JP4509632B2 - Blood cell separation structure - Google Patents

Description

The present invention relates to a flow path for causing a fluid to proceed by capillary force , and a blood cell separation structure for easily separating a solid component (blood cell) and a liquid component (plasma) of blood using the same.

Recently, the use of microchannels in devices on structures such as electrophoretic structures and blood component measurement structures has become popular, and Japanese Patent Application Laid-Open No. 2003-83958 includes a microneedle-like puncture device. A blood component testing system is disclosed. Japanese Patent Application Laid-Open No. 2003-83958 requires a combination of centrifugation methods, and by using centrifugal force, it is possible to control the movement of the liquid, but it takes time and for the purpose of centrifugation. Configuration is required.
On the other hand, in Japanese Patent Laid-Open No. 2001-281233. Channel to a combination of the channel we realize quantification of liquid volume is shown.

Japanese National Patent Publication No. 5-510484 JP 2001-281233 A JP 2003-83958 A

By the way, the method of manipulating a fluid using a flow path is not limited to combining a plurality of flow paths and performing synthesis, separation, and quantification of a fluid as shown in the above-mentioned publication. It is necessary to incorporate a separator,
When separating a solid component and a liquid component of blood, the centrifugal method requires a centrifugal device, and the separation time becomes long. Further, the filter separation method requires pressurization, and there is a problem of hemolysis depending on the situation.
The problem to be solved is that the solid and liquid components of blood cannot be easily separated at high speed and at low cost. Chip-type fluid processing that is more compact, portable, and can be used for various types of measurement and inspection. In the current situation where devices are desired, the above-mentioned problems are great.

The present invention separates blood solid components and liquid components easily and quickly at low cost by the structure provided in the flow channel after largely separating the solid components and liquid components of the blood with an aggregating agent and an aggregation accelerator. Is the most important feature.
A fluid in the present invention, preferably comprise a particulate, blood, urine, sweat, semen, called interstitial fluid or the like Ru is illustrated.
In the present invention, the flow path in which the fluid travel direction is narrow is a predetermined area in the travel direction, that is, the cross-sectional area of the flow path travel direction end that reaches the operation region to be quantified or processed is the flow path. 1 to 99% smaller than the cross-sectional area of the liquid input portion, and the side surface of the flow path up to that point has a taper shape, or the cross-sectional area is small only in the vicinity of the end portion in the traveling direction It may be.
Sectional area of the end portion in the traveling direction of the channel, for example, 0.0005mm ² ~0.001mm ^2, the cross-sectional area of the input-side end, for example, 0.1 mm ² 2.5 mm ² is shown.

The step of agglutinating blood cells in the present invention is, for example, forming an aggregate with a polymer or the like that chemically or physically reacts with blood cells.
As the hemagglutinating agent, for example, a combination of an aggregating component and a coagulation accelerating component is preferable in that it does not dissolve blood and quickly aggregates.
The size of the agglomerate is preferably larger, but for example, a particle agglomerate having a diameter of 0.1 mm to 2 mm is preferred.
The step of promoting the aggregation of blood cells in the present invention is, for example, chemically or physically accelerating the reaction between the blood cells and the aggregating agent and further tightening the aggregates.
The step of decelerating the progression of blood in the present invention is to temporarily reduce the progression speed by, for example, providing projections on the wall surfaces on both sides of the channel to reduce the cross-sectional area of the channel. .
The step of automatically advancing the separated plasma in the present invention is, for example, a structure utilizing the property that the separation liquid automatically advances in the direction of smaller cross-sectional area by gradually reducing the cross-sectional area of the flow path. That is.
In addition, in order to advance or to assist the progress, a porous material such as filter paper or porous ceramics can be arranged to promote the progress due to the suction ability provided by the porous material. Examples of this porous material include non-woven fabrics and sponges in addition to those described above.
The adjusting means in the present invention is a state in which at least unnecessary components in the fluid can be aggregated, solidified, amplified, or increased, and can be captured, deformed, and altered in a part of the downstream flow path. If it is means for that, it is not limited to the above.
The flow path is not limited to the arrangement of the side protrusions and bottom protrusions, and various physical properties such as a special fluid of unnecessary components obtained by the adjusting means, a depression provided in the bottom part, a special charged area, a hydrophobic area, etc. The method is not limited to this as long as it can be captured, altered, and deformed by a technique.
The fractional processing in the present invention means that, for example, a part or all of the adjustment component is captured, deformed, altered, sieved, etc. Indicates that it is removed, reduced to an unnecessary amount, converted to an unnecessary object, altered, or partially bypassed later, but at least forms an unnecessary state for the purpose. There is no particular limitation as long as the processing is not performed.

