Inspection flow path device and inspection apparatus

An inspection flow path device according to the present disclosure comprises: a first flow path device having a plate-like shape and including a pair of first surfaces located opposite to each other in a thickness direction and a first flow path located inside and including a first opening located in the pair of first surfaces and a branch flow path; and a second flow path device having a plate-like shape and translucency and including a pair of second surfaces located opposite to each other in a thickness direction and a second flow path located inside and including a second opening located in the pair of second surfaces; wherein one of the pair of first surfaces of the first flow path device is located on one of the pair of second surfaces of the second flow path device, and the first opening and the second opening are connected to each other.

CROSS-REFERENCE TO RELATED APPLICATION

The present application is a National Phase entry based on PCT Application No. PCT/JP2019/002556, filed on Jan. 25, 2019, entitled “INSPECTION FLOW CHANNEL DEVICE AND INSPECTION APPARATUS”, which claims the benefit of Japanese Patent Application No. 2018-013698, filed on Jan. 30, 2018, entitled “INSPECTION FLOW CHANNEL DEVICE AND INSPECTION APPARATUS”. The contents of which are incorporated by reference herein in their entirety.

FIELD

Embodiments of the present disclosure relate generally to an inspection flow path device and an inspection apparatus.

BACKGROUND

A separation and recovery of microparticles are conventionally known. A measurement of microparticles is known.

SUMMARY

An inspection flow path device and an inspection apparatus are disclosed. In one embodiment, an inspection flow path device comprises a first flow path device and a second flow path device. The first flow path device has a plate-like shape and includes a pair of first surfaces located opposite to each other in a thickness direction of the first flow path device and a first flow path located inside the first flow path device and including a first opening located in the pair of first surfaces and a branch flow path. The second flow path device has a plate-like shape and translucency and includes a pair of second surfaces located opposite to each other in a thickness direction of the second flow path device and a second flow path located inside the second flow path device and including a second opening located in the pair of second surfaces. One of the pair of first surfaces is located on one of the pair of second surfaces, and the first opening and the second opening are connected to each other.

In one embodiment, an inspection apparatus includes the inspection flow path device described above and an optical sensor irradiating the second flow path with light and receiving light passing through the second flow path.

DETAILED DESCRIPTION

Examples of an inspection flow path device and an inspection apparatus according to embodiments of the present disclosure are described with reference to the drawings. In the present disclosure, a rectangular coordinate system (X, Y, Z) is defined for descriptive purposes to define a positive side in a Z axis direction as an upper side, however, in the present disclosure, any direction may be the upper side or a lower side. The following contents illustrate embodiments of the present disclosure, and the present disclosure is not limited to these embodiments.

FIG. 1andFIG. 2schematically illustrate an inspection flow path device1.FIG. 1is a top view of the inspection flow path device1, andFIG. 2is a cross-sectional view of the inspection flow path device1cut along an A-A line inFIG. 1.

When a fluid (a sample) to be inspected is flowed in the inspection flow path device1, the inspection flow path device1can separate and recovery a specific component (microparticles) in the sample, and measure the recovered specific component (microparticles). For example, the inspection flow path device1can separate and recover white blood cells (leukocyte) from blood, and measure the number of white blood cells included in the blood. The inspection flow path device1includes a first flow path device2and a second flow path device3connected to the first flow path device2.

FIG. 3schematically illustrates the first flow path device2.FIG. 3is a plan view of the first flow path device2when seen from an upper surface transparently.

The first flow path device2can separate and recovery microparticles in a fluid (sample). The first flow path device2includes a first flow path4. The first flow path4includes a main flow path (first main flow path)5and a branch flow path (first branch flow path)6branching from the first main flow path5. In the first flow path device2in the present disclosure, the fluid flowing in the first flow path device2flows into the first main flow path5, and only microparticles (second particles) different from the specific microparticles (first particles) flow from the first main flow path5into the first branch flow path6, thus the specific microparticles (first particles) can be separated. When the microparticles (second particles) different from the specific microparticles (first particles) flow into the first branch flow path6, the first flow path device1can also separate the different microparticles (second particles).

