JP6357619B2 - Sensing sensor and sensing device - Google Patents

Description

  The present invention relates to a sensing sensor for sensing a sensing object contained in a sample liquid based on an oscillation frequency of a piezoelectric vibrator such as a crystal vibrator and a sensing device including the sensing sensor.

  In the clinical field, for example, a simple test method called POCT (Point of core TEST) typified by self-monitoring of blood glucose level and influenza virus test is widespread, and in such test, QCM (Quartz Crystal Microbalance) It has been studied to use a sensor that uses a sensor. Briefly describing the QCM, a sample liquid containing a sensing object is supplied to the surface of a crystal resonator provided in the sensing device. Then, the sensing object in the sample liquid is adsorbed on the surface of the crystal unit, and the oscillation frequency of the crystal unit changes according to the amount of adsorption of the sensing object due to the mass load effect. Based on the change in the oscillation frequency, detection or quantification of the sensing object in the sample liquid is performed.

  In Patent Document 1, a sample liquid is supplied to a crystal resonator having an adsorption film that adsorbs a sensing object on one side thereof, and the sensing object is determined based on the amount of change in the oscillation frequency of the crystal oscillator. A batch-type sensing sensor for sensing is disclosed. FIG. 12 shows an example of the sensing sensor. A crystal resonator 91 is provided so as to close a through-hole 90 formed in the wiring substrate 9, and a sheet 98 having a recess 92 formed in the lower portion is used as a crystal resonator. The flow path 92 for the sample solution is formed by disposing the cover 93 on one end side of the wiring board 9 from the outside, pressing the sheet 98 against the wiring board 9 by the pressure of the cover 93. . Since the concave portion of the sheet 98 and the flow path of the sample liquid are the same, the same symbol 92 is given. Then, the sample liquid supplied from the supply port 931 formed in the cover 93 flows into the flow path 92 from the inlet side capillary member 94, and flows into the drainage region 96 through the outlet side capillary member 95 by capillary action. It is configured to flow out. Reference numeral 97 denotes a film provided on the other surface side of the wiring board 9 so as to close the through hole 90.

  The batch type sensor having such a structure is effective in preventing the occurrence of a gap between components due to the dimensional variation of each component by interposing the sheet 98. However, at the same time, since the cover 93 presses the sheet 98, the ceiling portion of the flow path 92 is pressurized, so that the height of the flow path 92 may be reduced unevenly.

  In the batch type sensor, there is a demand for narrowing the height of the flow path 92 in order to improve the contact rate between the sensing object and the surface of the crystal unit 91. However, if the height of the channel 92 is lowered by increasing the pressure from the cover 93 to be fitted, there is a concern that the channel 92 may be completely crushed or the crystal unit 91 may be lost. is there. Further, although a method of reducing the pressure from the cover 93 that is fitted after the concave portion 92 of the sheet 98 is formed to be narrow is conceivable, the sample liquid may leak out of the sensor.

  In Patent Document 2, a piezoelectric vibrator is disposed on a lower case in which an opening and a groove surrounding the opening are formed, a sample liquid inlet and a protrusion corresponding to the groove are formed in the upper case, A method for configuring a piezoelectric sensor by fitting a groove and a protrusion of an upper case is disclosed. However, this document does not mention the height of the flow path of the sample liquid on the piezoelectric vibrator, and the problem to be solved is different from the present invention.

JP 2012-145 566 A JP-A-9-145583

  The present invention has been made under such circumstances, and an object of the present invention is to provide a sensing sensor and a sensing device with improved measurement sensitivity for a sensing object.

The sensing sensor of the present invention is
A wiring board having a connection terminal connected to a measuring instrument for measuring the oscillation frequency and having a recess formed on one side;
The piezoelectric piece is provided with an excitation electrode, and is fixed to the wiring board so as to close the recess and to have a vibration region facing the recess, and the excitation electrode is electrically connected to the connection terminal. A piezoelectric vibrator formed with an adsorption film that adsorbs a sensing object in the sample liquid,
A flow path forming member provided so as to cover a region on one surface side of the wiring board including the piezoelectric vibrator, and having a sample liquid inlet;
When the one surface side of the wiring board is the upper surface side, a pressing member that fixes the flow path forming member in a pressed state against the wiring board by engaging with a member positioned below the flow path forming member. When,
The sample liquid formed between the wiring board and the flow path forming member by pressing by the pressing member and distributed to the injection port flows from one end side to the other end side on one surface side of the piezoelectric vibrator. A flow path to be
A buffer member that is provided between the flow path forming member and the pressing member or on the other surface side of the wiring board and absorbs an excessive amount of pressure from the pressing member ;
The flow path forming member is pressed and fixed by the pressing member even when the buffer member is not present .

