JP2022168681A - Detection substrate, detection unit, and detection device - Google Patents

Abstract

To perform detection with high accuracy regardless of an amount of specimens.SOLUTION: A detection substrate 10 comprises: a dielectric substrate 11; a waveguide 13 that covers part of a surface 11a of the dielectric substrate 11 and radiates microwaves; a diamond crystal 14 that is located on a surface 11a side of the dielectric substrate 11 where the waveguide 13 is located and has an NV center 15 formed on a surface 14b in contact with the waveguide 13 and on the opposite side of a surface 14a; and a thin film 16 that covers the surface 14b of the diamond crystal 14 on which the NV center 15 is formed and has primary antibodies 17 immobilized on a surface 16a. The detection substrate detects magnetic beads that are coupled to specimens coupled to the primary antibodies 17 and have secondary antibodies immobilized thereto on the surface 14a of the diamond crystal 14 on which the NV center 15 is formed.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to detection substrates, detection units, and detection devices.

In Patent Document 1, an aqueous solution containing a specimen and a secondary antibody is dropped onto a substrate on which the primary antibody is immobilized, and the specimen sandwiched between the primary antibody and the secondary antibody is treated with a dye or dye bound to the secondary antibody. Techniques for detection by fluorescent substances have been disclosed.

JP 2015-230221 A

With the technique described in Patent Document 1, when the amount of the sample is insufficient, it is difficult to confirm the change in the dye, and there is a risk that the dye will not be detected correctly. Thus, there is room for improvement in detection accuracy.

A detection substrate according to one aspect includes a dielectric substrate, a waveguide that covers a part of the surface of the dielectric substrate and irradiates microwaves, and a surface side of the dielectric substrate where the waveguide is located. a diamond crystal having NV centers formed on the surface opposite to the surface in contact with the waveguide; and covering the surface of the diamond crystal having the NV centers formed thereon, a primary antibody being immobilized on the surface. magnetic beads on which a secondary antibody is immobilized that binds to the analyte bound to the primary antibody is detected on the surface of the diamond crystal where the NV center is formed.

A detection unit according to one aspect is a detection unit having the above-described detection substrate, a second dielectric substrate, and magnetic beads to which the secondary antibody is immobilized, wherein the second dielectric substrate is The magnetic beads have recesses in which the detection substrate is fitted, the upper surface of the second dielectric substrate is connected so as to be flat with the upper surface of the detection substrate, and the secondary antibody is immobilized on the magnetic beads. , is placed on the upper surface of the second dielectric substrate, and is moved by dropping the sample liquid.

A detection device according to one aspect is a detection device including the detection unit described above and an optical pickup, wherein the optical pickup includes a light source for irradiating light onto the detection substrate included in the detection unit, and the detection substrate. and a detector that detects the fluorescence of

A detection substrate according to one aspect includes a dielectric substrate and a thin film that covers a portion of the surface of the dielectric substrate and has a primary antibody immobilized on the surface, and the surface of the dielectric substrate on which the thin film is located Then, the magnetic beads on which the secondary antibody is immobilized, which binds to the specimen bound to the primary antibody, are detected by facing the diamond crystal forming the NV center.

A detection unit according to one aspect is a detection unit including the detection substrate described above and magnetic beads to which the secondary antibody is immobilized, wherein the magnetic beads to which the secondary antibody is immobilized are the dielectric It is located at one end of the surface on which the thin film of the body substrate is located and is displaced by the drop of sample liquid.

A detection device according to one aspect is a detection device comprising the detection unit described above, the diamond crystal, a waveguide, and an optical pickup, wherein the diamond crystal forms an NV center on one surface, The waveguide is positioned on the surface of the diamond crystal opposite to the surface on which the NV center is formed, and the optical pickup is a light source for irradiating the detection substrate included in the detection unit with light. and a detector for detecting the fluorescence of the detection substrate.

According to the detection substrate, the detection unit, and the detection device according to one aspect of the present disclosure, detection can be performed with high accuracy regardless of the amount of specimen.

FIG. 1 is a cross-sectional view of a detection substrate according to the first embodiment. FIG. 2 is a schematic diagram illustrating an example of the arrangement of thin films on the detection substrate according to the first embodiment. FIG. 3 is a cross-sectional view of the detection unit according to the first embodiment. FIG. 4 is a diagram illustrating a detection process using the detection device according to the first embodiment. FIG. 5 is a diagram for explaining the detection process using the detection device according to the first embodiment. FIG. 6 is a diagram illustrating a detection process using the detection device according to the first embodiment. FIG. 7 is a cross-sectional view of the detection device according to the second embodiment. FIG. 8 is a cross-sectional view of a detection device according to a modification of the second embodiment.