The first branch flow path6is designed so that only the second particles are branched and flow therein, however, only the second particles are not necessarily branched. That is to say, microparticles different from the second particles may flow into the first branch flow path6in some cases.

FIG. 4schematically illustrates a process of separating the first particles and the second particles.FIG. 4is an enlarged view of a broken line section inFIG. 3. Herein, a large circle inFIG. 4indicates the first particle P1and a small circle indicates the second particle P2. A thick arrow along the X axis direction indicates a main stream and a thin arrow along the Y axis direction indicates a “pressing flow” described hereinafter. A hatched region inFIG. 4indicates a “lead-in flow” described hereinafter.

The first flow path4in the present disclosure includes one first main flow path5and the plurality of first branch flow path6connected to one side of the one first main flow path5. In the first flow path device2, a sectional area and length of each of the first main flow path5and the first branch flow path6, a flow rate of the sample and the like are adjusted, thus the “lead-in flow”, which flows from the first main flow path5into the first branch flow path6can be generated in the first main flow path5. The first flow path device2generates the pressing flow, which can press the sample flowing in the first main flow path5against a side of the first branch flow path6, in the first flow path4. As a result, as illustrated inFIG. 4, a width of the lead-in flow is set to larger than a barycentric position of the specific microparticle (the first particle P1) flowing in the sample and smaller than a barycentric position of the other microparticle (the second particle P2), thus the other microparticles (the second particle P2) can be lead in the first branch flow path6. At this time, a width of the first branch flow path6is set to smaller than a size of the specific microparticle (the first particle P1) flowing in the sample and larger than a size of the other microparticle (the second particle P2), thus the other microparticles (the second particle P2) can be lead in the first branch flow path6.

The first flow path device2in the present disclosure is particularly intended to separate red blood cells (erythrocyte) and white blood cells (leukocyte) in blood. A barycentric position of the red blood cell in the blood is located 2 to 2.5 μm from an edge thereof, for example, and the size of the red blood cell is 6 to 8 μm, for example. A barycentric position of the white blood cell is located 5 to 10 μm from an edge thereof, for example, and the size of the white blood cell is 10 to 30 μm, for example. In this case, the first main flow path5may have the sectional area ranging from 300 μm2to 1000 μm2and the length ranging from 0.5 mm to 20 mm, for example. The first branch flow path6may have the sectional area ranging from 100 μm2to 500 μm2and the length ranging from 3 mm to 25 mm, for example. The flow rate in the first flow path4may be equal to or larger than 0.2 m/s and equal to or smaller than 5 m/s, for example. As a result, the width of the lead-in flow can be set equal to or larger than 2 μm and equal to or smaller than 15 μm, for example, thus the red blood cell and the white blood cell in the blood can be separated.

The first flow path4further includes a first recovery flow path7connected to the first main flow path5, and can recovery the first particles P1. In the first flow path4in the present disclosure, the first particles P1can be recovered in the first recovery flow path7using the pressing flow.

The first flow path4may include a first disposal flow path7′ connected to the plurality of first branch flow paths6. The first disposal flow path7′ may recover or dispose of the separated second particles P2. When the second particles P2are recovered by the plurality of first branch flow paths6, one first disposal flow path7′ to which the plurality of first branch flow paths6are connected functions as a flow path for recovering the second particles P2. The fluid flowing to an end of the first main flow path5may be disposed of.

The first flow path device2is a plate-like member. The first flow path4is located inside the plate-like member. The first flow path device2includes a pair of first surfaces8located opposite to each other in a thickness direction (the Z axis direction). The first flow path4is opened in the pair of first surfaces8. In other words, the first flow path4includes a plurality of first openings9located in the pair of first surfaces8.