The sensing device of the present invention also has
The sensing device includes the sensing sensor and the measuring device.

  According to the sensing sensor of the present invention, the sample liquid moves from the inlet to the drainage flow path via the flow path on one surface side of the piezoelectric vibrator, and at this time, the sensing object contained in the sample liquid is the piezoelectric vibrator. It is adsorbed by the adsorbing film provided on the surface. The flow path on the one surface side of the piezoelectric vibrator is configured by pressing the flow path forming member on which the flow path is formed against the wiring substrate on which the piezoelectric vibrator is fixed by a pressing member. Here, by arranging a buffer member having a hardness lower than that of the flow path forming member on the other surface side of the wiring board in contact with the flow path forming member, an excessive pressure component of the pressure from the pressing member is affected. Since it is absorbed by the buffer member, it is possible to prevent the flow path from being crushed by excessive pressure. Therefore, since the height of the flow path can be set narrow, the contact rate between the sensing object and the adsorption film provided on the piezoelectric vibrator can be improved, and as a result, sensing is performed. The sensitivity of the entire sensor can be increased.

1 is a perspective view of a sensing device according to the present invention. It is a disassembled perspective view of the sensing sensor which comprises a sensing apparatus. It is the disassembled perspective view which showed the upper surface side of each part of a detection sensor. It is the disassembled perspective view which showed the lower surface side of a part of detection sensor. It is a decomposition | disassembly longitudinal cross-sectional view of a detection sensor. It is a longitudinal cross-sectional view of a detection sensor. It is a block diagram which shows the structure of a sensing apparatus. It is a longitudinal cross-sectional view which shows a mode that a liquid distribute | circulates in a detection sensor. It is a longitudinal cross-sectional view which shows the other example of a sensing sensor. It is a longitudinal cross-sectional view which shows the other example of a sensing sensor. It is a graph which shows the measurement result by the sensing sensor of this invention. It is a vertical side view which shows the prior art example of a sensing sensor.

  Hereinafter, the sensing device 1 of the present invention will be described. The sensing device 1 is configured to detect the presence or absence of an influenza virus in a sample solution obtained from, for example, a human nasal wipe. As shown in the external configuration diagram of FIG. 1, the sensing device 1 includes an oscillation circuit unit 12 and an arithmetic device 13 connected to the oscillation circuit unit 12 via, for example, a coaxial cable 14, and these oscillation circuit units. 12 and the arithmetic unit 13 constitute a measuring instrument 11. A display unit 16 is provided on the front surface of the casing 15 of the arithmetic device 13, and the display unit 16 serves to display a measurement result such as a frequency or a change in frequency. The sensing sensor 2 is detachably connected to the oscillation circuit unit 12.

  Next, the detection sensor 2 will be described in detail with reference to FIGS. 2 is a perspective view showing a state in which a lid (upper cover body 21) that is a pressing member in the sensing sensor 2 is removed, and FIG. 3 is an exploded perspective view showing the front side (upper side) of each member of the sensing sensor 2. 4 is a perspective view showing the back side (lower surface side) of some members of the sensing sensor 2. FIG. 5 is an exploded longitudinal sectional view of the sensing sensor 2 cut along the length direction (X-axis direction in the drawing). FIG. 6 is a longitudinal sectional view of the sensing sensor 2 assembled, and FIG. 7 is a block diagram showing the configuration of the sensing device 1.

In the figure, reference numeral 3 denotes a wiring board. This wiring board 3 has a shape extending in the length direction (X-axis direction), and the other end side in the length direction is the insertion port 17 of the oscillation circuit unit 12. The insertion part 31 inserted in is formed. Further, a through hole 32 is formed in the wiring board 3, and the through hole 32 is closed by a bottom surface 221 of a lower case body 22, which will be described later, which is a storage member. The through hole 32 and the bottom surface 221 of the lower case body 22 form a recess that opens on one surface side (front surface side) of the wiring board 3.
Three wirings 34, 35, and 36 are provided on the surface of the wiring board 3 so as to extend from the vicinity of the outer edge of the through hole 32 toward the insertion portion 31, and both ends of the wirings 34 to 36 are respectively connected to the wiring board 3. Terminal portions 341, 351, 361 and connection terminals 342, 352, 362 are formed. A through hole 33 is formed in the wiring board 3.

