JP5490492B2 - Plasma separator and blood analyzer - Google Patents

Description

  The present invention relates to a plasma separator for separating a plasma component from blood and a blood analyzer for analyzing blood by measuring a predetermined component in the plasma component using the plasma separator.

  Conventionally, as a method for separating plasma components from blood, for example, as shown in Patent Document 1, a capillary channel is formed by overlapping two flat plates with a predetermined distance between them, and the capillary channel is formed in the capillary channel. It is considered that a blood cell component and a plasma component are separated from each other by providing an obstruction in the blood vessel.

  However, the idea of separating the blood cell component and the plasma component by providing an obstruction projection in the capillary channel introduces the blood cell component into the capillary channel, and is easily hemolyzed in the capillary channel. The plasma component may not be sufficiently separated. Further, not only the separation performance of the blood cell component and the plasma component is affected by the arrangement of the obstacle protrusion, but also the blood cell clogging in the obstacle protrusion in the capillary channel needs to be considered.

  In addition, as shown in Patent Document 2, it is also considered that a plurality of protrusions are provided on the surface of a substrate and a plasma component is separated from blood using a capillary phenomenon that occurs on a side peripheral surface between the protrusions.

  However, there is a risk of blood flowing along many protrusions, which is a sanitary problem. There is also a problem that plasma flows through a large number of protrusions due to capillary action, and the blood cell component may be hemolyzed, so that the blood cell component and the plasma component cannot be sufficiently separated.

JP 2001-183363 A Special table 2008-547017

  Therefore, the present invention has been made to solve the above-mentioned problems all at once, and suppresses blood cell components from entering the capillary channel and prevents hemolysis of the blood cell components in the capillary channel. At the same time, it is a main intended problem that the plasma component can be easily separated from the blood by easily introducing the plasma component into the capillary channel.

  That is, the plasma separator according to the present invention is a plasma separator that introduces blood into a capillary channel formed therein and separates plasma components from the blood, and has at least an inlet in the capillary channel on the surface. A first substrate having a concavo-convex structure for forming a portion, and a second substrate provided in close contact with the first substrate and forming an inlet portion in the capillary channel between the concavo-convex structure, and Hydrophilic treatment is applied to at least the inner surface of the opening of the concavo-convex structure of the first substrate and the surface of the second substrate facing the concavo-convex structure, and the capillary flow is performed by bringing the first substrate and the second substrate into close contact with each other. In the state where the inlet part in the channel is formed, the shape of the part subjected to the hydrophilic treatment in the cross section of the inlet part of the capillary channel allows the plasma component to pass through capillary action without passing the blood cell component. And characterized in that. The inlet portion in the capillary channel is a portion from the opening of the capillary channel to a predetermined distance.

  In such a case, since the blood cell component does not pass through the shape of the portion subjected to the hydrophilic treatment in the cross section of the inlet portion in the capillary channel, the blood cell component channel at the inlet portion in the capillary channel. Can be prevented, and plasma components can be separated from blood and introduced into the capillary channel. Further, in the structure in which a substantially rectangular wave-shaped uneven structure is formed on the first substrate and the second substrate is brought into close contact with the first substrate to form at least an entrance portion in the capillary channel, at least an opening of the uneven structure of the first substrate is formed. Since the hydrophilicity can be added to the capillary channel only by applying hydrophilic treatment to the inner surface of the part and the surface of the second substrate facing the concavo-convex structure, the structure and production of the plasma separator is simple.

  As the hydrophilic treatment, it is conceivable to irradiate oxygen plasma or ultraviolet rays from the top of the uneven structure of the first substrate. At this time, although depending on the configuration of the concavo-convex structure, the hydrophilic treatment to the inner surface of the opening of the concavo-convex structure is relatively simple, but the hydrophilic treatment to the bottom inner surface of the concavo-convex structure is difficult due to the problem of irradiation conditions, etc. There's a problem. On the other hand, when the entire concavo-convex structure is subjected to a hydrophilic treatment, there is a possibility that the hydrophilicity may be introduced into the flow path even to the blood cell component over the entire inner surface. Considering these, in order to suitably realize the hydrophilic treatment to the uneven structure and prevent the blood cell component from entering the flow path, the inner surface of the opening of the uneven structure is hydrophilic, and the uneven structure It is desirable that the inner surface of the bottom of the substrate is hydrophobic.