A detection substrate, a detection unit, and a detection device according to the first embodiment will be described below. The detection substrate, detection unit and detection device are for detecting analytes.

[First embodiment]
(Detection board)
FIG. 1 is a cross-sectional view of a detection substrate 10 according to the first embodiment. As shown in FIG. 1, the detection substrate 10 is a substrate on which a primary antibody 17 against an antigen Y contained in a sample liquid X, which is a sample, is arranged. The detection substrate 10 constitutes a test line. The detection substrate 10 includes a dielectric substrate 11 , an antenna conductor 12 , a waveguide 13 , a diamond crystal 14 and a thin film 16 .

An antenna conductor 12 and a waveguide 13 are formed on the surface 11a of the dielectric substrate 11 . The dielectric substrate 11 is made of, for example, SiO ₂ , a glass material, a ceramic material, or a resin material such as glass epoxy. Dielectric substrate 11 is formed in a plate shape.

Antenna conductor 12 transmits microwaves to irradiate NV center 15 of diamond crystal 14 . Antenna conductor 12 is interposed between surface 11 a of dielectric substrate 11 and surface 14 b of diamond crystal 14 . The antenna conductor 12 has, for example, a ring shape when viewed in the normal direction of the surface 11a of the dielectric substrate 11 (hereinafter referred to as “plan view”).

The waveguide 13 is a high frequency line conductor. The waveguide 13 covers part of the surface 11a of the dielectric substrate 11 and irradiates the NV center 15 of the diamond crystal 14 with microwaves. Waveguide 13 is interposed between surface 11 a of dielectric substrate 11 and surface 14 b of diamond crystal 14 . The waveguide 13 transmits microwaves transmitted by the antenna conductor 12 . The waveguide 13 is made of, for example, SiO ₂ , a glass material, a ceramic material, or a resin material such as glass epoxy.

Diamond crystal 14 is a so-called diamond sensor. The diamond crystal 14 is located on the side of the surface 11a of the dielectric substrate 11 where the waveguide 13 is located. The diamond crystal 14 has an NV center 15 formed on the surface 14a opposite to the surface 14b in contact with the waveguide 13 . A primary antibody 17 is immobilized on the surface 14a.

The diamond crystal 14 has a side length d11 of 200 μm, for example. The diamond crystal 14 has a thickness d12 of, for example, 100 μm.

A single NV center 15 may be arranged on the surface 14a side of the diamond crystal 14, or a plurality thereof may be arranged. In this embodiment, FIG. 1 and the like illustrate a state in which a plurality of NV centers 15 are arranged.

The NV center 15 is a complex defect in the diamond crystal 14 in which carbon is substituted with nitrogen where it should exist and vacancies are present at adjacent positions. The NV center 15 lacks part of the degenerate shared electron pairs. The NV center 15 has electrons with two levels of orbital angular momentum of m=0 and m=±1 at zero magnetic field. Electrons with m=±1 have a magnetic moment and are therefore affected by an external magnetic field. The intensity of the external magnetic field can be detected by detecting the electron spin resonance caused by these using light waves and microwaves.

Electrons in the NV center 15 are excited by light with a wavelength of 532 nm and emit fluorescence with a wavelength of 638 nm in the process of relaxation. This fluorescence process is unlikely at the electron spin resonance frequency. Therefore, by using this property, the electron state of m=±1 can be observed. At the NV center 15 of the diamond crystal 14, the electron spin resonance frequency at zero magnetic field is known to be approximately 2.87 GHz. Fluorescence with a wavelength of 638 nm is quenched when microwaves at the frequency of this resonance point (resonance frequency) are irradiated. Further, the resonance frequency of the microwave changes due to the change in the state of the electrons of m=±1 according to the magnitude of the external magnetic field and the like. Then, the magnetic field can be detected by capturing this change as the frequency change of fluorescence intensity.