  The wiring substrate 3 is provided with a crystal resonator 4 that forms a piezoelectric resonator so as to close the through hole 32 from one side. The crystal piece 41 of the crystal unit 4 is formed in a circular shape, for example, and excitation electrodes 42 and 43 are formed on the front side and the back side of the crystal unit 4, respectively. As shown in FIG. 3, the front surface side excitation electrode 42 is formed in, for example, a substantially U shape, and the back surface side excitation electrode 43 includes two excitation electrodes 431 and 432 provided in parallel to each other. The surface-side excitation electrode 42 and the excitation electrodes 431 and 432 are formed so as to face each other with the crystal piece 41 interposed therebetween, and the surface-side excitation electrode 42 is provided with a common extraction electrode 44. The tip end side of the electrode 44 is routed around the back surface of the crystal piece 41 as shown in FIG. Further, as shown in FIG. 4, extraction electrodes 441 and 442 are connected to the excitation electrodes 431 and 432 on the back surface side, respectively.

  Further, in the excitation electrode 42 on the surface side, if each region facing the excitation electrodes 431 and 432 is referred to as the excitation electrodes 421 and 422 for convenience, the surface of the excitation electrode 421 is covered with a sensing object as shown in FIG. An adsorption film 451 composed of an antibody that selectively binds to a certain influenza virus is provided. On the other hand, on the surface of the excitation electrode 422, an inhibition film 452 that inhibits the binding between the influenza virus and the excitation electrode 422 is provided. Thus, the crystal piece 41 and the excitation electrodes 421 and 431 constitute the first crystal oscillator 4A, and the crystal piece 41 and the excitation electrodes 422 and 432 constitute the second crystal oscillator 4B. These crystal resonators 4A and 4B are provided such that the extraction electrode 44 overlaps the wiring 351 of the wiring board 3 and the extraction electrodes 441 and 442 overlap the wirings 361 and 341 of the wiring board 3, respectively. With this arrangement, the thickness of each electrode of the crystal unit 4 and each wiring of the wiring board 3 is extremely small. Therefore, the peripheral portion of the crystal unit 4 is in contact with the wiring board 3, and the crystal unit 4 is connected to the wiring board 3. Are provided in a substantially horizontal state.

  Returning to FIG. 3, a flow path forming member 5 is provided on one surface side of the wiring board 3 so as to sandwich the crystal resonator 4. The flow path forming member 5 is a plate-like member, and is formed so as to expose the other end side portion constituting the insertion portion 31 of the wiring substrate 3 and cover the one end portion side where the crystal resonator 4 is provided. The flow path forming member 5 is made of, for example, a synthetic resin having a high self-adsorption property such as PDMS (polydimethylsiloxane). The flow path forming member 5 is adsorbed to the wiring board 3 as shown in FIG. 6 in a state in which, for example, plasma cleaning is performed to activate the surface and remove organic substances on the surface.

  On the back surface side of the flow path forming member 5, as shown in FIG. 4, a recess 51 is provided along these external shapes so that the crystal resonator 4 and the wires 34 to 36 are accommodated. In the concave portion 51, through holes 52 and 53 that penetrate in the thickness direction of the flow path forming member 5 are formed at positions overlapping the crystal resonator 4. A frame portion 54 surrounding these through holes 52 and 53 is provided so as to protrude downward. The frame portion 54 is provided so as to surround the excitation electrode 42, and through holes 52 and 53 are arranged in the vicinity of one end side and the other end side in the length direction of the excitation electrode 42, respectively. A region surrounded by the frame portion 54 forms a flow path 57, the flow path 57 has a horizontal ceiling surface, and the lower surface of the flow path 57 is constituted by the crystal unit 4.

