Separation chip

Abstract

To provide a separation chip capable of suppressing reduction of a capture rate of to-be captured dielectric particles.SOLUTION: A separation chip 100 includes a substrate 101 and a plurality of electrode parts 12. The plurality of electrode portions 12 are disposed on one surface 1011 of the substrate 101, have at least tooth portions 1201, and extend in a first direction X. The plurality of electrode portions 12 are disposed adjacent to each other in a second direction Y intersecting the first direction X. A flow path 110 through which a liquid containing dielectric particles P1 flows in a flow direction D intersecting the first direction X is provided on one side of the plurality of electrodes 12. At least one electrode portion 12 is different from another electrode portion 12 in at least one of a cross-sectional shape along the second direction Y, dimensions of the cross-section along the second direction Y, and materials thereof.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a separation chip.

Background Art

[0002] Conventionally, a separation chip for separating specific cells from blood has been known (see, for example, Patent Document 1). Patent Document 1 describes a chip provided with a DEP (dielectrophoresis) unit that realizes separation and recovery of cells and the like by dielectrophoresis. The DEP unit includes a pair of comb-shaped electrodes provided on a flow path and facing each other. By applying an alternating voltage between the pair of electrodes, dielectrophoresis is generated. By appropriately adjusting the applied alternating voltage and frequency, desired cells such as CTCs are induced and separated.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, generally, when capturing cells or the like by dielectrophoretic force using comb-shaped electrodes, the applied alternating voltage and frequency are adjusted according to the type of cells to be captured, the medium around the cells, the electrode shape, and the like.

[0005] However, among a plurality of cells, there are variations in characteristics such as size and dielectric constant, so there are also variations in the dielectrophoretic force acting on the cells. For this reason, a part of the cells to be captured may not be captured, and the capture rate may decrease.

[0006] The present invention has been made in view of the above problems, and an object thereof is to provide a separation chip capable of suppressing a decrease in the capture rate of dielectric particles to be captured.

Means for Solving the Problem

[0007] The separation chip according to the first aspect of the present invention includes a substrate and a plurality of electrode portions. The plurality of electrode portions are arranged on one surface of the substrate, have at least electrodes, and extend in a first direction. The plurality of electrode portions are arranged adjacent to each other in a second direction intersecting the first direction. On one side of the plurality of electrode portions, a flow path is provided through which a liquid containing dielectric particles flows in a flow direction intersecting the first direction. At least one of the electrode portions and the other electrode portions differ in at least one of the cross-sectional shape along the second direction, the dimensions in the cross-section along the second direction, and the material.

[0008] In one aspect of the present invention, at least one of the electrodes and the other electrodes may differ in at least one of the cross-sectional shape along the second direction, the dimensions in the cross-section along the second direction, and the material.

[0009] In one aspect of the present invention, the at least one electrode and the other electrode may have different electrode widths in the cross-section along the second direction.

[0010] In one aspect of the present invention, the other electrode may be arranged on the downstream side in the flow direction compared to the at least one electrode. The electrode width of the other electrode may be smaller than the electrode width of the at least one electrode.

[0011] In one aspect of the present invention, the electrode portion may have an insulating layer arranged on one surface of the electrode. At least one of the insulating layers and the other insulating layers may differ in at least one of the cross-sectional shape along the second direction, the dimensions in the cross-section along the second direction, and the material.

[0012] In one aspect of the present invention, the insulating layer may have an opening connecting the electrode and the flow path. The widths of the openings in the cross-section along the second direction of the at least one insulating layer and the other insulating layer may be different.

[0013] In one aspect of the present invention, the other insulating layer may be disposed on the downstream side in the flow direction compared to the at least one insulating layer. The width of the opening along the second direction of the other insulating layer may be smaller than the width of the opening along the second direction of the at least one insulating layer.

[0014] In one aspect of the present invention, one surface of the electrode may have a first region and a second region different from the first region. The insulating layer may be disposed on the second region. The first region may be connected to the flow path through the opening. The first region may be located closer to the substrate side than the second region.

[0015] In one aspect of the present invention, ∇E between the electrodes adjacent to each other on the downstream side in the flow direction 2 may be larger than ∇E between the electrodes adjacent to each other on the upstream side in the flow direction. ∇E indicates the gradient of the electric field strength. 2

[0016] The separation chip according to the second aspect of the present invention includes a substrate and a plurality of electrode portions. The plurality of electrode portions are arranged on one surface of the substrate, have at least electrodes, and extend in a first direction. The plurality of electrode portions are arranged adjacent to each other in a second direction intersecting the first direction. On one side of the plurality of electrode portions, a flow path is provided through which a liquid containing dielectric particles flows in a flow direction intersecting the first direction. The distance between at least one pair of electrodes is different from the distance between other pairs of electrodes.

[0017] In one aspect of the present invention, the distance between the other electrodes on the downstream side in the flow direction may be smaller than the distance between the at least one pair of electrodes on the upstream side in the flow direction.

[0018] In one aspect of the present invention, the electrode portion may have an insulating layer disposed on one surface of the electrode. The insulating layer may have an opening connecting the electrode and the flow path. One surface of the electrode may have a first region and a second region different from the first region. The insulating layer may be disposed on the second region. The first region may be connected to the flow path through the opening. The first region may be located closer to the substrate side than the second region.

[0019] In one aspect of the present invention, ∇E between the electrodes adjacent to each other on the downstream side in the flow direction 2 may be larger than ∇E between the electrodes adjacent to each other on the upstream side in the flow direction. 2 ∇E indicates the gradient of the electric field strength.

[0020] The separation chip according to the third aspect of the present invention includes a substrate and a plurality of electrode portions. The plurality of electrode portions are disposed on one surface of the substrate, have at least electrodes, and extend in a first direction. The plurality of electrode portions are disposed adjacent to each other in a second direction intersecting the first direction. On one side of the plurality of electrode portions, a flow path is provided through which a liquid containing dielectric particles flows in a flow direction intersecting the first direction. ∇E between at least one of the electrodes 2 is different from ∇E between the other electrodes. 2 ∇E indicates the gradient of the electric field strength.

Advantages of the Invention

[0021] According to the present invention, it is possible to provide a separation chip capable of suppressing a decrease in the capture rate of dielectric particles to be captured.

Brief Description of the Drawings

[0022]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Mode for Carrying Out the Invention

[0023] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and the description thereof will not be repeated.

[0024] With reference to FIGS. 1 to 4, a dielectrophoresis device 1 including a separation chip 100 according to an embodiment of the present invention will be described. FIG. 1 is a plan view schematically showing the structure of a dielectrophoresis device 1 including a separation chip 100 according to an embodiment of the present invention.

[0025] As shown in FIG. 1, a dielectrophoresis device 1 according to an embodiment of the present invention includes a separation chip 100 and a voltage control device 500. The dielectrophoresis device 1 separates dielectric particles P1 from other particles P2 by applying a dielectrophoretic force to the dielectric particles P1 contained in a sample solution (sample liquid), and collects the dielectric particles P1. The sample solution is not particularly limited, but is, for example, blood. The dielectric particles P1 are not particularly limited, but are, for example, cells, proteins, nucleic acids, or microorganisms. The cells are, for example, cancer cells. Also, the sample solution may be seawater, physiological saline, pure water, or a chemical. The other particles P2 are, for example, dielectric particles of a different type from the dielectric particles P1, or non-dielectric particles. As an example, the sample solution is blood, the dielectric particles P1 are cancer cells, and the other particles P2 are white blood cells. Note that the sample solution is an example of the "liquid" of the present invention.