Thin film 16 covers surface 14a of diamond crystal 14 where NV center 15 is formed. The thin film 16 is adjacent to the surface 14a of the diamond crystal 14 on at least a portion of its periphery. The membrane 16 can have various shapes, such as rectangular, circular and polygonal. The thin film 16 is formed of a hydrophilic polymer such as Au, polyvinylpyrrolidone, polyvinyl alcohol, polyethylene glycol, vinyl acetate and vinylamine copolymer, cellulose and its derivatives, polysaccharides, collagen, polyamino acid, and the like.

FIG. 2 is a schematic diagram illustrating an example of arrangement of the thin film 16 on the detection substrate 10 according to the first embodiment. FIG. 2 is a plan view of the detection substrate 10. FIG. As shown in FIG. 2, one or more thin films 16 are disposed on the surface 14 a of the diamond crystal 14 . The thin films 16 may be periodically arranged on the surface 14a. In this embodiment, the thin film 16 is arranged in a grid pattern on the surface 14a. Along each side of the detection substrate 10, the surface 14a of the diamond crystal 14 and the thin film 16 are alternately exposed. In this embodiment, 10×10 thin films 16 are arranged on the surface 14a. The thin film 16 has a side length d21 of 1 μm, for example. The interval between adjacent thin films 16 in the direction of each side of the detection substrate 10 is, for example, 1 μm.

Primary antibody 17 is the primary antibody for antigen Y. One to 1000 primary antibodies 17 are arranged on one thin film 16 . The primary antibody 17 may cover the entire surface of the thin film 16 . The primary antibody 17 is arranged separately from the magnetic beads 23 and the secondary antibody 22, which will be described later.

The detection substrate 10 formed in this way has a surface 14a on which the NV center 15 of the diamond crystal 14 is formed, and the specimen bound with the primary antibody 17 (antigen Y in the specimen liquid X shown in FIG. 3) The bound magnetic beads 23 on which the secondary antibody 22 is immobilized are detected.

(detection unit)
FIG. 3 is a cross-sectional view of the detection unit 20 according to the first embodiment. The detection unit 20 functions as a preparation for the detection device 40, which will be described later. The detection unit 20 has a detection substrate 10, a second dielectric substrate 21, and magnetic beads 23 to which a secondary antibody 22 is immobilized. The second dielectric substrate 21 has a recess 24 in which the detection substrate 10 is fitted. The surface 21a, which is the upper surface of the second dielectric substrate 21, is connected to the upper surface of the detection substrate 10 so as to be flat.

The second dielectric substrate 21 is a support substrate that supports the detection substrate 10 . The second dielectric substrate 21 includes a waveguide for transmitting microwave signals to the detection substrate 10 and an antenna conductor connected to the waveguide. The second dielectric substrate 21 is formed in a plate shape. The detection substrate 10 is arranged in the central portion of the surface 21 a of the second dielectric substrate 21 . The second dielectric substrate 21 is made of, for example, SiO ₂ , a glass material, a ceramic material, or a resin material such as glass epoxy. The second dielectric substrate 21 is formed in a plate shape. The second dielectric substrate 21 may be formed integrally with the dielectric substrate 11 .

A secondary antibody 22 is positioned on one end side of the surface 21 a of the second dielectric substrate 21 . Secondary antibody 22 is a secondary antibody for antigen Y. Secondary antibody 22 is immobilized on magnetic beads 23 arranged on surface 21 a of second dielectric substrate 21 .

A magnetic bead 23 is arranged at one end of the surface 21 a of the second dielectric substrate 21 . Magnetic beads 23 are immobilized with secondary antibodies 22 that move toward the other end when sample liquid X is dropped. One or more secondary antibodies 22 are immobilized on the surface of one magnetic bead 23 . The magnetic beads 23 have a particle size of, for example, 30 nm or more and 60 nm or less. The magnetic beads 23 are iron oxides such as Fe ₂ O ₃ and Fe ₃ O ₄ whose surfaces are coated with a hydrophilic polymer.

The recess 24 is formed in the surface 21a of the second dielectric substrate 21 in a concave shape. The detection substrate 10 is fitted into the recess 24 . The concave portion 24 is arranged in the intermediate portion of the surface 21 a of the second dielectric substrate 21 . The concave portion 24 is separated from the position where the secondary antibody 22 and the magnetic beads 23 are arranged.

Absorbent pad 25 is disposed on the other end of surface 21 a of second dielectric substrate 21 . The absorbent pad 25 absorbs the sample liquid X and the secondary antibody 22 immobilized on the magnetic beads 23 that flowed on the surface 21 a of the second dielectric substrate 21 . The absorbent pad 25 absorbs the specimen liquid X and the secondary antibody 22 immobilized on the magnetic beads 23 that have not bound to the primary antibody 17 on the detection substrate 10 . Absorbent pad 25 is spaced apart from recess 24 .