The present invention makes it possible to control the flow at a speed in accordance with fluid processing, and to incorporate a measurement system and an operation system in the middle.
Moreover, there is an advantage that a solid component and a liquid component of blood can be separated easily and inexpensively simply by mixing a coagulant or the like with blood and introducing it into a separation channel.

In the present invention, by providing one or a plurality of protrusions having a width of 0.01 to 1 mm on both sides of a flow path having a thin traveling direction, a force that temporarily stops the fluid flow at the protrusions is received. For this reason, the flow rate of the fluid can be reduced.
By increasing the number of side protrusions, an arbitrary fluid speed is realized.
Furthermore, unnecessary particles can be captured by the bottom surface protrusions by the flow path in which one or a plurality of protrusions having a width of 0.01 to 0.1 mm are provided on the bottom surface of the flow path having a narrow traveling direction.
Further, by combining the side protrusions and the bottom protrusions, the side protrusions can cause the particles to stay on the bottom surface by the fluid whose speed has been reduced, and can be captured by the bottom protrusions, thereby realizing particle separation in the fluid.
By separating the solid component and the liquid component of the blood injected into the flow channel, and gradually reducing the cross-sectional area of the separated liquid component to the flow channel, it is automatically advanced to the structure ahead. A fast and inexpensive separation structure was realized.
Examples of the solid component in the present invention include erythrocytes, leukocytes, and platelets, and examples of the liquid component include serum and plasma.
In the present invention, it is preferable to form a particle mass having a higher specific gravity using a hemagglutinating agent for blood cell separation.

As the aggregating agent for agglutinating blood cells of blood, a polymer material that aggregates at a high speed without affecting the properties of blood is suitable, and the following components are exemplified as examples.
The aggregating component only needs to be positively charged in an aqueous solvent such as polycation. For example, poly-L - lysine, poly-L - arginine, polyacrylamide, poly-L - O carnitine, but Po Li ethyleneimine and a copolymer of them and the like are shown, but the present invention is not limited thereto. Further, polyethylene glycol, agarose , starch, PVA, polyvinyl pyrrolidone, ion exchange resin and the like may be contained in the polymer. In particular, an anion exchange resin or the like may be introduced.

As the accelerator for promoting the aggregation of blood cells, a material that accelerates the aggregation time, tightens the aggregate, and increases the liquid component of the blood is suitable. Examples thereof include the following components.

The coagulation promoting component may be at least a hydrophobic material, preferably a chain-like hydrophobic substance such as a lipid chain, such as oleic acid, stearic acid, palmitic acid, erucic acid, nervonic acid, linoleic acid, α-; linolene Acid, arachidonic acid, encosapentaenoic acid, docosapentaenoic acid, dihydroxystearic acid, cerebronic acid, ricinoleic acid, hydroxynervonic acid, hydnocarpsic acid, shoulmuric acid, gorulinic acid, lactobacillic acid, itaconic acid, tricosane diacid Derived from fatty acids such as crotonic acid, myristoleic acid, etc., oleyl group, stearyl group, palmityl group, erfrog group, nerbonel group, linolel group, α-; linolerel group, arachiduel group, encosapentael group, docosa It has a pentael group and other derivative groups derived from the above fatty acids. It shall are exemplified.
Among these, the combination of poly L lysine and oleyl group is suitable for the present invention in that it quickly and stably aggregates without lysing cells.