[0026] The separation chip 100 separates the dielectric particles P1 from other particles P2 by applying a dielectrophoretic force to the dielectric particles P1 contained in the sample solution, and collects the dielectric particles P1. The diameter of the dielectric particles P1 is, for example, several μm or more and several tens of μm or less.

[0027] The separation chip 100 includes a substrate 101, a flow path 110, and separation electrodes 120. The flow path 110 has a supply section 111, a separation flow path 112, and a collection section 113. The sample solution is introduced into the supply section 111. The supply section 111 has, for example, an opening. The supply section 111 is connected to the sample solution supply source by a tube, for example.

[0028] The separation flow path 112 connects the supply section 111 and the collection section 113. The sample solution introduced into the supply section 111 flows through the separation flow path 112 toward the collection section 113. The collection section 113 collects the sample solution that has passed through the separation flow path 112. The collection section 113 may have an opening, for example. The collection section 113 may supply the sample solution to the outside, for example. Note that in the present embodiment, as will be described later, the collection section 113 collects the sample solution from which the dielectric particles P1 have been separated (removed).

[0029] The separation chip 100 includes a flow path cover 105. The flow path cover 105 is disposed on the substrate 101. The flow path cover 105 has an area smaller than that of the substrate 101. That is, the flow path cover 105 is disposed on a part of the substrate 101. The flow path cover 105 has a recess that constitutes the flow path 110. The flow path 110 is constituted by the substrate 101 and the flow path cover 105.

[0030] The separation electrode 120 is formed of a conductive metal. In this embodiment, the metal is a concept including alloys. The separation electrode 120 is disposed at least in the separation flow path 112. In other words, the separation electrode 120 overlaps at least the separation flow path 112. The separation electrode 120 includes a first electrode 121 and a second electrode 122. The first electrode 121 and the second electrode 122 have, for example, a comb tooth shape facing each other. Note that the first electrode 121 and the second electrode 122 do not necessarily have a comb tooth shape.

[0031] The first electrode 121 has a plurality of tooth portions 1211, a first connection portion 1212, a second connection portion 1213, and a pad portion 1214. Note that the tooth portion 1211 is an example of the "electrode" of the present invention.

[0032] Each of the tooth portions 1211 extends in a substantially straight line. The plurality of tooth portions 1211 are arranged substantially parallel to each other. Also, the plurality of tooth portions 1211 extend in a first direction X that intersects the flow direction D in which the flow path 110 extends. The flow direction D is the direction in which the sample liquid flows. In this embodiment, the first direction X is substantially orthogonal to the flow direction D. That is, in this embodiment, the tooth portion 1211 is substantially orthogonal to the flow path 110. Also, the plurality of tooth portions 1211 are arranged at a predetermined interval in a second direction Y that intersects the first direction X. In this embodiment, the second direction Y is orthogonal to the first direction X. Hereinafter, the second direction Y may be referred to as the width direction. Note that in this embodiment, the second direction Y is parallel to the flow direction D.

[0033] The first connection part 1212 connects a plurality of tooth parts 1211 to each other. A comb tooth shape is formed by the plurality of tooth parts 1211 and the first connection part 1212. The plurality of tooth parts 1211 are arranged, for example, across the separation flow path 112 in a plan view. The first connection part 1212 is arranged outside the separation flow path 112 in a plan view. The plurality of tooth parts 1211 and the first connection part 1212 are covered by the flow path cover 105.

[0034] The second connection part 1213 connects the first connection part 1212 and the pad part 1214. At least a part of the second connection part 1213 is covered by the flow path cover 105. At least a part of the pad part 1214 is arranged outside the flow path cover 105 in a plan view. In the present embodiment, the second connection part 1213 is covered by the flow path cover 105. A part of the pad part 1214 is arranged outside the flow path cover 105 in a plan view. Thus, since at least a part of the pad part 1214 is not covered by the flow path cover 105, the pad part 1214 can be easily electrically connected to the voltage control device 500.

[0035] The second electrode 122 has a plurality of tooth parts 1221, a first connection part 1222, a second connection part 1223, and a pad part 1224. Note that the tooth part 1221 is an example of the "electrode" of the present invention.

[0036] Each of the tooth parts 1221 extends in a substantially straight line. The plurality of tooth parts 1221 are arranged substantially parallel to each other. Also, the plurality of tooth parts 1221 are arranged substantially parallel to the plurality of tooth parts 1211. The first connection part 1222 connects the plurality of tooth parts 1221 to each other. A comb tooth shape is formed by the plurality of tooth parts 1221 and the first connection part 1222. The plurality of tooth parts 1221 are arranged, for example, across the separation flow path 112 in a plan view. The first connection part 1222 is arranged outside the separation flow path 112 in a plan view. The plurality of tooth parts 1221 and the first connection part 1222 are covered by the flow path cover 105.

[0037] The second connection part 1223 connects the first connection part 1222 and the pad part 1224. At least a part of the second connection part 1223 is covered by the flow path cover 105. At least a part of the pad part 1224 is disposed outside the flow path cover 105 in a plan view. In the present embodiment, the second connection part 1223 is covered by the flow path cover 105. A part of the pad part 1224 is disposed outside the flow path cover 105 in a plan view. Thus, since at least a part of the pad part 1224 is not covered by the flow path cover 105, the pad part 1224 can be easily electrically connected to the voltage control device 500.

[0038] The voltage control device 500 is electrically connected to the pad part 1214 and the pad part 1224. The voltage control device 500 applies an alternating voltage corresponding to the type of the dielectric particles P1 to the first electrode 121 and the second electrode 122 via the pad part 1214 and the pad part 1224. The alternating voltage corresponding to the type of the dielectric particles P1 is, for example, a frequency that generates an electric field that specifically applies a dielectrophoretic force (attractive force) to the dielectric particles P1, and is a voltage having a magnitude that does not break the dielectric particles P1.

[0039] Specifically, the frequency of the alternating voltage is set so that a positive dielectrophoretic force (attractive force) acts on the dielectric particles P1 by the electric field between the first electrode 121 and the second electrode 122. Therefore, a positive dielectrophoretic force acts on the dielectric particles P1, and the dielectric particles P1 are attracted to the tooth parts 1211 and 1221. On the other hand, the frequency of the alternating voltage is set so that no dielectrophoretic force acts on the other particles P2, or hardly acts on the other particles P2. Therefore, the other particles P2 pass through the separation flow path 112 and are collected in the collection part 113. Hereinafter, the tooth parts 1211 and 1221 may be described as the tooth part 1201. Note that the tooth part 1201 is an example of the "electrode" of the present invention.

[0040] Continuing to refer to FIG. 1, the voltage control device 500 will be described. The voltage control device 500 includes a power supply part 510 and a control part 520.

[0041] The control unit 520 controls the power supply unit 510. The control unit 520 includes, for example, a processor and a storage device. The processor is, for example, a CPU (Central Processing Unit) or an MPU (Micro Processing Unit). The storage device stores data and computer programs. The storage device includes a main storage device such as a semiconductor memory and an auxiliary storage device such as a semiconductor memory, a solid state drive, and / or a hard disk drive. The storage device may include a removable medium. The storage device corresponds to an example of a non-transitory computer-readable storage medium.

[0042] The power supply unit 510 generates an alternating voltage corresponding to the dielectric particles P1 to be separated. Then, the power supply unit 510 applies the alternating voltage to the first electrode 121 and the second electrode 122 via the pad unit 1214 and the pad unit 1224. The power supply unit 510 is, for example, a signal generator such as a function generator.