  As shown in FIG. 6, the flow path 57 is configured such that the height H (flow path height dimension) is, for example, 300 μm when the upper cover body 21 is fitted to the lower case body 22. . The excitation electrodes 421 (431) and 422 (432) are provided symmetrically with respect to a line connecting the through hole 52 and the through hole 53 as shown in FIG. A through hole 58 is formed in the flow path forming member 5 at a position corresponding to the through hole 33 of the wiring board 3. In addition to the PDMS, the flow path forming member 5 is made of a material having a hardness of 20 to 60 or less and a hardness higher than that of the buffer member 6 described later, such as a synthetic resin such as acrylic resin or crystal. Can do.

  Returning to FIG. 3, the through holes 52 and 53 are detachably provided with an inlet side capillary member 55 and an outlet side capillary member 56 each made of a porous capillary member. The inlet side capillary member 55 is formed in, for example, a cylindrical shape, and the outlet side capillary member 56 is formed in, for example, a shape obtained by bending a column into a substantially L shape, and is formed of, for example, a chemical fiber bundle of polyvinyl alcohol (PVA). The inlet side capillary member 55 and the outlet side capillary member 56 may be made of a porous material such as cellulose or a hydrophilic porous resin. The inlet side capillary member 55 closes the through hole 52 of the flow path forming member 5, the upper end side thereof is exposed to the liquid receiving portion 23 of the upper cover body 21 described later, and the lower end side thereof is in the flow path 57 of the flow path forming member 5. It is provided to enter.

  The outlet side capillary member 56 is formed in a substantially L shape having a horizontal portion 561 and a vertical portion 562 extending downward from the horizontal portion 561. The vertical portion 562 closes the through hole 53 of the flow path forming member 5, and the lower end thereof enters the flow path 57 of the flow path forming member 5, and the horizontal portion 561 is connected to a waste liquid passage 59 described later. Further, as shown in FIGS. 5 and 6, the lower end surface 563 of the outlet side capillary member 56 is formed so as to be inclined upward in a horizontal plane, for example. The pores between the fibers of the inlet side capillary member 55 (holes of the porous capillary member) correspond to the sample solution inlet.

  The waste liquid channel 59 is formed in a tubular shape with, for example, hydrophilic glass, and is provided above the channel forming member 5 so as to extend along the length direction (X direction in the drawing) of the sensing sensor 2. The lower end side of the horizontal portion 561 of the outlet side capillary member 56 is provided so as to enter the inside of the waste liquid channel 59.

  As shown in FIGS. 3, 5, and 6, a waste liquid absorber 7 for absorbing and storing the sample liquid is provided on the downstream side of the waste liquid channel 59. The waste liquid absorption unit 7 includes a capillary sheet 71 that forms a capillary member, and an absorption member 72 that is provided so as to be in contact with the capillary sheet 71 and absorbs the sample liquid flowing through the capillary sheet 71. The capillary member is made of a material that causes a capillary phenomenon, and is made of, for example, a nonwoven fabric, paper, cellulose, cotton, a porous chemical fiber bundle, a hydrophilic porous resin, or the like. Further, the capillary sheet 71 is configured by forming a capillary member into a sheet shape. For example, when viewed in a plan view, the capillary sheet 71 is configured such that one end side is narrower than the other end side, and the apex 711 extends from the downstream end of the waste liquid channel 59. It is provided so as to enter the waste liquid flow path 59. Therefore, the downstream end of the waste liquid channel 59 is open.

  The lower surface of the capillary sheet 71 is provided in contact with the upper surface of the absorbing member 72. The absorbing member 72 is capable of absorbing a larger amount of liquid than can be absorbed by the capillary sheet 71, and is composed of, for example, a porous body such as sponge made of PVA or a hydrophilic material, or a cotton-like body. Yes.

  As shown in FIGS. 5 and 6, the waste liquid absorbing portion 7 is housed in a case body 73 to prevent liquid leakage, and the side wall of the case body 73 on the side of the waste liquid flow path 59 is shown in FIG. Thus, for example, a notch 74 for securing an installation area of the waste liquid flow path 59 is formed. The waste liquid channel 59 is supported by the support member 75 in a state where the height and the position in the left-right direction are positioned.

  A buffer member 6 is provided on the other surface side of the wiring board 3 described above (the side opposite to the crystal resonator 4 side). The buffer member 6 is formed of a material having a lower hardness (softer) than the flow path forming member 5 described above. As the material of the buffer member 6, a material such as silicon rubber having a hardness of 5 to 20 and a hardness lower than that of the flow path forming member 5 is selected. The buffer member 6 is designed to have a dimension that fits into a recess 24 provided on the inner side of the lower case body 22 and on the other end side in the length direction. Examples of each dimension are shown in FIG. The length R1 is 16 mm, the width R2 is 11 mm, and the overall thickness R3 is 1 mm, which is a thickness smaller than the channel height dimension H of the channel 57 formed by the channel forming member 5 described above. The thickness R4 of the portion protruding from the lower case body 22 shown in FIG.