In the present disclosure, one of the pair of first surfaces8is defined as a first upper surface10and the other one thereof is defined as a first lower surface11for descriptive purposes. In the pair of first surfaces8, the first upper surface10is a surface located on a positive side of the Z axis and the first lower surface11is a surface located on a negative side of the Z axis. In the present disclosure, at least one of the plurality of first openings9is located in the first lower surface11.

The plurality of first openings9include a first flow inlet (first sample flow inlet)12through which the sample flows into at least the first main flow path5, a first flow outlet (a first sample flow outlet)13through which the first particles P1are recovered from the first recovery flow path7, and at least one first disposal flow outlet14through which constituents in which the first particles P1are removed from the sample are recovered. Included in the present disclosure is a first pressing flow inlet15through which the fluid of the pressing flow for pressing the sample against the first branch flow path6side flows. In the present disclosure, the first disposal flow outlet14is connected to the first main flow path5and the first disposal flow path7′. The fluid flowing out through the first disposal flow outlet14is recovered through a through hole14′ formed in the second flow path device3.

A planar shape of the first flow path device2in the present disclosure is a rectangular shape. Each of the first surfaces8in the present disclosure is a flat surface. A planar shape of the first flow path device2is not limited to the rectangular shape. Each of the first surfaces8in the present disclosure is not limited to the flat surface. In the first surfaces8, shapes of the first upper surface10and the first lower surface11may be different from each other.

The first flow path device2may be formed of a material of polydimethylsiloxane (PDMS) or acrylic (PMMA), for example. A thickness of the first flow path device2may be equal to or larger than 1 mm and equal to or smaller than 5 mm, for example. The planar shape of the first flow path device2may have a short side with a length equal to or larger than 10 mm and equal to or smaller than 30 mm and a long side with a length equal to or larger than 10 mm and equal to or smaller than 50 mm, for example. The first flow path device2can be formed by preparing two substrates, forming a groove in one of the two substrates, and attaching the two substrates to each other to cover the groove, for example.

The second flow path device3is a flow path for measuring the specific microparticles separated and recovered in the first flow path device2. As illustrated inFIG. 2, the second flow path device3includes a second flow path16connected to the first flow path4in the first flow path device2. The second flow path device3has translucency. As a result, the second flow path device3can flow the specific microparticles separated and recovered in the first flow path device2to the second flow path16and the specific microparticles can be measured by using an optical sensor described hereinafter. Specifically, the optical sensor measures intensity of light passing through the second flow path16, thereby measuring the specific microparticles.

The second flow path device3is a plate-like member. The second flow path16is located inside the plate-like member. The second flow path device3includes a pair of second surfaces17located opposite to each other in a thickness direction (the Z axis direction). The second flow path16is opened in the pair of second surfaces17. In other words, the second flow path16includes a plurality of second openings18located in the pair of second surfaces17.

In the present disclosure, one of the pair of second surfaces17is defined as a second upper surface19and the other one thereof is defined as a second lower surface20for descriptive purposes. In the pair of second surfaces17, the second upper surface19is a surface located on a positive side of the Z axis and the second lower surface20is a surface located on a negative side of the Z axis.

A planar shape of the second flow path device3in the present disclosure is a rectangular shape. Each of the second surfaces17in the present disclosure is a flat surface. A planar shape of the second flow path device3is not limited to the rectangular shape. Each of the second surfaces17in the present disclosure is not limited to the flat surface. In the second surfaces17, shapes of the second upper surface19and the second lower surface20may be different from each other.

The second flow path device3may be formed of acrylic (PMMA) or cycloolefin polymer (COP), for example. A thickness of the second flow path device3may be equal to or larger than 0.5 mm and equal to or smaller than 5 mm, for example. The planar shape of the second flow path device3may have a short side with a length equal to or larger than 10 mm and equal to or smaller than 30 mm and a long side with a length equal to or larger than 20 mm and equal to or smaller than 50 mm, for example. The second flow path device3can be formed by preparing two substrates, forming a groove in one of the two substrates, and attaching the two substrates to each other to cover the groove, for example.