On the surface 21a of the second dielectric substrate 21, the secondary antibody 22 immobilized on the magnetic beads 23 and the absorbent pad 25 are arranged with the concave portion 24 interposed therebetween. The magnetic beads 23 to which the secondary antibody 22 is immobilized are arranged on the surface 21a of the second dielectric substrate 21, and are moved by dropping the specimen liquid X. As shown in FIG.

(detection device)
The detection device 40 detects the antigen Y contained in the sample liquid X. FIG. As shown in FIG. 3, the detection device 40 has a detection unit 20 and an optical pickup 30 .

The optical pickup 30 is arranged to face the detection substrate 10 . The optical pickup 30 inputs and outputs light to the NV center 15 of the diamond crystal 14 . The optical pickup 30 detects magnetism of the detection substrate 10 . In this embodiment, the optical pickup 30 performs detection while scanning the detection substrate 10 . The optical pickup 30 has a light emitting element 31 as a light source and a light receiving element 32 as a detector. The optical pickup 30 is controlled by a control circuit (not shown). The control circuit controls light emission in the light emitting element 31 . The control circuit controls light reception by the light receiving element 32 . The control circuit processes the red fluorescence signal received by the light receiving element 32 . The control circuit outputs the strength of the magnetic field as a result.

The light emitting element 31 emits light to the detection substrate 10 included in the detection unit 20 . The light emitting element 31 is a laser diode. The light emitting element 31 emits laser light with a wavelength of 527 nm, for example, under the control of the control circuit. The light emitting element 31 emits green excitation light. The light emitting element 31 emits excitation light that irradiates the diamond crystal 14 .

The light receiving element 32 detects fluorescence of the detection substrate 10 . The light receiving element 32 is a photodiode. The light receiving element 32 receives fluorescence from the NV center 15 of the diamond crystal 14 under the control of the control circuit. The light receiving element 32 receives fluorescence. The light receiving element 32 receives fluorescence emitted by the excitation light from the diamond crystal 14 .

(Detection method)
A method of detecting an antigen Y such as a virus using the detection unit 20 will be described with reference to FIGS. 4 to 6. FIG. FIG. 4 is a diagram illustrating a detection process using the detection device 40 according to the first embodiment. FIG. 5 is a diagram for explaining the detection process using the detection device 40 according to the first embodiment. FIG. 6 is a diagram illustrating a detection process using the detection device 40 according to the first embodiment. First, as shown in FIG. 4, a specimen liquid X containing an antigen Y such as a virus is dropped onto the magnetic beads 23 and the secondary antibody 22 on the second dielectric substrate 21 .

As shown in FIG. 5 , in sample liquid X, part of antigen Y binds to secondary antibody 22 . The dropped sample liquid X diffuses on the second dielectric substrate 21 while a part of the antigen Y is bound to the secondary antibody 22 . As a result, the magnetic beads 23 adhere to the plurality of thin films 16 of the detection substrate 10 . The specimen liquid X flows through the detection substrate 10 toward the absorption pad 25 side.

As shown in FIG. 6, the antigen Y bound to the secondary antibody 22 binds to the primary antibody 17 in a sandwich manner to form a binding site Q. As shown in FIG. In the binding portion Q, the antigen Y is sandwiched between the primary antibody 17 and secondary antibody 22 . The binding portion Q is arranged in the order of the primary antibody 17 , the antigen Y, the secondary antibody 22 and the magnetic beads 23 in order of proximity to the second dielectric substrate 21 . The magnetic bead 23 is located at the farthest position from the second dielectric substrate 21 in the coupling portion Q. As shown in FIG. At the binding portion Q, the number of magnetic beads 23 corresponding to the concentration of the antigen Y in the sample liquid X is bound.

The magnetic beads 23 that have not bound to the antigen Y do not remain on the thin film 16 of the second dielectric substrate 21, but move toward the absorption pad 25 located at the end opposite to the position where the sample liquid X was dropped. Moving.