  In order to facilitate the introduction of blood into a plurality of capillaries, and to prevent blood cells from being accumulated at the inlet of each capillary channel and hindering the flow of plasma components, the plurality of capillaries It is desirable to have a blood supply unit that communicates, and the surface of the blood supply unit is subjected to a hydrophilic treatment.

  Further, the blood analyzer according to the present invention introduces blood into a plurality of capillary channels formed therein, and separates plasma components from the blood, and plasma separated by the plasma separator A first substrate having a concavo-convex structure with a substantially rectangular wave shape in cross section that forms at least an inlet portion of the capillary channel on a surface thereof, and the measurement substrate that contacts a component; A second substrate that is provided in close contact with the substrate and forms an inlet portion in the capillary channel between the concavo-convex structure and at least an inner surface of the concavo-convex structure of the first substrate and the second substrate. The surface facing the concavo-convex structure is subjected to a hydrophilic treatment, and the first and second substrates are brought into close contact with each other to form an inlet portion in the capillary channel. In the cross section of the entrance portion, the shape of the portion subjected to the hydrophilic treatment is such that the blood cell component does not pass and the plasma component passes by capillary action, and the measurement electrode is the concavo-convex structure of the second substrate. The plasma component is embedded in a surface facing the plasma and separated by the capillary flow path.

  According to the present invention configured as described above, it is possible to prevent blood cell components from entering the capillary channel, thereby preventing hemolysis of the blood cell component in the capillary channel, and plasma components in the capillary channel. The plasma component can be suitably separated from the blood.

1 is a schematic perspective view of a blood analyzer according to an embodiment of the present invention. It is a top view of the plasma separator of the embodiment. It is an AA line sectional view of the plasma separator of the embodiment. It is a BB line expanded sectional view of the plasma separator of the embodiment. It is a schematic diagram of the blood analyzer which concerns on deformation | transformation embodiment. It is sectional drawing of the plasma separator which concerns on deformation | transformation embodiment.

  Hereinafter, an embodiment of a blood analyzer according to the present invention will be described with reference to the drawings.

<Device configuration>
The blood analyzer 100 according to the present embodiment is for separating a plasma component from blood and measuring the concentration of a predetermined component such as uric acid contained in the plasma component. As shown in FIG. A plasma separator 2 that separates plasma components from blood, a measurement electrode 3 for contacting the plasma components separated by the plasma separator 2 and energizing the plasma components, and a voltage applied to the measurement electrode 3 And an information processing device 4 including a CPU, a memory, and the like that calculate a concentration of a predetermined component such as uric acid contained in a plasma component by measuring a current value applied and flowing.

  The plasma component is a component containing water, plasma protein, and the like, and is a component to be separated that is smaller than a predetermined size (2 μm in this embodiment). The blood cell component is a component containing red blood cells, white blood cells, and platelets, and is a non-separation target component larger than the predetermined size (2 μm).

  As shown in FIG. 2, the plasma separator 2 introduces blood into a capillary channel 2L formed therein to separate plasma components from the blood, and blood is supplied by dropping or the like. A capillary flow that is provided in communication with the blood supply unit 2D and separates the blood cell component and the plasma component by introducing the plasma component in the blood supplied to the blood supply unit 2D into the inside by capillary action. 2L. The capillary channel 2L of the present embodiment has a plurality of capillary channels 2L1 having one end communicating with the blood supply unit 2D and substantially linear channels arranged in parallel to each other, and the plurality of capillary channels It consists of a capillary large flow path 2L2 communicating with the other end of 2L1. The other end of the large capillary channel 2L2 is open to the atmosphere. In FIG. 2, the hatched portion indicates the plasma component in the separation process. In addition, finally, plasma components are separated over the entire length of the capillary channel 2L, and a large amount of plasma components can be collected.

  As a specific configuration of the plasma separator 2, as shown in FIGS. 2 to 4, at least the inlet portion of the capillary channel 2L on the surface (in this embodiment, a plurality of capillary small channels 2L1 are capillary channels 2L). The first substrate 21 having a concavo-convex structure 212 having a substantially rectangular wave shape in cross section forming the first substrate 21 and the concavo-convex structure 212 in the capillary channel 2L. And a second substrate 22 that forms an inlet portion (a plurality of capillary small flow paths 2L1).

