1.8 mm to 9.8 mm, more preferably 2.8 mm to 6.8 mm. If the diameter is smaller than 1.8 mm, it becomes difficult to supply the whole blood sample, and if the diameter is larger than 9.8 mm, the whole blood sample cannot be supplied uniformly. The diameter of the collection port 1b of the instrument body 1 is based on the outer diameter of the capillary tube 3.

The blood cell separation filter 2 is a porous filter having a function of capturing blood cells without lysing blood cells. For example, the blood cell separation filter 2 is an asymmetric membrane having a slant pore diameter mainly composed of polysulfone or polyethersulfone. The average pore size on the whole blood sample supply side of the membrane is 10 to 50 μm
m, the average pore diameter on the plasma separation and collection side can be 1 to 3 μm. In addition, this blood cell separation filter 2
A membrane that captures blood cells by electrostatic action, such as glass fiber filter paper, or a membrane that contains a polycation and has the added function of condensing and efficiently filtering blood cells, etc. it can. Further, as the blood cell separation filter 2, these membranes can be used alone or a combination of a plurality of these membranes can be used. The shape of the blood cell separation filter 2 is usually a disk shape. When the blood cell separation filter 2 is a disk shape, the diameter is preferably 2.0 mm to 10.0 mm, and the diameter is preferably 3.0 mm to 7.0 mm. More preferably, If the diameter is smaller than 2.0 mm,
Whole blood specimens are less likely to pass through the filter and have a diameter of 10.
If it is larger than 0 mm, the amount of the whole blood sample required for separation and recovery increases accordingly.

The capillary tube 3 can be made of an inorganic material such as quartz or glass, or made of an organic material such as nylon, polyvinyl chloride, or polyethylene, and preferably has a diameter of 0.5 mm to 3.0 mm. More preferably, the diameter is 1.0 mm to 2.0 mm. When the diameter is smaller than 0.5 mm, the internal volume of the capillary is reduced, and when the diameter is larger than 3.0 mm, the capillary phenomenon is less likely to occur. Further, it is preferable that the length of the capillary tube 3 be about 5.0 mm to 10.0 mm from the viewpoint of easy handling.

The plasma reservoir 4 is a space formed between the blood cell separation filter 2 and the capillary tube 3. The inner diameter of the space is the same as that of the supply port 1a for the whole blood sample, and the depth is 1. The storage efficiency is preferably 0 mm to 2.0 mm because of good storage efficiency.

Further, the method for separating and recovering plasma of the present invention
The method includes a step of passing a whole blood sample through a blood cell separation filter to separate plasma from the whole blood sample, and a step of collecting the plasma from the blood cell separation filter into a capillary tube. That is, the method for separating and collecting plasma according to the present invention is performed as follows when the above-described instrument for separating and collecting plasma is used.

First, a step of passing a whole blood sample through a blood cell separation filter to separate plasma from the whole blood sample is performed by supplying whole blood collected from a subject to a blood cell separation filter 2 through a supply port 1a of a plasma separation and collection instrument. Passing the specimen separates the plasma from the whole blood specimen. When this plasma separation and collection device is used, a whole blood sample of 10 μl to 100 μl is sufficient, but it is preferably 10 μl to 1.0 ml.

Next, in the step of collecting plasma from the blood cell separation filter into a capillary, the plasma separated by the blood cell separation filter 2 is collected in the capillary 3 installed in the collection port 1b of the instrument body 1 of the plasma separation and collection instrument. To do. In other words, utilizing the capillary action of the capillary tube 3, the plasma separated by the blood cell separation filter 2 is directly collected from the lower center of the blood cell separation filter 2 in FIG. In what is shown in
The plasma separated by the blood cell separation filter 2 is stored in a plasma reservoir 4 below the blood cell separation filter 2, and the collected plasma is collected. In the filter shown in FIG. 1, the plasma moves only in the portion of the blood cell separation filter 2 that is in contact with the capillary tube 3, but in the filter shown in FIG. 2, the plasma falls from the entire lower surface of the blood cell separation filter 2. It collects in the plasma reservoir 4. Therefore, the one shown in FIG. 2 can more efficiently separate the plasma than the one shown in FIG. 1, and the separation time is shortened.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to embodiments. (Example) In order to carry out the plasma separation and recovery method of the present invention, a whole blood sample was mixed with a blue dye, and a dye-containing whole blood sample 3 was prepared.
0 μl, 50 μl and 100 μl were prepared for each of 10 samples,
These samples were spotted on the upper surface side of the blood cell separation filter 2 of each plasma separation and collection device shown in FIG. 2, and the plasma obtained on the lower surface side was collected in the capillary 3.