An optical pickup 30, which is a detection probe, is brought close to or in contact with the position where the primary antibody 17 was immobilized. Prior to that, a magnetic field is applied to the magnetic beads 23 . The magnetic beads 23 are magnetized. The magnetic field of magnetic beads 23 acts on NV center 15 . More specifically, the magnetic field of the magnetic bead 23 acts on the NV center 15 located adjacent to the thin film 16 where the surface 14a of the diamond crystal 14 is exposed. The optical pickup 30 receives the electron spin resonance signal of the NV center 15 of the portion where the surface 14a of the diamond crystal 14 is exposed as fluorescence. Thereby, the optical pickup 30 detects the magnetic charge of the magnetic beads 23 of the coupling portion Q, which is the object to be measured. The optical pickup 30 detects the concentration according to the number of magnetic beads 23 . The controller calculates the strength of the magnetic field from the signal that is the detection result of the optical pickup 30 and outputs the result.

(effect)
As described above, in this embodiment, the primary antibody 17 is placed on the thin film 16 placed on the surface 14 a of the diamond crystal 14 . In this embodiment, on the surface 14a of the diamond crystal 14, the magnetic beads 23 on which the secondary antibody 22 is immobilized, which binds to the specimen to which the primary antibody 17 is bound, are detected. According to this embodiment, a weak magnetic field can be detected by using the NV center 15 . As described above, the present embodiment can detect a sample with high accuracy even if the amount of the sample is small.

In this embodiment, a diamond crystal 14 is integrated with the sensing substrate 10 . This embodiment can simplify the configuration of the detection device 40 .

In this embodiment, the detection substrate 10 fits into the recess 24 of the second dielectric substrate 21 . In this embodiment, magnetic beads 23 and secondary antibodies 22 are immobilized on the second dielectric substrate 21 . According to this embodiment, the area using the diamond crystal 14 can be reduced.

In this embodiment, the optical pickup 30 irradiates the detection substrate 10 with light and detects the fluorescence of the detection substrate 10 . This embodiment can detect with high accuracy even if the amount of specimen is small.

In this embodiment, a plurality of thin films 16 are arranged on the surface 14 a of the diamond crystal 14 . In this embodiment, the thin film 16 is, for example, periodically arranged on the surface 14a of the diamond crystal 14 . According to this embodiment, even when the amount of specimen is small, the possibility that the antigen Y binds to the primary antibody 17 and the secondary antibody 22 in a sandwich manner on any of the thin films 16 can be increased. As a result, even if the amount of specimen is small, this embodiment can detect the specimen with high accuracy. In addition, in this embodiment, by averaging the detection results of the amount of antigen Y adhering to the binding site Q in a plurality of thin films 16, stable quantification with good reproducibility can be achieved. This embodiment can easily and accurately quantify the number of antigens Y contained in the sample liquid X adhering to the binding portion Q. FIG.

In this embodiment, the thin film 16 is arranged on the surface 14a of the diamond crystal 14 in a grid pattern. In this embodiment, adjacent to the thin film 16, the surface 14a of the diamond crystal 14 is exposed. In other words, in this embodiment, adjacent to the joint Q, the surface 14a of the diamond crystal 14 is exposed. This embodiment can reduce the distance between the coupling portion Q and the NV center 15 . In this embodiment, the magnetic field of the magnetic beads 23 included in the coupling portion Q can efficiently act on the NV center 15 . In this embodiment, light can be input and output from the exposed surface 14 a of the diamond crystal 14 to the NV center 15 . In this embodiment, since the coupling portion Q is adjacent to the NV center 15, even a weak magnetic field such as the magnetic field generated by one magnetic bead 23 can be detected. According to this embodiment, detection can be performed with high accuracy.

[Second embodiment]
FIG. 7 is a cross-sectional view of the detection device 40 according to the second embodiment. FIG. 7 illustrates the middle portion of the dielectric substrate 11 . This embodiment differs from the first embodiment in that it does not have the second dielectric substrate 21 and in the arrangement of the diamond crystals 14 .

(Detection board)
The detection substrate 10 has a dielectric substrate 11 and a thin film 16 . Detection substrate 10 does not include diamond crystals 14 .

The dielectric substrate 11 includes a lower dielectric substrate 11A and an upper dielectric substrate 11B. In this embodiment, the dielectric substrate 11 functions as the dielectric substrate 11 and the second dielectric substrate 21 of the first embodiment. More specifically, the thin film 16 is placed in the middle of the dielectric substrate 11, the magnetic beads 23 to which the secondary antibody 22 is immobilized are placed at one end, and the absorbent pad 25 is placed at the other end.