  An upper cover body 21 is provided on one surface side of the flow path forming member 5. The upper cover body 21 is made of a resin such as plastic, for example, and is formed so as to cover the flow path forming member 5, the waste liquid flow path 59, the waste liquid absorbing portion 7, and the like. On the other hand, a lower case body 22 is provided on the other surface side of the wiring board. By fitting and pressing the upper cover body 21 to the lower case body 22, the crystal unit 4 allows the through-hole 32 to be formed. While being fixed to the wiring board 3 so as to be closed, the through hole 32 is closed by the buffer member 6, and the buffer member 6 is pressed against the lower case body 22 and fitted into the recess 24. Further, a projection (not shown) enters the through hole 33 of the wiring board 3 and the through hole 58 of the flow path forming member 5 shown in FIG. 3, thereby suppressing the displacement of the flow path forming member 5 in the lateral direction. It is configured as follows. Further, claws 26 are provided at the lower part inside the upper cover body 21, for example, two places each on the lower part of the side surface in the length direction, for a total of four places, and the lower case body 22 shown in FIG. 2 and FIG. It is configured to fit into the recess 25. FIG. 6 is a longitudinal sectional view showing a state in which the upper cover body 21 is fitted to the lower case body 22 and the detection sensor 2 is formed.

An opening configured as a liquid receiving portion 23 is formed on the upper surface side of the upper cover body 21, and the through hole 52 is opened in the opening, and the liquid supplied from the liquid receiving portion 23 is on the inlet side. The liquid is supplied to the liquid flow path 57 through the pores between the fibers of the capillary member 55 (pores of the porous capillary member). The upper cover body 21 is formed with a vent hole (not shown). When a liquid flows through the sensing sensor 2, the gas in each flow path is vented from the opening on the lower end side of the waste liquid flow path 59. It is pushed out of the sensor 2 through the mouth.
In the sensor 2 configured as described above, each electrode of the crystal unit 4 is electrically connected to the oscillation circuits 811 and 812 when the insertion portion 31 of the wiring board 3 is inserted into the insertion port 17 of the oscillation circuit unit 12. Connected.

  Subsequently, each unit provided in the arithmetic device 13 constituting the sensing device 1 will be described with reference to FIG. A switch unit 82 is provided in the subsequent stage of the oscillation circuits 811 and 812, and the frequency signal from the two oscillation circuits 811 and 812 is time-divided into the subsequent stage by the switch unit 82, and the oscillation frequency of each vibration region Can be obtained in parallel. If the output from the first oscillation circuit 811 is channel 1 and the output from the second oscillation circuit 812 is channel 2, for example, 1 second is divided into n (n is an even number), and the oscillation frequency of each channel is 1 / n. Since the frequency is acquired at least once per second by sequentially obtaining the processing in seconds, the frequency of each channel can be acquired substantially simultaneously.

  A measurement circuit unit 83 is provided following the switch unit 82. The measurement circuit unit 83 digitally processes a frequency signal that is an input signal, and measures the oscillation frequency of each channel. In the following, the outputs of channels 1 and 2 are denoted as F1 and F2, respectively. The arithmetic unit 13 includes a data bus 80, to which the CPU 84, storage means for storing a data processing program 85, a memory 86, and the above-described measurement circuit unit 83 are connected. Furthermore, the display unit 16 and the input means 87 such as a keyboard are connected to the data bus 80.

  The data processing program 85 acquires the time series data of the oscillation frequency F1 and the time series data of the oscillation frequency F2 based on the signal output from the measurement circuit unit 83 and stores it in the memory 86. Simultaneously with this data acquisition operation, the difference “F1-F2” of the time series data of the oscillation frequency F1 acquired from the channel 1 and the oscillation frequency F2 acquired from the channel 2 in the same time zone is calculated. The time series data of the data is acquired and stored in the memory 86, and the graph of “F1-F2” is displayed on the display unit 16.