  The first substrate 21 is made of, for example, PMMA, which is easy to mold and inexpensive, and is a flat plate (for example, 1 cm square) having a substantially rectangular shape as shown in FIG. A concave portion 211 that forms the supply portion 2D, a concavo-convex structure 212 having a substantially rectangular wave shape in cross section that forms the plurality of capillary channels 2L1, and a concave portion 213 that forms the large capillary channel 2L2.

  The recess 211 is formed at one end of the first substrate 21 so that the blood supply unit 2D communicates with all the capillary small channels 2L1, and in the present embodiment, has a substantially rectangular shape in plan view. is there. Further, the depth of the concave portion 211 is the same as a concave groove of the concave-convex structure 212 described later, and the bottom surface of the concave portion 211 and the bottom surface of the concave-convex structure 212 are flush with each other.

  The concavo-convex structure 212 of the present embodiment forms a plurality of capillary small channels 2L1 that are inlet portions in the capillary channel 2L. The concavo-convex structure 212 has a substantially equal cross-sectional shape, and the cross-section has a substantially rectangular wave shape. That is, the concavo-convex structure 212 is configured by arranging a plurality of concave grooves having a substantially U-shaped cross section in parallel. As specific dimensions, the width of the groove is, for example, 2 μm, and the height is, for example, 9 μm.

  Like the first substrate, the second substrate 22 is made of, for example, PMMA, and is a flat plate having a substantially rectangular shape as shown in FIG. 2, covering the concavo-convex structure 212 formed on the surface of the first substrate 21, The capillary channel 2L is configured. The second substrate 22 of the present embodiment covers the concave-convex structure 212 and the concave portion 213 on the surface of the first substrate 21 without covering the concave portion 211 that forms the blood supply unit 2D. The first substrate 21 and the second substrate 22 are bonded by pressure bonding, ultrasonic bonding, or the like. At this time, the bonding strength of the first substrate 21 and the second substrate 22 can be improved by performing oxygen plasma treatment or ultraviolet irradiation treatment on the bonding surfaces.

  The measurement electrode 3 that is a measurement sensor portion is embedded in a surface 22 a of the second substrate 22 that faces the concavo-convex structure 212.

  The measurement electrode 3 is embedded in a surface 22a of the second substrate 22 facing the concavo-convex structure 212 and contacts the plasma component separated by the capillary small flow path 2L1. As shown in FIG. 2 and the like, the measurement electrode 3 of this embodiment includes a working electrode 31 such as a carbon electrode, a counter electrode 32 such as a platinum electrode, and a reference electrode 33 such as a silver / silver chloride electrode. Is a three-electrode type. Each of the electrodes 31 to 33 is formed in a substantially band shape, and as shown in FIGS. 3 and 4, the plasma contact surface (lower surface) of each of the electrodes 31 to 33 is formed on the back surface of the second substrate 22 (on the uneven structure 212. It is embedded so as to be flush with the opposing surface 22a). The tips of the electrodes 31 to 33 extend partway through the capillary small flow path 2L1. The other end extends from the plasma separator 2 to the outside, the other end is connected to an external connection terminal (not shown), and the external connection terminal is connected to the information processing device 4.

  Therefore, the first substrate 21 and the second substrate 22 are subjected to hydrophilic treatment so that at least a part of the capillary small flow path 2L1 becomes a hydrophilic region. The hydrophilic treatment includes oxygen plasma treatment or ultraviolet treatment.

  Regarding the first substrate 21, as shown in FIGS. 3 and 4, at least the inner surface of the opening of the concavo-convex structure 212 (upper inner surface of the concavo-convex structure 212 in FIG. 3) 212 m is subjected to hydrophilic treatment. . The region where the hydrophilic treatment of the concavo-convex structure 212 is performed is determined by the condition of the hydrophilic treatment, but in this embodiment, a predetermined value is given from the inner surface 212 m of the opening of the concavo-convex structure 212, specifically from the upper opening of the concavo-convex structure 212. The hydrophilic treatment is performed up to the position (in the present embodiment, the substantially upper half inner surface of the concavo-convex structure 212). On the other hand, the bottom inner surface of the concavo-convex structure 212 (the lower inner surface of the concavo-convex structure 212 in FIG. 3) 212n (a part other than the inner surface 212m of the opening, that is, the substantially lower half of the concavo-convex structure) is not hydrophobic. It is sex.