[0043] By applying an alternating voltage corresponding to the dielectric particles P1 to the first electrode 121 and the second electrode 122 by the power supply unit 510, a dielectrophoretic force (attractive force) acts on the dielectric particles P1. As a result, the dielectric particles P1 are attracted to the tooth portions 1201 (tooth portions 1211 and tooth portions 1221), and the dielectric particles P1 are separated from the other particles P2. In the present embodiment, the dielectric particles P1 are captured by the tooth portions 1201, and the other particles P2 pass through the separation channel 112 and are collected by the collection unit 113.

[0044] Note that the voltage control device 500 may have a function of measuring the electrical characteristics (such as impedance) between the first electrode 121 and the second electrode 122. Further, the voltage control device 500 may be configured by, for example, a source measure unit.

[0045] Next, with reference to FIG. 2, the structure of the separation chip 100 will be further described. FIG. 2 is an enlarged cross-sectional view schematically showing a cross-sectional structure around the tooth portion 1201 of the separation chip 100 of the present embodiment.

[0046] As shown in FIG. 2, the separation chip 100 includes an insulating film 103 in addition to a substrate 101, a separation electrode 120, and a flow path cover 105. The substrate 101 is, for example, a glass substrate. The material of the substrate 101 is, for example, quartz glass. However, the material of the substrate 101 is not limited to quartz glass. The substrate 101 has, for example, a substantially rectangular flat plate shape. However, the shape of the substrate 101 is not limited to the flat plate shape.

[0047] The separation electrode 120 is disposed on one surface 1011 of the substrate 101. The material of the separation electrode 120 is, for example, a metal such as aluminum, copper, and / or titanium. However, the material of the separation electrode 120 may be a metal other than aluminum, copper, and / or titanium. For example, the material of the separation electrode 120 may be a metal such as indium, tin, molybdenum, silver, chromium, tantalum, and / or silicon. Further, the material of the separation electrode 120 may be other than a metal, and may include, for example, an oxide such as a metal oxide, or a semiconductor. Further, the surface of the separation electrode 120 may be oxidized. Further, the separation electrode 120 may be formed of, for example, ITO (Indium Tin Oxide). In addition, as long as the separation electrode 120 has conductivity, the material of the separation electrode 120 is not particularly limited.

[0048] The separation electrode 120 has a substantially rectangular cross-sectional shape. The separation electrode 120 has one surface 1205 and a pair of side surfaces 1206. One surface 1205 is a surface on one side (opposite side to the substrate 101) of the separation electrode 120. In the present embodiment, one surface 1205 of the separation electrode 120 is a surface that can be seen when the separation electrode 120 is viewed from the flow path 110 side. Further, in the present embodiment, one surface 1205 of the separation electrode 120 is a surface substantially parallel to one surface 1011 of the substrate 101.

[0049] The pair of side surfaces 1206 are connected to one surface 1205. The pair of side surfaces 1206 extend from the end portion of one surface 1205 in the second direction Y toward the substrate 101.

[0050] The insulating film 103 covers at least a part of one surface 1205 of the separation electrode 120. In the present embodiment, the insulating film 103 covers the entire surface of at least one surface 1205 of the tooth portion 1201. Further, the insulating film 103 covers a portion of one surface 1011 of the substrate 101 where the separation electrode 120 is not disposed and at least a part of the separation electrode 120. Note that the insulating film 103 does not cover at least the portion of the pad portions 1214 and 1224 that is connected to the voltage control device 500. Also, the insulating film 103 covers at least the side surface 1206 of the tooth portion 1201.

[0051] The insulating film 103 has insulating properties. The material of the insulating film 103 is, for example, an oxide film such as a silicon oxide film, a nitride film such as a silicon nitride film, or a resin. In the present embodiment, the insulating film 103 is a silicon oxide film. Also, the thickness and material of the insulating film 103 affect the electric field formed by the separation electrode 120. That is, it is also possible to control the electric field formed by the tooth portion 1201 of the separation electrode 120 according to the thickness and material of the insulating film 103. Note that the insulating film 103 also functions as a protective film that suppresses an electrochemical reaction from occurring between the tooth portion 1201 of the separation electrode 120 and the sample solution.

[0052] In the present embodiment, the insulating film 103 has a plurality of cover portions 1031. The cover portion 1031 is a portion of the insulating film 103 that is disposed on one surface 1205 of the tooth portion 1201. Note that the cover portion 1031 is an example of the "insulating layer" of the present invention.

[0053] In the present embodiment, the tooth portion 1201 and the cover portion 1031 constitute the electrode portion 12. In other words, the separation chip 100 includes a plurality of electrode portions 12, and each electrode portion 12 has a tooth portion 1201 and a cover portion 1031. Therefore, the electrode portion 12 extends along the first direction X. The plurality of electrode portions 12 are disposed adjacent to each other in the second direction Y. And a flow path 110 is provided on one side of the plurality of electrode portions 12.

[0054] The thickness of the tooth portion 1201 of the electrode portion 12 is not particularly limited. The tooth portion 1201 has a thickness of, for example, not less than several nm and not more than several μm. The width of the tooth portion 1201 is not particularly limited. The tooth portion 1201 has a width of, for example, not less than several tens of μm and not more than several hundreds of μm. Further, the thickness of the cover portion 1031 of the electrode portion 12 is not particularly limited. The cover portion 1031 has a thickness of, for example, not less than several hundreds of nm and not more than several μm. Also, the distance between adjacent tooth portions 1201 is not particularly limited. The distance between adjacent tooth portions 1201 is, for example, not less than ten μm and not more than one hundred μm. Note that the detailed structure of the electrode portion 12 will be described later.

[0055] The flow path cover 105 is disposed, for example, on one surface 1033 of the insulating film 103. A part of the flow path cover 105 may be disposed on one surface 1011 of the substrate 101. And the flow path cover 105 covers one side (the side opposite to the substrate 101) of the separation electrode 120 and the insulating film 103. Also, the flow path cover 105 constitutes the flow path 110. Specifically, the flow path cover 105 includes side walls 1051 (see FIG. 1) and a ceiling 1052. The side walls 1051 and the ceiling 1052 constitute the flow path 110 through which the sample liquid flows. The side walls 1051 surround at least a part of the separation electrode 120 in a plan view.

[0056] The material of the flow path cover 105 is not particularly limited, but is, for example, a silicone-based resin. In the present embodiment, the material of the flow path cover 105 is PDMS (polydimethylsiloxane). When the flow path cover 105 is formed of PDMS, by performing plasma treatment on the surfaces of the flow path cover 105, the insulating film 103, and the substrate 101, the flow path cover 105 is firmly adhered to the surfaces of the insulating film 103 and the substrate 101.

[0057] Next, with reference to FIGS. 2 and 3, the detailed structure of the electrode portion 12 will be described. FIG. 3 is an enlarged cross-sectional view schematically showing the cross-sectional structure around the tooth portion 1201 of the separation chip 100 of the present embodiment.

[0058] As shown in FIGS. 2 and 3, at least one electrode portion 12 and the other electrode portions 12 differ in at least one of the cross-sectional shape along the second direction Y, the dimensions in the cross-section along the second direction Y, and the material. In the present embodiment, at least one electrode portion 12 and the other electrode portions 12 differ in the dimensions in the cross-section along the second direction Y.