FIG. 5schematically illustrates the first flow path device2and the second flow path device3.FIG. 5is an enlarged view of a broken line section inFIG. 2.

In the second flow path device3in the present disclosure, at least one of the plurality of second openings18is located in the second upper surface19. The first flow path device2is located on the second upper surface19via the first lower surface11, and the first opening9located in the first lower surface11and the second opening18located in the second upper surface19are connected to each other. Accordingly, in the inspection flow path device1in the present disclosure, the first flow path device2is directly connected to the second flow path device3, and the process from the separation and recovery to the measurement of the specific microparticles in the sample can be continuously performed, thus a work efficiency can be improved. The plate-like first flow path device2and second flow path device3are located to be stacked in the thickness direction, thus the inspection flow path device1can be minimized.

The second upper surface19of the second flow path device3in the present disclosure includes a first region21and a second region22. In a plan view, the second flow path16in the second flow path device3is located to extend from the first region21to the second region22, and in a transparent plan view, the second flow path16overlaps with the first region21and the second region22. The first flow path device2is located only on the first region21in the second flow path device3. As a result, the second flow path16is exposed to the second region22, thus the second region22can be used as a measurement region.

In the inspection flow path device1, a member which can reflect light may be located on the second region22as described hereinafter.

The first flow path device2may be formed of a material different from that of the second flow path device3. In the present disclosure, for example, the first flow path device2is formed of PDMS and the like, and the second flow path device3is formed of COP and the like.

As is the case in the present disclosure, the first flow path device2may be located on an upper side of the second flow path device3. Specifically, the first flow path device2may be located on the second upper surface19of the second flow path device3. As a result, the specific microparticles in the sample separated and recovered in the first flow path device2can be flowed into the second flow path device3also using gravity, and a retention of the recovered microparticles midway through the flow path can be reduced.

The present disclosure does not exclude an embodiment in which the first flow path device2is located on the second lower surface20of the second flow path device3.

The plurality of second openings18include a second sample flow inlet23through which the sample flows into the second flow path16and a second sample flow outlet24through which the sample is recovered from the second flow path16. The second sample flow inlet23is located in the second upper surface19, and is connected to the first sample flow outlet13in the first flow path device2. The second sample flow outlet24is located in the second lower surface20. As a result, by using the gravity, the sample can be easily flowed from the first flow path device2through the second sample flow inlet23and the sample can be easily recovered in the second sample flow outlet24.

An opening of the second sample flow inlet23may be larger than an opening of the first sample flow outlet13as illustrated inFIG. 5. As a result, the retention of the sample can be reduced in a connection part between the first flow path device2and the second flow path device3. A size of the second sample flow inlet23may be equal to or larger than 1 mm and equal to or smaller than 3 mm, for example. A size of the first sample flow outlet13may be equal to or larger than 1 mm and equal to or smaller than 3 mm, for example.

The second flow path16includes a vertical part25connected to the second sample flow inlet23(the second opening18) and extending in the thickness direction and a planar part26connected to the vertical part25and extending along a planar surface direction. The second flow path16includes the vertical part25, thereby being able to reduce the retention of the sample including the specific microparticles in the connection part between the second flow path16and the first flow path4. The second flow path16includes the planar part26, thereby being able to retain the sample including the specific microparticles, thus a stable measurement can be achieved.

A width of the vertical part25may be equal to or larger than 0.5 mm and equal to or smaller than 2 mm, for example, and a width of the planar part26may be equal to or larger than 1 mm and equal to or smaller than 6 mm, for example. A length of the vertical part25may be equal to or larger than 0.5 mm and equal to or smaller than 1 mm, for example, and a height of the planar part26may be equal to or larger than 0.5 mm and equal to or smaller than 2 mm, for example.

FIG. 6andFIG. 7schematically illustrate the second flow path device3.FIG. 6is a plan view of the second flow path device3when seen from an upper surface transparently.FIG. 7is an enlarged view of a broken line section illustrated inFIG. 6. An A-A line inFIG. 6is the same as the A-A line inFIG. 1.