  On the other hand, regarding the second substrate 22, as shown in FIG. 3 and the like, the surface 22a (the back surface of the second substrate 22) that faces the concavo-convex structure 212 when the first substrate 21 and the second substrate 22 are brought into close contact with each other. The whole is subjected to hydrophilic treatment.

  In the state in which the capillary small channel 2L1 is formed by bringing the first substrate 21 and the second substrate 22 into close contact with each other, the shape of the portion X subjected to the hydrophilic treatment in the cross section of each capillary small channel 2L1 is a blood cell component. The shape is such that only the plasma component is allowed to pass through by capillary action without passing through.

Specifically, in a cross section perpendicular to the flow path direction of the capillary small flow path 2L1, as shown in FIG. 4, a substantially downwardly-coordinated structure constituted by the opening inner surface 212m of the concavo-convex structure 212 and the back surface 22a of the second substrate 22 is formed. A portion having a letter shape is a hydrophilic region X. In FIG. 4, the hydrophilic region X is a portion indicated by a thick line. The cross-sectional area of the virtual flow path (flow path having a substantially rectangular cross section) defined by the hydrophilic region X having a generally downward U-shape is such that only the plasma component passes without passing the blood cell component. It is trying to become. In terms of erythrocytes, the size is approximately disk-shaped with a diameter of about 7 μm and a thickness of 2 μm. The cross-sectional area of the virtual channel is a cross-sectional area that cannot pass even if the red blood cells are deformed to such an extent that they do not hemolyze. As described above, if the opening inner surface 212m of the concavo-convex structure 212 is, for example, 3 μm from the upper opening end, the cross-sectional area is 6 μm ² .

  Further, the surface of the blood supply part 2D formed by the first substrate 21 is also subjected to hydrophilic treatment. That is, the same hydrophilic treatment as that applied to the concavo-convex structure 212 or the like is also applied to the inner surface of the concave portion 211. Thus, when blood is dropped onto the blood supply unit 2D, the blood spreads in the width direction in the blood supply unit 2D, and the plurality of capillary small streams are uniformly distributed without concentrating the blood at the inlets of some capillary small channels 2L1. It can be distributed to the path 2L1, and clogging of blood can be prevented at the inlet of the capillary small flow path 2L1.

<Effect of this embodiment>
According to the blood analyzer 100 according to the present embodiment configured as described above, the blood cell component has the shape of the portion X subjected to the hydrophilic treatment in the cross section of the inlet portion (capillary small channel 2L1) in the capillary channel 2L. Since the shape does not pass, it is possible to prevent the blood cell component from entering the flow channel at the inlet portion of the capillary flow channel 2L, and to separate the plasma component from the blood and introduce it into the capillary flow channel 2L. In addition, in the structure in which a rough rectangular wave-shaped uneven structure 212 is formed on the first substrate 21 and the second substrate 22 is brought into close contact with the first substrate 21 to form at least an inlet portion in the capillary channel 2L. Since it is possible to add hydrophilicity to the capillary channel 2L simply by subjecting at least the inner surface 212m of the concave-convex structure 212 and the surface 22a of the second substrate 22 facing the concave-convex structure 212, plasma separation can be achieved. The construction and manufacture of the vessel 2 is simple. Furthermore, according to the plasma separator 2 of the present embodiment, most (approximately 100%) of plasma components can be separated from blood, so that the measurement accuracy of measurement components such as uric acid can be improved.

<Other modified embodiments>
The present invention is not limited to the above embodiment.
For example, in the above-described embodiment, a description has been given of a mode in which the groove of the concavo-convex structure 212 is deep and no hydrophilic treatment is performed up to the bottom. The entire structure 212 may be subjected to hydrophilic treatment). At this time, the width of the concave groove of the concavo-convex structure 212 is 3 μm, for example, and the depth is 3 μm, for example.