[0059] Also, at least one tooth portion 1201 and the other tooth portions 1201 differ in at least one of the cross-sectional shape along the second direction Y, the dimensions in the cross-section along the second direction Y, and the material. In the present embodiment, at least one tooth portion 1201 and the other tooth portions 1201 differ in the dimensions in the cross-section along the second direction Y.

[0060] Also, at least one tooth portion 1201 and the other tooth portions 1201 differ in the electrode width W120 in the cross-section along the second direction Y. In the present embodiment, the other tooth portions 1201 are arranged on the downstream side in the flow direction D compared to at least one tooth portion 1201.

[0061] Hereinafter, a specific description will be given. FIG. 2 shows, for example, the structure around the electrode portion 12 arranged on the upstream side (the left side in FIG. 1) in the flow direction D among the plurality of electrode portions 12. FIG. 3 shows, for example, the structure around the electrode portion 12 arranged on the downstream side (the right side in FIG. 1) in the flow direction D among the plurality of electrode portions 12. And at least one tooth portion 1201 (here, the two tooth portions 1201 shown in FIG. 2) and the other tooth portions 1201 (here, the two tooth portions 1201 shown in FIG. 3) differ in the electrode width W120 along the second direction Y. In the present embodiment, the electrode width W120 of the other tooth portions 1201 is smaller than the electrode width W120 of at least one tooth portion 1201.

[0062] In this embodiment, at least one cover part 1031 (here, the two cover parts 1031 shown in FIG. 2) and the other cover parts 1031 (here, the two cover parts 1031 shown in FIG. 3) are different in at least one of the cross-sectional shape along the second direction Y, the dimensions in the cross-section along the second direction Y, and the material. In this embodiment, at least one cover part 1031 and the other cover parts 1031 are different in the dimensions in the cross-section along the second direction Y.

[0063] Also, at least one cover part 1031 (here, the two cover parts 1031 shown in FIG. 2) and the other cover parts 1031 (here, the two cover parts 1031 shown in FIG. 3) are different in the width along the second direction Y. In this embodiment, the width W1031 of the other cover parts 1031 is smaller than the width W1031 of at least one cover part 1031. Note that in this embodiment, the width W1031 is the same size as the electrode width W120. Also, in this embodiment, the distance L120 between all electrodes (between adjacent tooth parts 1201) is the same.

[0064] Next, the dielectrophoretic force (attractive force) acting on the dielectric particles P1 due to the electric field between the first electrode 121 and the second electrode 122 will be described. The dielectrophoretic force is represented by the following general formula (1).

[0065] (Equation 1) F = 2πr 3 ε m Re[K(ω)]∇E 2 ···(1)

[0066] Here, F indicates the dielectrophoretic force. r indicates the radius of the dielectric particles. ε m indicates the real part of the dielectric constant of the surrounding medium. ω indicates the angular frequency. K(ω) indicates the Clausius-Mossotti function. E indicates the electric field strength. Note that ∇E indicates the gradient of the electric field strength.

[0067] The πr in the above (1) 3 ε mRe[K(ω)] is determined by the dielectric particles P1 and the medium. On the other hand, ∇E 2 is determined based on the electrode portion 12. Therefore, as described above, at least one electrode portion 12 and the other electrode portion 12 have at least one of a cross-sectional shape along the second direction Y, dimensions in a cross-section along the second direction Y, and a material different from each other, so that ∇E 2 between at least one pair of electrodes (between adjacent tooth portions 1201) is 2 different from ∇E

[0068] between the other electrodes (between adjacent tooth portions 1201). 2 And in the present embodiment, ∇E 2 between adjacent tooth portions 1201 on the downstream side in the flow direction D is

[0069] larger than ∇E

[0070] Next, with reference to FIG. 4, the capture of the dielectric particles P1 by the separation chip 100 of the present embodiment will be described. FIG. 4 is a plan view schematically showing the structure around the tooth portion 1201 of the separation chip 100. In FIG. 4, for easy understanding, the tooth portion 1201 is hatched. Also, in FIG. 4, for easy understanding, the flow path cover 105, the insulating film 103, etc. are omitted. 3 ε m The dielectric particles P1 with a relatively large πr 2 Re[K(ω)] in (1) above are defined as dielectric particles P11, and the relatively small dielectric particles P1 are defined as dielectric particles P12. Also, ∇E 2 between the electrodes (between adjacent tooth portions 1201) on the downstream side is assumed to be larger than ∇E

[0071] As shown in FIG. 4, when a liquid containing dielectric particles P11 and P12 flows through the flow path 110, the dielectric particle P11 is captured by the upstream tooth portion 1201. On the other hand, the dielectric particle P12 is not captured by the upstream tooth portion 1201 and passes through the upstream tooth portion 1201. Then, the dielectric particle P12 is captured by the downstream tooth portion 1201.

[0072] Here, an example of setting the magnitude of ∇E 2 to two levels has been described, but the present invention is not limited to this. The separation chip 100 may be configured so that the magnitude of ∇E 2 can be set to three or more levels. That is, for example, the electrode width W120 may be set to three or more levels.

[0073] In the present embodiment, as described above, at least one electrode portion 12 and the other electrode portions 12 are different in at least one of the cross-sectional shape along the second direction Y, the dimensions in the cross-section along the second direction Y, and the material. Therefore, ∇E 2 between at least one pair of electrodes is different from ∇E 2 between the other pairs of electrodes. For this reason, the magnitude of ∇E 2 generated between a plurality of electrodes (between adjacent tooth portions 1201) can be varied. Thus, even if there are variations in characteristics such as size and dielectric constant among a plurality of dielectric particles P1, and among the plurality of dielectric particles P1, there is a dielectric particle P12 with a relatively small πr 3 ε m Re[K(ω)] in the above formula (1), the dielectric particle P12 can be captured by the tooth portion 1201 where a relatively large ∇E 2 is generated. Therefore, it is possible to suppress a decrease in the capture rate of the dielectric particles P1 to be captured.

[0074] Also, as described above, at least one tooth portion 1201 and the other tooth portions 1201 are different in at least one of the cross-sectional shape along the second direction Y, the dimensions in the cross-section along the second direction Y, and the material. Therefore, between at least one electrode portion 12 and the other electrode portions 12, it is possible to easily vary at least one of the cross-sectional shape along the second direction Y, the dimensions in the cross-section along the second direction Y, and the material.

[0075] Also, as described above, at least one tooth portion 1201 and the other tooth portions 1201 have different electrode widths W120 in the cross-section along the second direction Y. Therefore, ∇E generated between at least one pair of electrodes 2 and ∇E generated between the other pairs of electrodes 2 can be easily made different.

[0076] Also, as described above, the other tooth portions 1201 are arranged on the downstream side in the flow direction D compared to at least one tooth portion 1201, and the electrode width W120 of the other tooth portions 1201 is smaller than the electrode width W120 of at least one tooth portion 1201. Therefore, ∇E generated on the downstream side in the flow direction D 2 can be made larger than ∇E 2 generated on the upstream side in the flow direction D. Thus, it is possible to easily capture the dielectric particles P1 that were not captured on the upstream side in the flow direction D on the downstream side in the flow direction D.

[0077] Also, ∇E generated on the upstream side in the flow direction D 2 is smaller than ∇E 2 generated on the downstream side in the flow direction D, so the dielectric particles P11 are captured by the upstream tooth portions 1201. Thus, it is possible to suppress the dielectric particles P11 from reaching the tooth portions 1201 where ∇E 2 is relatively large. That is, it is possible to suppress the dielectrophoretic force from becoming too large due to the relatively large "πr 3 ε m Re[K(ω)]" and the relatively large "∇E 2 ". Thus, for example, it is possible to suppress the dielectric particles P11 from being crushed or the dielectric particles P11 from adhering to the tooth portions 1201.