The blood cell separation filter 2 in the apparatus for separating and recovering plasma uses a US filter having a diameter of 7.0 mm,
The supply port 1a has a diameter of 4.0 mm, and the capillary 3 has a diameter of 1.0 mm and a length of 5.0 mm.

Each of the collected plasmas was added to 500 μl of physiological saline, and the volume of the plasma collected in the capillary 3 was measured from the absorbance of the dye, and the CV value (coefficient of variation) was determined in order to examine the reproducibility of the volume of the collected plasma. ) Was determined by the following equation 1. The measurement results are shown in Table 1.

[0025]

(Equation 1)

[0026]

[Table 1]

From the measurement results shown in Table 1, the CV value of the apparatus for separating and recovering plasma of the present invention was determined.
l is 3.08%, 50 l is 3.95%,
At the time of 100 μl, it was 3.37%. (Comparative Example) Next, the correlation between the respective blood sugar levels in the plasma separated and recovered by the method of the present invention and the conventional centrifugation method was examined.

First, in the centrifugation method, 5 ml of a whole blood sample is collected from a subject by injection blood sampling, the sample is transferred to a centrifuge test tube, and a hemagglutination inhibitor EDTA is added.
The mixture was centrifuged at 3,000 rpm for 5 minutes using a centrifuge, and the plasma as a supernatant was separated and collected.

According to the method of the present invention, 30 μl of a whole blood sample of the same subject as in the centrifugal separation method is spotted on the upper surface of the blood cell separation filter 2 of the same plasma separation and collection instrument as in the above embodiment, and is obtained on the lower surface. The obtained plasma was collected in the capillary 3.

The plasma separated and recovered by the centrifugal separation method and the method of the present invention were each diluted 10-fold with physiological saline, and the blood glucose level in the plasma was measured. The measurement results are shown in FIG.

As shown in FIG. 3, the correlation between the blood glucose levels in the plasma separated and collected by the method of the present invention and the conventional centrifugal separation method is the measured value of the blood glucose by the centrifugal separation method of 76 to 248 mg / dl. Between the two was good.

[0032]

Since the present invention is constructed as described above, it does not require a conventional centrifugal separator or a special device or equipment for pressurization and depressurization. In addition, it is possible to rapidly and arbitrarily separate and collect a certain amount of plasma from a small amount and an undefined volume of a whole blood sample.

Further, according to the present invention, plasma can be separated and collected from a small amount of a whole blood sample, so that it is only necessary to collect blood with a needle at a fingertip of a subject without using injection for sample collection. Thus, the burden on the subject can be reduced, and the subject can collect blood.

Further, according to the present invention, a blood test can be immediately performed at any time, which is also effective in an emergency test or a home test.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing one embodiment of a plasma separation / collection device of the present invention.

FIG. 2 is a cross-sectional view showing another embodiment of the plasma separation / collection device of the present invention.

FIG. 3 is a diagram showing a correlation between respective blood sugar levels in plasma separated and collected by the method of the present invention and a conventional centrifugation method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Instrument main body 1a Supply port 1b Collection port 2 Blood cell separation filter 3 Capillary tube 4 Plasma reservoir

Claims (6)

[Claims] 1. A method for separating and recovering plasma comprising the steps of: passing a whole blood sample through a blood cell separation filter, separating plasma from the whole blood sample; and collecting the plasma from the blood cell separation filter into a capillary tube. 2. A blood cell separation filter is provided in a device body having a whole blood sample supply port at an upper portion and a plasma collection port at a lower portion, and the device is positioned below the blood cell separation filter. A plasma separation and collection instrument, wherein a capillary tube is provided at a collection port of the main body. 3. The blood cell separation filter is an asymmetric membrane having an inclined pore diameter, and the membrane has an average pore diameter of 10 to 50 μm on the whole blood sample supply side and an average pore diameter of 1 to 3 μm on the plasma separation and collection side. 3. The method for separating and recovering plasma according to claim 1 or 2, and an instrument therefor. 4. The volume of a whole blood sample is 10 μl to 1.0 ml.
The method for separating and recovering plasma according to claim 1, wherein: 5. The plasma separation and collection device according to claim 2, wherein an upper end of the capillary tube is brought into contact with a lower center of the blood cell separation filter. 6. The plasma separation and collection device according to claim 2, wherein a plasma reservoir is provided between the blood cell separation filter and the capillary.