Part of the planar part26connected to at least the vertical part25may have a width larger than the vertical part25. As a result, the retention of the sample can be reduced in a connection part between the planar part26and the vertical part25.

The planar part26may further include a first planar part27connected to the vertical part25and a second planar part28connected to the first planar part27and having a width larger than the first planar part27. As a result, the first particles P1can be easily diffused. A width of the first planar part27may be equal to or larger than 0.5 mm and equal to or smaller than 3 mm, for example. A width of the second planar part28may be equal to or larger than 1 mm and equal to or smaller than 5 mm, for example. A width of the second planar part28may be twice or more and ten times or less than the first planar part27, for example. In the present disclosure, a connection part between the first planar part27and the second planar part28is gradually widened.

The second planar part28may have a height larger than the first planar part27. As a result, the first particles P1can be easily diffused. A height of the first planar part27may be equal to or larger than 0.2 mm and equal to or smaller than 1 mm, for example. The height of the second planar part28may be equal to or larger than 1 mm and equal to or smaller than 5 mm, for example.

The second flow path device3may further include, in addition to the second flow path16, a third flow path29connected to the second flow path16. The third flow path29may be connected to the planar part26of the second flow path16. The third flow path29has a function of sweeping away the sample reaching the planar part26by flowing gas, for example. As a result, the retention of the sample in the second flow path16can be reduced.

In the second flow path device3in the present disclosure, as illustrated inFIG. 5andFIG. 7, the third flow path29is located to be connected to the connection part between the vertical part25and the planar part26in the second flow path16.

One end of the third flow path29is connected to the second flow path16as described above. The other end of the third flow path29serves as a third opening30located in the pair of second surfaces17. In other words, the third flow path29includes a third opening30located in one of the pair of second surfaces17(in the present disclosure, the second upper surface19). The third opening30is an opening through which an extrusion fluid for sweeping away the sample is flowed in.

At least part of the third flow path29connected to the second flow path16may extend along an extension direction of the planar part26of the second flow path16as illustrated inFIG. 7.

At least part of the third flow path29connected to the second flow path16may have the same shape as at least part of the second flow path16connected to the third flow path29. As a result, a level difference occurring between the second flow path16and the third flow path29and the retention of the sample in the level difference can be reduced.

The third flow path29may include a plurality of extension parts31each extending in one direction and arranged in a direction intersecting with one direction. The third flow path29includes the extension parts31, thereby being able to reduce the sample flowing back from the second flow path16and leaked from the third opening30.

The first sample flow inlet (first flow inlet)12of the first opening9may be located in a surface (the first lower surface11in the present disclosure) similar to that of the first sample flow outlet (first flow outlet)13of the first opening9. In this case, the sample flows into the first flow path device2from below. As a result, the second particles P2can be sunk when a specific gravity of the second particles P2is larger than that of the first particles P1, thus the particles can be separated easily.

The second flow path device3may further include a fourth flow path32different from the second flow path16and the third flow path29as illustrated inFIG. 6. The fourth flow path32may include a plurality of fourth openings33located in the pair of second surfaces17. The fourth flow path32can function as a flow path in which the sample before the microparticles are separated flows. As a result, the sample is flowed into the second flow path device3before flowed into the first flow path device2, thus a foreign material and the like which have been mixed into the sample and the like to be injected can be previously reduced before flowed into a separation flow path.

The plurality of fourth openings33include a fourth flow inlet34and a fourth flow outlet35. The fourth flow inlet34is an opening through which the sample flows into the fourth flow path32. The fourth flow outlet35is an opening through which the sample flows from the fourth flow path32. The fourth flow inlet34is exposed outside, and the fourth flow outlet35is connected to the first sample flow inlet (first flow inlet)12of the first flow path device2.