[0078] (First Modified Example) Next, with reference to FIGS. 2 and 5, the separation chip 100 according to the first modified example of the present invention will be described. FIG. 5 is an enlarged cross-sectional view schematically showing the cross-sectional structure around the tooth portion 1201 of the separation chip 100 according to the first modified example of the present invention. In the first modified example, different from the above-described embodiment, an example in which the distance between electrodes is different will be described.

[0079] As shown in FIGS. 2 and 5, in the separation chip 100 of the first modified example, different from the above-described embodiment, all the electrode portions 12 have the same cross-sectional shape along the second direction Y, dimensions in the cross-section along the second direction Y, and material. Specifically, the tooth portions 1201 of all the electrode portions 12 have the same cross-sectional shape along the second direction Y, dimensions in the cross-section along the second direction Y, and material. Further, the cover portions 1031 of all the electrode portions 12 have the same cross-sectional shape along the second direction Y, dimensions in the cross-section along the second direction Y, and material.

[0080] Here, in the first modified example, the distance L120 between at least one pair of electrodes (here, between the two tooth portions 1201 shown in FIG. 2) is different from the distance L120 between other pairs of electrodes (here, between the two tooth portions 1201 shown in FIG. 5).

[0081] Further, in the first modified example, the distance L120 between other pairs of electrodes on the downstream side in the flow direction D is smaller than the distance L120 between at least one pair of electrodes on the upstream side in the flow direction D. In other words, the distance L120 between adjacent tooth portions 1201 on the downstream side in the flow direction D is smaller than the distance L120 between adjacent tooth portions 1201 on the upstream side in the flow direction D.

[0082] In the first modified example, similar to the above-described embodiment, ∇E between at least one pair of electrodes 2 is different from ∇E between other pairs of electrodes 2 Also, in the first modified example, ∇E between adjacent tooth portions 1201 on the downstream side in the flow direction D 2is larger than ∇E between the tooth portions 1201 adjacent to each other on the upstream side in the flow direction D. 2 is larger.

[0083] In the first modification, as described above, the distance L120 between at least one pair of electrodes is different from the distance L120 between the other electrodes. Therefore, similar to the above embodiment, ∇E generated between the plurality of electrodes 2 can be made to vary in magnitude. Thus, it is possible to suppress a decrease in the capture rate of the dielectric particles P1 to be captured.

[0084] In the first modification, as described above, the distance L120 between the other electrodes on the downstream side in the flow direction D is smaller than the distance L120 between at least one pair of electrodes on the upstream side in the flow direction D. Therefore, ∇E generated on the downstream side in the flow direction D 2 can be made larger than ∇E 2 generated on the upstream side in the flow direction D. Thus, it is possible to capture the dielectric particles P1 that were not captured on the upstream side in the flow direction D on the downstream side in the flow direction D.

[0085] Also, since ∇E 2 generated on the upstream side in the flow direction D is smaller than ∇E 2 generated on the downstream side in the flow direction D, the dielectric particles P11 are captured by the tooth portions 1201 on the upstream side. Thus, it is possible to suppress the dielectric particles P11 from reaching the tooth portions 1201 where ∇E 2 is relatively large. Thus, for example, it is possible to suppress the dielectric particles P11 from being crushed or the dielectric particles P11 from adhering to the tooth portions 1201.

[0086] Other configurations and effects of the first modification are the same as those of the above embodiment.

[0087] (Second Modification) Next, referring to FIG. 6, the separation chip 100 according to the second modification of the present invention will be described. FIG. 6 is an enlarged cross-sectional view schematically showing the structure around the tooth portion 1201 of the separation chip 100 according to the second modification of the present invention. In the second modification, different from the above-described embodiment and the first example, an example in which an opening 1032 is formed in the cover portion 1031 of the insulating film 103 will be described.

[0088] As shown in FIG. 6, in the second modification, one surface 1205 of the tooth portion 1201 has a first region 12051 and a second region 12052 different from the first region 12051. Specifically, one surface 1205 has a first region 12051 located at the center in the width direction and a pair of second regions 12052 arranged outside the first region 12051 in the width direction.

[0089] Note that, in the second modification, different from the above-described embodiment and the first example, the distance L120 between all the electrodes is the same.

[0090] The insulating film 103 covers at least a part of one surface 1205 of the tooth portion 1201. In the second modification, the thickness of the insulating film 103 on the first region 12051 of the tooth portion 1201 is smaller than the thickness of the insulating film 103 on the second region 12052 of the tooth portion 1201. In the second modification, the thickness of the insulating film 103 on the first region 12051 of the tooth portion 1201 is zero. Note that the thickness of the insulating film 103 on the first region 12051 may not be zero.

[0091] Specifically, the insulating film 103 has an opening 1032 that connects the first region 12051 of the tooth portion 1201 and the flow path 110. That is, in the second modification, the insulating film 103 is not formed on the first region 12051. The opening 1032 is located on the first region 12051 and penetrates the insulating film 103.

[0092] In the second modification, similar to the above-described embodiment and the first modification, at least one cover portion 1031 and the other cover portion 1031 differ in at least one of the cross-sectional shape along the second direction Y, the dimensions in the cross-section along the second direction Y, and the material. Also, in the second modification, at least one cover portion 1031 and the other cover portion 1031 differ in the width W1032 of the opening 1032 in the cross-section along the second direction Y.

[0093] Further, in the second modification, the width W1032 of the opening 1032 is the same size as the width W121 of the first region 12051. Also, the widths of all the second regions 12052 are the same. That is, the width of the tooth portion 1201 on the downstream side is smaller than the width of the tooth portion 1201 on the upstream side.

[0094] Other configurations of the second modification are the same as those of the above-described embodiment and the first modification.

[0095] In the second modification, as described above, at least one cover portion 1031 and the other cover portion 1031 differ in at least one of the cross-sectional shape along the second direction Y, the dimensions in the cross-section along the second direction Y, and the material. Therefore, it is possible to easily make at least one of the cross-sectional shape along the second direction Y, the dimensions in the cross-section along the second direction Y, and the material different between at least one electrode portion 12 and the other electrode portion 12.

[0096] In the second modification, as described above, at least one cover portion 1031 and the other cover portion 1031 differ in the width W1032 of the opening 1032 in the cross-section along the second direction Y. Therefore, ∇E generated between at least one pair of electrodes 2 and ∇E generated between the other pair of electrodes 2 can be easily made different.

[0097] Other effects of the second modification are the same as those of the above-described embodiment and the first modification.

[0098] (Third Modification) Next, referring to FIG. 7, the separation chip 100 according to the third modification of the present invention will be described. FIG. 7 is an enlarged cross-sectional view schematically showing the structure around the tooth portion 1201 of the separation chip 100 according to the third modification of the present invention. In the third modification, different from the above-described embodiment, the first embodiment, and the second modification, an example in which the tooth portion 1201 has a substantially concave shape in a cross-sectional view will be described.

[0099] As shown in FIG. 7, in the third modification, similar to the second modification, one surface 1205 of the tooth portion 1201 has a first region 12051 and a second region 12052 different from the first region 12051.