  Further, regarding the hydrophilic treatment of the embodiment, in addition to the hydrophilic treatment by irradiation with oxygen plasma and ultraviolet rays, for example, surface modification is performed using poly L lysine having a molecular weight of 30,000 or more, an amine, etc. You may make it improve. As a result, the plasma separation rate can be increased, and a large number of plasma components can be obtained in a short time, which not only improves the analysis accuracy but also enables the measurement time to be shortened. That is, the time required for the separation of plasma components can be as short as 5 to 10 seconds, and about 500 nanoliters (nl) can be obtained as the amount of plasma components. Ingredients can be obtained.

  Furthermore, in the said embodiment, while measuring electrode 3 is embed | buried in the 2nd board | substrate 22, it is comprised so that the measuring electrode 3 may be located in the middle of the capillary small flow path 2L1, but it shows in FIG. As described above, it is embedded in the second substrate 22 or in the space formed by the first substrate 21 and the second substrate 22 downstream of the capillary small flow path 2 </ b> L <b> 1 without being embedded in the second substrate 22. Anyway.

  In addition, in the embodiment, the second substrate 22 does not cover the blood supply unit 2D of the first substrate 21, but the second substrate 22 supplies the blood supply of the first substrate 21 as shown in FIG. A blood passage hole 221 communicating with the blood supply unit 2D may be formed in the second substrate 22 while being arranged to cover the unit 2D. At this time, it is conceivable that the blood passage hole 221 has a shape in which the opening is narrowed toward the blood supply unit 2D. In this way, the inner surface of the blood passage hole 221 is tapered, and the blood supply unit 2D is made as small as possible to facilitate the blood to be distributed to the plurality of capillary small channels 2L1, while the blood is supplied to the blood supply unit 2D. It can be made easy to supply.

  Regarding the capillary channel, in the embodiment, a plurality of capillary small channels in which one end communicates with the blood supply unit and substantially linear channels are arranged in parallel to each other; It consists of a large capillary channel that communicates with the end, but consists only of a plurality of capillary channels that have one end communicating with the blood supply section and substantially linear channels arranged in parallel with each other. May be.

  In addition, the measurement sensor unit of the embodiment uses a three-electrode type measurement electrode, but in addition, a two-electrode type measurement electrode composed of a working electrode and a counter electrode may be used. These sensors may be used.

  In addition, it goes without saying that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 100 ... Blood analyzer 2 ... Plasma separator 3 ... Measurement electrode 4 ... Information processing device 2L ... Capillary flow path 2L1 ... Inlet part 21 of capillary flow path ... No. 1 substrate 212 ... uneven structure 212m ... opening inner surface 212n of uneven structure ... bottom inner surface 22 of uneven structure ... second substrate 22a ... surface X facing the uneven structure 212 ... capillary tube Part of the flow path where hydrophilic treatment has been applied

Claims (3)

A plasma separator that introduces blood into a capillary channel formed therein and separates plasma components from the blood,
A first substrate having a concavo-convex structure forming at least an inlet portion in the capillary channel on the surface;
A second substrate that is provided in close contact with the first substrate and forms an inlet portion in the capillary channel with the concavo-convex structure;
A hydrophilic treatment is applied to the inner surface of the opening of the concavo-convex structure of the first substrate and a surface of the second substrate facing the concavo-convex structure, and a hydrophobic treatment is applied to the inner surface of the bottom surface of the concavo-convex structure,
In a state where the first substrate and the second substrate are brought into close contact with each other to form the inlet portion in the capillary channel, the shape of the portion subjected to the hydrophilic treatment in the cross section of the inlet portion in the capillary channel is a blood cell A plasma separator that allows plasma components to pass through by capillary action without passing the components.   The plasma separator according to claim 1, further comprising a blood supply unit communicating with the capillary channel, wherein a surface of the blood supply unit is subjected to a hydrophilic treatment. A plasma separator according to claim 1 or 2,
An electrode for measurement in contact with the plasma component separated by the plasma separator,
A blood analyzer in which the measurement electrode is embedded in a surface of the second substrate facing the concavo-convex structure and contacts a plasma component separated by the capillary channel.