The fourth flow inlet34and the fourth flow outlet35may be located in the second upper surface19. The above configuration has a significant effect that an operation such as an external connection can be performed from above. In the present disclosure, the fourth flow inlet34is located in the same surface as that of the second sample flow inlet23. In the present disclosure, the fourth flow outlet35is located in the same surface as that of the second sample flow inlet23. The fourth flow inlet34is located in the same surface as that of the third opening30.

The second flow path device3may further include a fifth flow path36different from the second flow path16, the third flow path29, and the fourth flow path32as illustrated inFIG. 6. The second flow path16is a flow path for flowing the specific microparticles separated and recovered in the first flow path device2as described above. This fifth flow path36can function as a flow path for correction. The fifth flow path36can flow a sample for correction different from the specific microparticles separated and recovered in the first flow path device2. As a result, it is possible to measure the second flow path16and the fifth flow path36in sequence every time the specific microparticles are measured to estimate the number of specific microparticles in accordance with a difference of light intensity of the flow paths16and36, thus an influence of deterioration of an optical sensor can be reduced.

The fifth flow path36includes a plurality of fifth openings37located in the pair of second surfaces17. The fifth openings37include a fifth flow inlet38and a fifth flow outlet39. The fifth flow inlet38is an opening through which a fluid for correction flows into the fifth flow path36. The fifth flow outlet39is an opening through which a fluid for correction flows from the fifth flow path36.

The fifth flow inlet38of the plurality of fifth openings37is located in the same surface as that of the third opening30. As a result, an operation of introducing and exhausting the fluid can be performed on the same surface from above. The fifth flow outlet39is located in the second lower surface20.

The second flow path device3may further include a sixth flow path40different from the second flow path16, the third flow path29, the fourth flow path32, and the fifth flow path36. The sixth flow path40includes a plurality of sixth openings41located in the pair of second surfaces17. The plurality of sixth openings41include a sixth flow inlet42and a sixth flow outlet43. The sixth flow inlet42is an opening through which a fluid of a pressing flow flows into the sixth flow path40. The sixth flow outlet43is an opening through which a fluid of a pressing flow flows from the sixth flow path40. The sixth flow inlet42is exposed outside, and the sixth flow outlet43is connected to the first pressing flow inlet15of the first flow path device2.

The third flow path29, the fourth flow path32, and the fifth flow path36can be formed in the manner similar to the second flow path16.

(Connection Structure of First Flow Path Device and Second Flow Path Device)

The first flow path device2is located on the second upper surface19of the second flow path device3as described above. Herein, a sheet member44may intervene between the first lower surface11of the first flow path device2and the second upper surface19of the second flow path device3. In other words, the inspection flow path device1may include the sheet member44located between the first flow path device2and the second flow path device3.

The sheet member44has a function as an intermediate layer for bonding hardly-adhesive materials. The sheet member44may be formed of a material such as silicone or PDMS, for example. The inspection flow path device1includes the sheet member44, thereby being able to absorb a waviness of a surface of a bonding surface. The sheet member44includes a plurality of through holes45. The plurality of through holes45may correspond to the plurality of first openings9. As a result, the fluid flows between the first flow path device2and the second flow path device3via the through holes45.

The first flow path device2and the second flow path device3in the present disclosure are connected via an adhesive agent applied to an upper surface and lower surface of the sheet member44. It is sufficient that the adhesive agent is a photo-curable resin hardened by ultraviolet or a thermoplastic resin, for example.

An inspection apparatus47is described next.

FIG. 8andFIG. 9schematically illustrate an inspection apparatus47.FIG. 8is a drawing of the inspection apparatus47with the same viewpoint as that inFIG. 2, and is a cross-sectional view.FIG. 9illustrates a block diagram of a whole image of the inspection apparatus47.