The lower dielectric substrate 11A is configured similarly to the dielectric substrate 11 of the first embodiment.

The upper dielectric substrate 11B faces the lower dielectric substrate 11A with the antenna conductor 12 interposed therebetween. The upper dielectric substrate 11B is arranged instead of the diamond crystal 14 of the first embodiment. The upper dielectric substrate 11B is made of, for example, SiO ₂ , a glass material, a ceramic material, or a resin material such as glass epoxy. Upper dielectric substrate 11B is formed in a plate shape.

Antenna conductor 12 is positioned between lower dielectric substrate 11A and upper dielectric substrate 11B.

Waveguide 13 is positioned between lower dielectric substrate 11A and upper dielectric substrate 11B.

The thin film 16 covers part of the intermediate portion of the surface 11Ba of the upper dielectric substrate 11B. A primary antibody 17 is immobilized on the surface 11Ba of the thin film 16 . One or more thin films 16 are arranged on the surface 11Ba of the upper dielectric substrate 11B. The thin films 16 are periodically arranged on the surface 11Ba of the upper dielectric substrate 11B.

(detection unit)
The detection unit 20 has a detection substrate 10 and magnetic beads 23 to which secondary antibodies 22 are immobilized.

A secondary antibody 22 is positioned on one end side of the surface 11Ba of the upper dielectric substrate 11B. Secondary antibody 22 is immobilized on magnetic beads 23 arranged on surface 11Ba of upper dielectric substrate 11B.

A magnetic bead 23 is arranged at one end of the surface 11Ba of the upper dielectric substrate 11B.

Absorbing pad 25 is disposed at the other end of surface 11Ba of upper dielectric substrate 11B. The absorbent pad 25 absorbs the sample liquid X and the secondary antibody 22 immobilized on the magnetic beads 23 that have flowed on the surface 11Ba of the upper dielectric substrate 11B.

(detection device)
The detection device 40 has a detection unit 20 , a diamond crystal 14 and an optical pickup 30 .

Diamond crystal 14 faces thin film 16 . Diamond crystals 14 are brought into close proximity or close contact with thin film 16 . In this embodiment, a joint Q is formed between the diamond crystal 14 and the thin film 16 . The NV center 15 is arranged on the side of the surface 14 b of the diamond crystal 14 facing the thin film 16 .

The optical pickup 30 inputs light from just above the NV center 15 of the diamond crystal 14 . The optical pickup 30 includes a light emitting element 31 which is a light source for irradiating the detection substrate 10 provided in the detection unit 20 with light, and a light receiving element 33 which is a detector for detecting fluorescence of the detection substrate 10 .

(Detection method)
A specimen liquid X containing an antigen Y such as a virus is dropped onto the magnetic beads 23 and the secondary antibody 22 on the surface 11Ba of the upper dielectric substrate 11B of the detection substrate 10 provided in the detection unit 20 configured as described above. Then, on the surface 11Ba of the upper dielectric substrate 11B where the thin film 16 is located, the magnetic beads 23 on which the secondary antibody 22 is immobilized, which binds to the analyte bound to the primary antibody 17, form the NV center 15. The diamond crystal 14 is made to face and detected.

(effect)
As described above, in this embodiment, the diamond crystal 14 is close to or adheres to the thin film 16 . Thus, in this embodiment, the magnetic beads 23 of the coupling portion Q are positioned closer to the NV center 15 than in the first embodiment. This embodiment makes it easier to detect even weak magnetic fields. According to this embodiment, more accurate detection can be performed.

In this embodiment, the sample liquid X is dropped onto the surface 11Ba of the upper dielectric substrate 11B of the detection substrate 10. FIG. In this embodiment, the specimen liquid X does not adhere to the diamond crystal 14 . According to this embodiment, the diamond crystal 14 can be reused in magnetic field detection.

[Modification]
FIG. 8 is a cross-sectional view of a modification of the detection device 40 according to a modification of the second embodiment. The basic configuration of the detection device 40 is similar to that of the second embodiment. This embodiment differs from the second embodiment in the structure of the dielectric substrate 11 and in that the antenna conductor 12 is arranged on the diamond crystal 14 .

Dielectric substrate 11 is in the shape of a single plate.

The antenna conductor 12 is located on the surface 14a of the diamond crystal 14 opposite to the surface 14b on which the NV center 15 is formed. In this embodiment, the antenna conductor 12 is formed in a ring shape.