FIG. 1 shows an embodiment of the present invention.
FIG. 1 is a view from above, and shows a state in which the lid 10H is not provided, and is a cross-sectional view in the XX ′ direction with the lids in FIGS. 1B and 1C. The sectional view of YY 'direction was shown.
Reference numeral 11 denotes a blood cell sedimentation chamber, which has a size of about 10 mm <3> and has an inlet 22 at the top. 12 is a flow path, and its side surface has an inclination a of 1 to 5 degrees with respect to the traveling direction of the blood component. The width c of the connection surface between the flow channel 12 and the blood cell sedimentation chamber 11 is about 1 to 4 mm, and the width d of the connection surface between the flow channel 12 and the suction part 13 is about 0.1 to 1 mm.
Reference numeral 13 denotes a sucking portion that contains porous components such as blotting paper and filter paper for assisting the progress of blood components.
Reference numeral 14 denotes a blocking portion that attempts to advance the blood component to the flow path 12 in such a manner that the blood component overflows upward.
The blocking part 14 forms an oblique upper flow path for blood components, but it is only necessary that the blocking part 14 is provided above the blood cell sedimentation chamber 11 and has an angle of parallel or more.

Reference numerals 15 and 17 are speed reducers, and the width e is 0.01 to 0.1 mm, in order to temporarily reduce the blood traveling speed by partially reducing the cross-sectional area of the flow path. belongs to. There may be at least one deceleration bank 15, 17 at least.
Reference numerals 16 and 18 denote sedimentation steps, and the height b is set to 0.01 to 0.1 mm, and is a convex structure provided on the bottom surface of the flow path to capture unaggregated blood cells. belongs to. There may be at least one settling step 16, 18 at least.
Reference numeral 19 denotes a collecting flow channel for connecting the quantitative weighing chamber 20 and the flow channel 12. Reference numeral 20 denotes a quantitative weighing chamber, which is a reaction chamber for performing biochemical tests and the like, and the liquid component is quantified by the determined indoor area. The degree of wettability in the room and liquid components are introduced. There may be a case where a plurality of quantitative weighing chambers 20 are provided depending on the purpose.
Reference numeral 21 denotes a deaeration hole which is deaerated in order to introduce a liquid component into the quantitative weighing chamber 20.
22 is a inlet having, flocculants, diluent, a mouth for introducing whole blood or the like, the like provided for shielding cover constituting a case.
The blood cell sedimentation chamber 11 and the flow path 12 may be subjected to a hydrophilic treatment on the surface.
These regions are preferably formed as recesses in a chip-like substrate 10 having a size of 4 × 2 × 3 mm. It is preferable that the lid 10H is joined from above by an adhesive, ultrasonic welding or the like.
The base 10 is preferably made of PDMS, polypropylene, PET, polycarbonate, and the like, and the lid 10H is preferably made of the same material, but is not limited thereto. Note that the flow path surface, the operation region surface, and the like on the substrate 10 may be subjected to plasma treatment as necessary.

The operation will be described with reference to FIG.
First, as shown in FIG. 2A, 5 to 20 ml of whole blood and 5 to 20 of blood coagulant are introduced from the inlet 22.
K to put ml. The dose is filled to such an extent that it exceeds the surface of the blocking portion 14 that is cut in the oblique direction. Whole blood and blood aggregating liquid may be supplied independently.
The mixed liquid L of whole blood and blood agglutinating agent that has been input is a liquid mixture in which red blood cells, white blood cells, and platelets are aggregated and precipitated while N1 overflows. What,
It flows in (FIG. 2 (b)).
The flow path 12 has a taper with respect to the advancing direction, and because of the taper, the capillary force acts strongly, and the mixed component tends to travel through the flow path 12 by the combined force V of the suction force of the suction portion 13. To do.
At this time, the blood cell agglutination action takes some time, and thus flows into the flow path 12 beyond the blocking portion 14. Therefore, in order to promote aggregation and sedimentation of blood cells and the like, the blood progression speed is reduced in the deceleration bank 15. Decelerate. That is, in the speed-reduction bank 15, the speed-reduction bank protrudes in the flow path 12, and since the cross-sectional area of a flow path reduces, advancing speed falls temporarily (FIG.2 (c)). The speed reduction rate at that time is approximately 10% to 90%, but varies depending on the amount of protrusion.