The inspection apparatus47includes the inspection flow path device1and an optical sensor48. The optical sensor48includes a light-emitting element49and a light receiving element50. As a result, firstly, the inspection flow path device1can separate the required microparticles (the first particles P1) from the sample. Then, the second flow path16is irradiated with light from the light-emitting element49of the optical sensor48to irradiate the microparticles flowing to the second flow path16of the inspection flow path device1with light, and the light receiving element50of the optical sensor48receives the light passing through the second flow path16, thus the microparticles can be measured. Specifically, the light passing through the second flow path16is diffused or absorbed, for example, by the microparticles (the first particles P1) in the sample, thus the light intensity decreases. As a result, a standard curve indicating a relationship between the sample including the particles, the number of which is already known, and an attenuation amount of the light is previously prepared and the attenuation amount of the light in the inspection apparatus47is checked against the standard curve, thus the microparticles in the sample can be measured.

The light-emitting element49may be a light emitting diode (LED), for example. The light receiving element50may be a photo diode (PD), for example. The light receiving element50includes a semiconductor substrate including a region of one conductivity type and a region of the other conductivity type on an upper surface, for example, and the light-emitting element49includes a plurality of semiconductor layers formed on the semiconductor substrate described above.

A mirror member51is located on the second upper surface19of the second flow path device3in the inspection flow path device1in the present disclosure. The light-emitting element49and the light receiving element50of the optical sensor48in the present disclosure are located on a side of the second lower surface20of the second flow path device3. Accordingly, the light receiving element50of the optical sensor48can receive the light passing through the second flow path16and reflected from the mirror member51. The mirror member51may be formed of a material such as aluminum or gold, for example. The mirror member51can be formed by an evaporation method, a sputtering method or the like, for example.

The inspection apparatus47further includes a first supply unit52supplying the sample, a second supply unit53supplying the fluid of the pressing flow, a third supply unit54supplying the extrusion fluid, and a fourth supply unit55supplying the correction fluid, all of which are connected to the inspection flow path device1. The first supply unit52is connected to the fourth flow inlet34. The second supply unit53is connected to the sixth flow inlet42. The third supply unit54is connected to the third opening30. The fourth supply unit55is connected to the fifth flow inlet38. The inspection apparatus47includes a controller, and the controller controls the first supply unit52, the second supply unit53, the third supply unit54, the fourth supply unit55, and the optical sensor48.

The present disclosure is not limited to the embodiments described above, however, various alternation and modifications, for example, should be possible within the scope of the present disclosure.

The above embodiments describe the example that one end of the fifth flow path36includes the fifth flow outlet39, however, as illustrated inFIG. 10andFIG. 11, one end of the fifth flow path36may be connected to the second flow path16. As a result, the fluid in the fifth flow path36can be injected into the second flow path16, thus the above configuration has a significant effect that a concentration of white blood cells in the second flow path16can be reduced.FIG. 10andFIG. 11are illustrated with the viewpoint similar to that inFIG. 6andFIG. 7.

The above embodiments describe the example of including the fifth flow path36and the sixth flow path40, however, the fifth flow path36may function as the sixth flow path40. That is to say, the fifth flow path36and the sixth flow path40may constitute one flow path to be connected to the first flow path4(the first pressing flow inlet15).

The above embodiments describe the example that the first flow path device2and the second flow path device3are bonded via the sheet member44. However, as illustrated inFIG. 12, the second flow path device3may further include a convex portion46located on the second upper surface19. The convex portion46may be inserted into the plurality of through holes45. As a result, the first flow path device2and the second flow path device3can be connected to each other. The adhesive agent is not necessary if the connection of the first flow path device2and the second flow path device3can be secured only with the convex portion46. In this case, the second flow path16and the second opening18may be located in the convex portion46.FIG. 12is illustrated with the same viewpoint as that inFIG. 5.

The first flow path device2and second flow path device3may be directed connected to each other. In this case, for example, the connection can be achieved by applying a silane coupling agent to at least one of the first lower surface11of the first flow path device2and the second upper surface19of the second flow path device3.

The above embodiments describe the example that the first flow path4is formed by bonding the two substrates, however, the sheet member44may be used as one of the two substrates. That is to say, the first flow path4may be formed of one substrate and the sheet member44.