The waveguide 13 is located on the surface 14a of the diamond crystal 14 opposite to the surface 14b on which the NV center 15 is formed.

As described above, in the modified example, the NV center 15 of the diamond crystal 14 can be irradiated with microwaves from the waveguide 13 positioned near the NV center 15 in the same manner as in the first embodiment. According to the modification, the detection board 10 and the detection unit 20 can be simplified.

The disclosed embodiments of the present application can be modified without departing from the spirit and scope of the invention. Furthermore, the embodiments disclosed in the present application and their modifications can be combined as appropriate.

Specific embodiments have been described for the purpose of fully and clearly disclosing the claimed technology. However, the appended claims should not be limited to the above embodiments, but all variations and alternatives that can be created by those skilled in the art within the scope of the basics shown in this specification. should be configured to embody a

Reference Signs List 10 detection substrate 11 dielectric substrate 11a surface 12 antenna conductor 13 waveguide 14 diamond crystal 14a surface 14b surface 15 NV center 16 thin film 17 primary antibody 20 detection unit 21 second dielectric substrate 21a surface 22 secondary antibody 23 magnetic bead 24 Recess 25 Absorption Pad 30 Optical Pickup 31 Light Emitting Element 32 Light Receiving Element 40 Detecting Device X Specimen Liquid Y Antigen

Claims (9)

a dielectric substrate;
a waveguide that covers a portion of the surface of the dielectric substrate and irradiates microwaves;
a diamond crystal located on the surface side of the dielectric substrate where the waveguide is located and having an NV center formed on the surface opposite to the surface in contact with the waveguide;
a thin film covering the surface of the diamond crystal on which the NV center is formed and having a primary antibody immobilized on the surface;
A detection substrate for detecting magnetic beads on which a secondary antibody is immobilized, which binds to the analyte to which the primary antibody is bound, on the surface of the diamond crystal where the NV center is formed. 2. The detection substrate according to claim 1, wherein a plurality of said thin films are arranged on said surface where said NV centers of said diamond crystal are formed. A detection unit comprising the detection substrate according to claim 1 or 2, a second dielectric substrate, and magnetic beads on which the secondary antibody is immobilized,
the second dielectric substrate has a recess positioned to fit the detection substrate;
the upper surface of the second dielectric substrate is connected to the upper surface of the detection substrate so as to be flat;
A detection unit in which the magnetic beads to which the secondary antibody is immobilized are arranged on the upper surface of the second dielectric substrate and are moved by dropping the specimen liquid. A detection device comprising the detection unit according to claim 3 and an optical pickup,
The optical pickup is
a light source that irradiates the detection substrate included in the detection unit with light;
and a detector that detects the fluorescence of the detection substrate. a dielectric substrate;
a thin film covering a portion of the surface of the dielectric substrate and having a primary antibody immobilized on the surface;
On the surface where the thin film of the dielectric substrate is located, the magnetic beads on which the secondary antibody is immobilized, which binds to the analyte bound to the primary antibody, are detected by facing the diamond crystal forming the NV center. detection board. The detection substrate according to claim 5, wherein a plurality of said thin films are arranged on said surface of said dielectric substrate. A detection unit comprising the detection substrate according to claim 5 or 6 and magnetic beads on which the secondary antibody is immobilized,
The magnetic bead on which the secondary antibody is immobilized is located at one end of the surface of the dielectric substrate where the thin film is located, and is moved by dropping the sample liquid. A detection device comprising the detection unit according to claim 7, the diamond crystal, and an optical pickup,
the dielectric substrate of the detection substrate included in the detection unit has a lower dielectric substrate and an upper dielectric substrate;
the detection substrate included in the detection unit has a waveguide positioned between the lower dielectric substrate and the upper dielectric substrate;
The diamond crystal forms an NV center on one side,
The detection device, wherein the optical pickup includes a light source that irradiates the detection substrate with light, and a detector that detects fluorescence of the detection substrate. A detection device comprising the detection unit according to claim 7, the diamond crystal, a waveguide, and an optical pickup,
The diamond crystal forms an NV center on one side,
The waveguide is located on the surface of the diamond crystal opposite to the surface on which the NV center is formed,
A detection device, wherein the optical pickup includes a light source that irradiates light onto the detection substrate included in the detection unit, and a detector that detects fluorescence of the detection substrate.

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