[0100] Here, in the third modification, a step 12053 is formed on one surface 1205 of the tooth portion 1201. Also, in the third modification, the electrode portion 12 and the tooth portion 1201 have a concave shape in a cross-sectional view. Specifically, the pair of second regions 12052 respectively extend inward in the width direction from the pair of side surfaces 1206. The first region 12051 is disposed substantially parallel to the second regions 12052 between the pair of second regions 12052. The first region 12051 is disposed closer to the substrate 101 than the pair of second regions 12052. The tooth portion 1201 has a pair of connection surfaces 1251, and the pair of connection surfaces 1251 connect the pair of second regions 12052 and the first region 12051. And a recess 1260 is formed in the tooth portion 1201 by the first region 12051 and the pair of connection surfaces 1251.

[0101] The insulating film 103 covers at least a part of one surface 1205 of the tooth portion 1201, similar to the second modification. Also, the thickness of the insulating film 103 on the first region 12051 of the tooth portion 1201 is smaller than the thickness of the insulating film 103 on the second region 12052 of the tooth portion 1201. In the third modification, the thickness of the insulating film 103 on the first region 12051 of the tooth portion 1201 is zero.

[0102] Specifically, similar to the second modification example, the insulating film 103 has an opening 1032 that connects the first region 12051 of the tooth portion 1201 and the flow path 110. That is, in the third modification example, the insulating film 103 is not formed on the first region 12051. The opening 1032 is located on the first region 12051 and penetrates the insulating film 103.

[0103] Also, the insulating film 103 is not formed on at least a part of the connection surface 1251. That is, at least a part of the connection surface 1251 is connected to the flow path 110 without passing through the insulating film 103. In the third modification example, the insulating film 103 is not formed on the connection surface 1251.

[0104] In the third modification example, similar to the above-described embodiment, the first modification example, and the second modification example, at least one electrode portion 12 and the other electrode portions 12 differ in at least one of the cross-sectional shape along the second direction Y, the dimensions in the cross-section along the second direction Y, and the material. Also, at least one electrode portion 12 and the other electrode portions 12 have different dimensions in the cross-section along the second direction Y.

[0105] Also, at least one tooth portion 1201 and the other tooth portions 1201 differ in at least one of the cross-sectional shape along the second direction Y, the dimensions in the cross-section along the second direction Y, and the material. In the third modification example, at least one tooth portion 1201 and the other tooth portions 1201 have different dimensions in the cross-section along the second direction Y.

[0106] Also, at least one tooth portion 1201 and the other tooth portions 1201 have different electrode widths W120 in the cross-section along the second direction Y. In the third modification example, the other tooth portions 1201 are arranged on the downstream side in the flow direction D compared to at least one tooth portion 1201.

[0107] Here, in the third modification example, the width W121 along the second direction Y of the first region 12051 of at least one tooth portion 1201 is different from that of the first region 12051 of the other tooth portions 1201. In the third modification example, the width W121 of the first region 12051 of the other tooth portions 1201 on the downstream side in the flow direction D is smaller than the width W121 of the first region 12051 of at least one tooth portion 1201 on the upstream side in the flow direction D. Also, the width W122 in the cross-section along the second direction Y of the second region 12052 of all the tooth portions 1201 is the same. Therefore, the electrode width W120 of the other tooth portions 1201 on the downstream side in the flow direction D is smaller than the electrode width W120 of at least one tooth portion 1201 on the upstream side in the flow direction D. Note that in the third modification example, the width 121 of the first region 12051 is the same size as the width W1032 of the opening 1032.

[0108] Other configurations of the third modification example are the same as those of the above-described embodiment, the first modification example, and the second modification example.

[0109] In the third modification example, as described above, the width W121 of the first region 12051 of the other tooth portions 1201 on the downstream side in the flow direction D is smaller than the width W121 of the first region 12051 of at least one tooth portion 1201 on the upstream side in the flow direction D. In other words, the width W1032 of the opening 1032 along the second direction Y of the other cover portion 1031 is smaller than the width W1032 of the opening 1032 along the second direction Y of at least one cover portion 1031. Therefore, ∇E generated on the downstream side in the flow direction D 2 can be made easily larger than ∇E generated on the upstream side in the flow direction D. 2 Thus, it is possible to easily capture the dielectric particles P1 that were not captured on the upstream side in the flow direction D on the downstream side in the flow direction D.

[0110] Also, since ∇E generated on the upstream side in the flow direction D 2 is smaller than ∇E generated on the downstream side in the flow direction D 2 the dielectric particles P11 are captured by the tooth portions 1201 on the upstream side. Thus, the dielectric particles P11 are ∇E 2It is possible to suppress reaching the relatively large tooth portion 1201. Therefore, for example, it is possible to suppress the dielectric particles P11 from being crushed or the dielectric particles P11 from adhering to the tooth portion 1201.

[0111] In the third modification, as described above, the first region 12051 is connected to the flow path 110 via the opening 1032, and the first region 12051 is located closer to the substrate 101 side than the second region 12052. Therefore, the electrode portion 12 and the tooth portion 1201 can be formed in a concave shape, and the effects described below can be obtained.

[0112] Next, with reference to FIGS. 8 and 9, the effects of making the electrode portion 12 and the tooth portion 1201 of the separation chip 100 of the third modification concave will be described. Here, the effects of the separation chip 100 of the third modification will be described in comparison with the separation chip 100 of the embodiment shown in FIGS. 1 to 4. FIG. 8 is a diagram for explaining the effects of the separation chip 100 of the third modification, and is an enlarged cross-sectional view schematically showing the structure around the tooth portion 1201 of the separation chip 100 of the embodiment shown in FIGS. 1 to 4. FIG. 9 is an enlarged cross-sectional view schematically showing the structure around the tooth portion 1201 of the separation chip 100 of the third modification. Note that the electric field is strong at the corner of the electrode, and the gradient of the electric field strength is large. For this reason, in FIGS. 8 and 9, in order to facilitate understanding of the invention, the image of the region where the force (attractive force) attracting the dielectric particles is strong is shown by a broken line.

[0113] First, with reference to FIG. 8, the separation chip 100 of the above embodiment will be described. As shown in FIG. 8, in the separation chip 100 of the above embodiment, the tooth portion 1201 has a substantially rectangular shape in cross section. That is, no step is formed on one surface 1205 of the tooth portion 1201. Further, the insulating film 103 has a substantially uniform thickness on one surface 1205 of the tooth portion 1201. Further, no opening 1032 is formed in the insulating film 103.

[0114] In the separation chip 100 of the above embodiment, ∇E between two tooth portions 1201 2 is ∇E around the adjacent corner portions 1127 of the two tooth portions 1201 2It is estimated that it becomes the largest. For this reason, the dielectric particle P1 is attracted to the corner portion 1127. Therefore, the dielectric particle P1 is attracted to the width direction end portion of the tooth portion 1201. In the separation chip 100 of the above embodiment, even if the frequency and voltage are changed, the position where the dielectric particle P1 is attracted does not change.

[0115] On the other hand, as shown in FIG. 9, in the separation chip 100 of the third modification, the thickness of the insulating film 103 on the first region 12051 of the tooth portion 1201 is smaller than the thickness of the insulating film 103 on the second region 12052 of the tooth portion 1201. Therefore, by adjusting the voltage value and frequency applied between the tooth portions 1201, ∇E 2 at the periphery of the end of the adjacent first region 12051 (here, the recess 1260) can be maximized. Thus, the dielectric particle P1 is attracted to the first region 12051 (here, the recess 1260) of the tooth portion 1201. Therefore, the dielectric particle P1 is attracted to the center in the width direction of the tooth portion 1201.