Due to this speed reduction, agglutination and precipitation reaction of components such as blood cells by the aggregating agent proceeds, and the heavy agglomerate N2 is precipitated at the precipitation step 16 portion.
When the blood component M1 reaches the next deceleration bank 17 beyond the sedimentation step 16, the progression of the blood component M1 is decelerated as in the deceleration bank 15, and the aggregation of N2 is promoted by further precipitation of components such as blood cells. Aggregate N2 precipitates at the corner of the precipitation step 18 (FIG. 2 (c)). Since the flow path of the mixture of the coagulant and blood is slowed by the deceleration bank in this way, the agglutination reaction proceeds and the aggregate N2 such as blood cells overflowing from the sedimentation chamber is captured by the sedimentation steps 16 and 18. Therefore, blood cell components and the like are removed, blood plasma, blood component M2 close only serum is housed in blotting portion 13 (Figure 2 (d)).
The number of deceleration dams may be as long as it is necessary for separating and removing blood cells and the like flowing into the flow path 12 beyond the blocking portion 14, but is not limited thereto and may be determined as appropriate.

(Preparation method of flocculant + accelerator)
Poly-L-lysine (molecular weight 30000-70000, manufactured by Sigma) and oleic acid N-hydroxysuccinimide (manufactured by Sigma) were mixed in a DMSO (manufactured by Sigma) solvent in a molar ratio of 1: 1, The reaction was allowed to proceed for 1 hour at room temperature. Thereafter, it was adjusted to a concentration of 370 μM with PBS.

15 μL of the flocculant was added to 15 microliters (μL) of blood and dropped on a slide glass. The photo was taken after standing at room temperature for 2 minutes. (Figure 3)
From the left, the photo shows PBS added, flocculant + accelerator added, and only flocculant added.
When an aggregating agent, an aggregating agent + accelerator was added, the clotting effect was already noticeable within a few seconds after the addition, and the separation of hemagglutinating clot and plasma was observed. In the case of adding an aggregating agent, unaggregated blood cells were observed in the separated plasma, but when an aggregating agent + accelerator was added, almost no unaggregated blood cells were observed.
Poly-L-lysine (molecular weight 30000-70000, manufactured by SIGMA) was used as the flocculant, and oleyl group (manufactured by SIGMA) was used as the accelerator.

Since the present invention separates blood cells from blood by simply dropping a small amount of blood at home, it is suitably used for blood biochemical tests, immunological tests, cancer diagnosis, infectious disease diagnosis, and the like . This structure that can separate blood cells easily, at high speed and at low cost can be used industrially.

It is the figure which showed one Example of this invention. It is a figure for demonstrating operation | movement of this invention. It is a figure for demonstrating operation | movement of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Base 10H Cover 11 Blood cell sedimentation chamber 12 Flow path 13 Suction part 14 Blocking part 15, 17 Deceleration bank 16, 18 Sinking step 19 Sampling flow path 20 Quantitative weighing chamber 21 Deaeration hole 22 Inlet

Claims (3)

The substrate (10) has a configuration in which the cross-sectional area on the inlet side is large and the cross-sectional area decreases toward the outlet side, and a protrusion for temporarily stopping or decelerating the flow of fluid on the inner surface of the inlet side A flow path (12) provided with a suction part (13) on the outlet side,
A blood cell sedimentation chamber (11) disposed on the inlet side of the flow channel (12) and capable of temporarily storing a mixture of blood and blood coagulation components, and the flow channel (12 in the blood cell sedimentation chamber (11)) ) In the direction of the inlet side of the blood vessel, and is formed by a blocking portion (14) installed so that the mixed component from which the blood cells have been removed overflows , and the mixed component is input into the blood cell sedimentation chamber (11). The mixed component that has been introduced from the mouth (22) until it overflows the upper part of the blocking part (14) and has overflowed the upper part of the blocking part (14) is taken into the flow path (12) by capillary force. A blood cell separation structure that separates blood coagulation components and mixed components by rarely moving toward the outlet . The blood cell separation structure according to claim 1, wherein the sucking portion (13) contains a nonwoven fabric and blotting paper. The blood cell separation structure according to claim 1, wherein the blood coagulation component is poly-L-lysine, poly-L-arginine, polyacrylamide, poly-L-ornithine, polyethyleneimine, and a copolymer thereof.

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