[0116] Specifically, as can also be understood from the fact that the term of ∇E 2 is included in the above formula (1), the dielectrophoretic force occurs in a non-uniform region of the alternating current electric field. The non-uniform region of the alternating current electric field indicates a region where the interval between the electric lines of force changes. In the separation chip 100 shown in FIG. 8, a non-uniform electric field occurs around the corner portion 1127 located at the width direction end portion of the tooth portion 1201. For this reason, the location that attracts the dielectric particle P1 is uniquely determined at the corner portion 1127. Therefore, for example, even if the frequency or the like is changed, the position that attracts the dielectric particle P1 cannot be changed.

[0117] On the other hand, in the separation chip 100 of the third modification shown in FIG. 9, by making the thickness of the insulating film 103 on the first region 12051 of the tooth portion 1201 smaller than the thickness of the insulating film 103 on the second region 12052 of the tooth portion 1201, a non-uniform region of the alternating current electric field changes relatively with respect to the separation chip 100 shown in FIG. 8 on one surface 1205 of the tooth portion 1201. For example, by arranging the first region 12051 at an arbitrary position, the position where the dielectric particles P1 are attracted can be set at an arbitrary position. In the third modification, the position where the dielectric particles P1 are attracted can be set at the center in the width direction of the tooth portion 1201.

[0118] Further, in the separation chip 100 of the third modification, by forming a step 12053 and / or a recess 1260 on one surface 1205 of the tooth portion 1201, the alternating current electric field can be made more non-uniform around a predetermined position on one surface 1205 of the tooth portion 1201. That is, the change rate (gradient of the electric field strength) of the electric field strength around a predetermined position on one surface 1205 of the tooth portion 1201 can be made larger. For this reason, the dielectrophoretic force can be made stronger.

[0119] Other effects of the third modification are the same as those of the above-described embodiment, the first modification, and the second modification.

[0120] (Fourth Modification) Next, with reference to FIG. 10, the separation chip 100 according to the fourth modification of the present invention will be described. FIG. 10 is a plan view schematically showing the structure of the separation chip 100 according to the fourth modification of the present invention. In the fourth modification, different from the above-described embodiment, an example will be described in which the tooth portion 1211 and the tooth portion 1221 of the separation electrode 120 are inclined with respect to the flow path 110.

[0121] As shown in FIG. 10, in the separation chip 100 of the fourth modification, the plurality of tooth portions 1211 of the first electrode 121 and the plurality of tooth portions 1221 of the second electrode 122 extend in a first direction X that intersects the flow direction D in which the flow path 110 extends. In the fourth modification, unlike the above-described embodiment, the first direction X is inclined with respect to the flow direction D in which the sample liquid flows. That is, in the fourth modification, the tooth portions 1211 and 1221 are inclined with respect to the flow path 110. By configuring in this way, for example, by applying an alternating voltage of a specific frequency between the first electrode 121 and the second electrode 122, the dielectric particles P1 can be moved along the tooth portions 1211 and 1221. Therefore, the dielectric particles P1 can be easily separated from the other particles P2. This will be described in detail below.

[0122] In the fourth modification, the collection portion 113 of the flow path 110 has a first collection portion 1131 and a second collection portion 1132. The first collection portion 1131 collects the dielectric particles P1. The second collection portion 1132 collects the other particles P2. The flow path 110 further has a first connection flow path 1141 and a second connection flow path 1142. The first connection flow path 1141 connects the downstream portion of the separation flow path 112 and the first collection portion 1131. The second connection flow path 1142 connects the downstream portion of the separation flow path 112 and the second collection portion 1132.

[0123] In the separation chip 100 of the fourth modification, by applying an alternating voltage of a specific frequency between the first electrode 121 and the second electrode 122, a dielectrophoretic force acts on the dielectric particles P1 passing through the separation flow path 112. As a result, the dielectric particles P1 move along the tooth portions 1211 and 1221. In the fourth modification, the dielectric particles P1 move along the tooth portions 1211 and 1221 toward the first connection portion 1212 side.

[0124] Then, the dielectric particles P1 pass through the first connection flow path 1141 and are collected in the first collection portion 1131. On the other hand, the other particles P2 travel straight through the separation flow path 112, pass through the second connection flow path 1142, and are collected in the second collection portion 1132.

[0125] The other structures and effects of the fourth modification example are the same as those of the above-described embodiment and the first to third modification examples.

[0126] (Fifth Modification Example) Next, with reference to FIG. 11, the separation chip 100 according to the fifth modification example of the present invention will be described. FIG. 11 is a plan view schematically showing the structure of the separation chip 100 according to the fifth modification example of the present invention. In the fifth modification example, different from the above-described embodiment, an example in which the separation chip 100 includes, for example, HDF (Hydrodynamic filtration) 200 will be described.

[0127] As shown in FIG. 11, in the fifth modification example, the separation chip 100 further includes HDF 200. HDF 200 is disposed upstream of the separation electrode 120. HDF 200 has a function as a hydrodynamic filter. For example, HDF 200 is a microchannel for the purpose of separating and / or concentrating fine particles. HDF 200 has a plurality of branch channels 201 branching from the separation channel 112. The HDF 200 is constituted by the plurality of branch channels 201 and a part of the separation channel 112. The plurality of branch channels 201 are arranged, for example, so as to extend perpendicular to the separation channel 112. Also, the plurality of branch channels 201 are arranged, for example, at substantially equal pitches along the extending direction of the separation channel 112.

[0128] The liquid flowing through the separation channel 112 flows into the plurality of branch channels 201. Also, a part of the particles contained in the liquid flowing through the separation channel 112 flows into the plurality of branch channels 201. Particles with a smaller particle size are more likely to flow into the branch channel 201, and particles with a larger particle size are less likely to flow into the branch channel 201. That is, HDF 200 separates relatively small particles from the liquid flowing through the separation channel 112. In the fifth modification example, the dielectric particles P1 do not flow into the branch channel 201 of HDF 200 and substantially go straight through the separation channel 112.

[0129] In the fifth modification example, as described above, the separation chip 100 further includes the HDF 200. Therefore, the HDF 200 can separate particles smaller than a predetermined size from the particles contained in the sample liquid, and then the separation electrode 120 can separate the dielectric particles P1 from the particles of a predetermined size or more.

[0130] Other structures and effects of the fifth modification example are the same as those of the above-described embodiment and the first to fourth modification examples.

[0131] As described above, the embodiments of the present invention have been described with reference to the drawings. However, the present invention is not limited to the above-described embodiments, and can be implemented in various forms without departing from the gist thereof. Also, by appropriately combining a plurality of components disclosed in the above-described embodiments, various inventions can be formed. For example, some components may be deleted from all the components shown in the embodiment. Further, components from different embodiments and modification examples may be appropriately combined. The drawings are schematically shown mainly for each component for easy understanding, and the thickness, length, number, interval, etc. of each illustrated component may be different from the actual ones for convenience in drawing preparation. Also, the materials, shapes, dimensions, etc. of each component shown in the above-described embodiment are examples and are not particularly limited, and various changes can be made without substantially departing from the effects of the present invention.

[0132] For example, in the above-described embodiment, an example in which the dimensions in the cross-section along the second direction Y are different between at least one tooth portion 1201 and another tooth portion 1201 has been described, but the present invention is not limited thereto. For example, at least one tooth portion 1201 and another tooth portion 1201 may have different cross-sectional shapes and / or materials along the second direction Y.

[0133] Further, for example, in the above embodiment, an example in which the electrode width W120 in the cross section along the second direction Y is different between at least one tooth portion 1201 and another tooth portion 1201 has been described, but the present invention is not limited thereto. For example, at least one tooth portion 1201 and another tooth portion 1201 may have different thicknesses (heights) in the cross section along the second direction Y.

[0134] Further, for example, in the above embodiment, an example in which the electrode portion 12 has a tooth portion 1201 and a cover portion 1031 has been described, but the present invention is not limited thereto. For example, the electrode portion 12 may not have the cover portion 1031.

[0135] Further, for example, in the second modification, an example in which the dimensions in the cross section along the second direction Y are different between at least one cover portion 1031 and another cover portion 1031 has been described, but the present invention is not limited thereto. For example, at least one cover portion 1031 and another cover portion 1031 may have different cross-sectional shapes and / or materials along the second direction Y.

[0136] Further, for example, in the second modification, an example in which the electrode width W120 in the cross section along the second direction Y is different between at least one cover portion 1031 and another cover portion 1031 has been described, but the present invention is not limited thereto. For example, at least one tooth portion 1201 and another tooth portion 1201 may have different thicknesses in the cross section along the second direction Y.

[0137] Further, for example, in the above embodiment, an example in which the electrode width W120 on the downstream side in the flow direction D is smaller than the electrode width W120 on the upstream side in the flow direction D has been described, but the present invention is not limited thereto. For example, the electrode width W120 on the downstream side in the flow direction D may be larger than the electrode width W120 on the upstream side in the flow direction D.

[0138] Also, for example, in the third modification, an example was described in which the width W1032 of the opening 1032 on the downstream side in the flow direction D is smaller than the width W1032 of the opening 1032 on the upstream side in the flow direction D. However, the present invention is not limited to this. For example, the width W1032 of the opening 1032 on the downstream side in the flow direction D may be larger than the width W1032 of the opening 1032 on the upstream side in the flow direction D.

[0139] Also, for example, in the first modification, an example was described in which the distance L120 between the electrodes on the downstream side in the flow direction D is smaller than the distance L120 between the electrodes on the upstream side in the flow direction D. However, the present invention is not limited to this. For example, the distance L120 between the electrodes on the downstream side in the flow direction D may be larger than the distance L120 between the electrodes on the upstream side in the flow direction D.

[0140] Also, for example, in the above embodiment, ∇E between the tooth portions 1201 adjacent to each other on the downstream side in the flow direction D 2 is, ∇E between the tooth portions 1201 adjacent to each other on the upstream side in the flow direction D 2 has been described as an example in which it is larger. However, the present invention is not limited to this. For example, ∇E between the tooth portions 1201 adjacent to each other on the downstream side in the flow direction D 2 is, ∇E between the tooth portions 1201 adjacent to each other on the upstream side in the flow direction D 2 may be smaller than.

Industrial Applicability

[0141] The present invention is applicable to the field of separation chips.

Explanation of Signs

[0142] 12: Electrode portion 100: Separation chip 101: Substrate 110: Flow path 1011: One side 1031: Cover portion (insulating layer) 1032: Opening 1201, 1211, 1221: Tooth part (electrode) 1205: One side 12051: First region 12052: Second region D: Flow direction ∇E: Gradient of electric field strength L120: Distance P1, P11, P12: Dielectric particles W120: Electrode width W1032: Width X: First direction Y: Second direction

Claims

1. A substrate, A plurality of electrode portions disposed on one surface of the substrate, having at least electrodes and extending in a first direction, and Comprising, The plurality of electrode portions are disposed adjacent to each other in a second direction intersecting the first direction, On one side of the plurality of electrode portions, a flow path is provided through which a liquid containing dielectric particles flows in a flow direction intersecting the first direction, At least one of the electrode portions and the other electrode portions are separation chips in which at least one of a cross-sectional shape along the second direction, dimensions in a cross-section along the second direction, and a material are different.

2. The separation chip according to claim 1, wherein at least one of the electrodes and the other electrodes are different in at least one of a cross-sectional shape along the second direction, dimensions in a cross-section along the second direction, and a material.

3. The separation chip according to claim 2, wherein the at least one electrode and the other electrode have different electrode widths in a cross-section along the second direction.

4. The other electrode is disposed on the downstream side in the flow direction compared to the at least one electrode, The separation chip according to claim 3, wherein the electrode width of the other electrode is smaller than the electrode width of the at least one electrode.

5. The electrode portion has an insulating layer disposed on one surface of the electrode, The separation chip according to claim 1, wherein at least one of the insulating layers and the other insulating layers are different in at least one of a cross-sectional shape along the second direction, dimensions in a cross-section along the second direction, and a material.

6. The insulating layer has an opening connecting the electrode and the flow path, The separation chip according to claim 5, wherein the at least one insulating layer and the other insulating layers have different widths of the opening in a cross-section along the second direction.

7. The other insulating layer is disposed on the downstream side in the flow direction compared to the at least one insulating layer, The separation chip according to claim 6, wherein the width of the opening along the second direction of the other insulating layer is smaller than the width of the opening along the second direction of the at least one insulating layer.

8. One surface of the electrode has a first region and a second region different from the first region, The insulating layer is disposed on the second region, The first region is connected to the flow path through the opening, The separation chip according to claim 6, wherein the first region is located closer to the substrate side than the second region.

9. ∇E between the adjacent electrodes on the downstream side of the flow direction 2 is the distance ∇E between the adjacent electrodes on the upstream side of the flow direction. 2 Larger than ∇E represents the gradient of the electric field strength, and is the separation chip according to any one of claims 1 to 8.

10. A substrate, a plurality of electrode portions disposed on one surface of the substrate, having at least electrodes and extending in a first direction, and comprising: the plurality of electrode portions are disposed adjacent to each other in a second direction intersecting the first direction, on one side of the plurality of electrode portions, a flow path is provided through which a liquid containing dielectric particles flows in a flow direction intersecting the first direction, a separation chip in which the distance between at least one pair of electrodes is different from the distance between other pairs of electrodes.

11. The separation chip according to claim 10, wherein the distance between the other pair of electrodes on the downstream side in the flow direction is smaller than the distance between the at least one pair of electrodes on the upstream side in the flow direction.

12. the electrode portion has an insulating layer disposed on one surface of the electrode, the insulating layer has an opening connecting the electrode and the flow path, one surface of the electrode has a first region and a second region different from the first region, the insulating layer is disposed on the second region, the first region is connected to the flow path through the opening, the separation chip according to claim 10, wherein the first region is located closer to the substrate side than the second region.

13. ∇E between the electrodes adjacent to each other on the downstream side in the flow direction 2 is larger than ∇E between the electrodes adjacent to each other on the upstream side in the flow direction 2 and is larger than that ∇E represents the gradient of the electric field strength, and is the separation chip according to any one of claims 10 to 12.

14. A substrate, a plurality of electrode portions disposed on one surface of the substrate, having at least electrodes and extending in a first direction, and comprising: the plurality of electrode portions are disposed adjacent to each other in a second direction intersecting the first direction, on one side of the plurality of electrode portions, a flow path is provided through which a liquid containing dielectric particles flows in a flow direction intersecting the first direction, ∇E between at least one of said electrodes 2 is different from ∇E between the other said electrodes 2 in that a separation chip, wherein ∇E represents the gradient of the electric field strength.

Images