  Next, a process for configuring the detection sensor 2 will be described. As shown in FIG. 2 and FIG. 3, after each component is arranged inside the lower case body 22, the upper cover body 21 is covered with the lower case body 22, and the claw 26 inside the upper cover body 21 is lowered. The upper cover body 21 is pressed against the lower case body 22 until it fits into the recess 25 on the side surface of the side case body 22. In this process, the flow path forming member 5 inside the lower case body 22 presses the wiring board 3, and the buffer member 6 contracts in the height direction by the pressure from the wiring board 3. At this time, since the buffer member 6 is fitted in the recess 24 inside the lower case body 22, the buffer member 6 can be prevented from jumping out from the lower case body 22.

  The thickness R3 of the buffer member 6 is set such that the thickness R4 protruding from the lower case body 22 of the buffer member 6 becomes 0 when the claw 26 of the upper cover body 21 is fitted in the recess 25 of the lower case body 22. It is designed in advance not to be. For this reason, even after the upper cover body 21 and the lower case body 22 are fitted together, the buffer member 6 can absorb an excessive pressure component in the pressure caused by the fitting.

  Next, a process of determining the presence or absence of influenza virus in the sample solution using the detection sensor 2 will be described with reference to FIG. However, these FIG. 8 shows the image of the liquid (sample solution, buffer solution) flowing through the detection sensor 2, and is drawn exaggerated from the actual state. First, the detection sensor 2 is connected to the oscillation unit 12, and using an injector (not shown), as shown in FIG. Here, the flow of the liquid in the detection sensor 2 when the liquid is supplied to the detection sensor 2 will be described. The liquid is absorbed by the inlet side capillary member 55 by capillary action, flows through the capillary member 55, flows into the flow path 57, and is supplied to the surface on the one end side of the crystal unit 4.

  Since the surface of the crystal piece 41 constituting the crystal resonator 4 is hydrophilic, the inside of the flow channel 57 is wet and spreads, and the liquid in the inlet side capillary member 55 following the liquid spread in the flow channel 57 is crystallized due to surface tension. The liquid is drawn out to the surface of the piece 41 and continuously flows from the liquid receiving portion 23 to the flow path 57. When the liquid on the surface of the crystal unit 4 reaches the outlet-side capillary member 56, the liquid is absorbed by the outlet-side capillary member 56 by capillary action, flows through the capillary member 56, and oozes out into the waste liquid channel 59. Here, in addition to the capillary phenomenon, the siphon principle works, and the liquid in the liquid receiving portion 23 automatically passes through the surface of the crystal unit 4 and is discharged to the waste liquid channel 59.

  The liquid in the waste liquid flow path 59 flows downstream in the waste liquid flow path 59 and reaches the capillary sheet 71. When the liquid in the waste liquid channel 59 reaches the capillary sheet 71, the liquid moves to the capillary sheet 71 side at a speed higher than the moving speed of the liquid flowing through the waste liquid channel 59. When the liquid comes into contact with the capillary sheet 71, the liquid is quickly absorbed on the capillary sheet 71 side, and flows through the capillary sheet 71 so as to spread by the capillary phenomenon. As shown in FIG. A state in which the liquid is interrupted in 59 is formed.

  When the liquid is divided in the waste liquid flow path 59 in this way, the liquid on the capillary sheet 71 side is absorbed and stored in the absorbing member 72 that contacts the capillary sheet 71. On the other hand, the liquid remaining in the liquid receiving portion 23 tends to flow toward the waste liquid flow path 59 based on the capillary phenomenon and the principle of siphon. And contact with the capillary sheet 71 again as shown in FIG. In this way, the division of the liquid in the waste liquid flow path 59 and the flow of the liquid in the waste liquid flow path 59 are repeated, and when all of the liquid in the liquid receiving portion 23 has flowed, FIG. As shown, the liquid is stopped in the waste liquid channel 59 in a state where the liquid is divided.

  When the theory is returned to the supply of the buffer solution, the buffer solution dropped on the liquid receiving portion 23 flows through the sensing sensor 2 as described above. When the buffer solution flowing through the flow path 57 is supplied to the surfaces of the excitation electrodes 421 and 422, the excitation electrodes 421 and 422 are formed symmetrically when viewed from the inlet side to the outlet side of the flow path 57. Equally affected by water pressure. As a result, the oscillation frequencies F1 and F2 of the first crystal unit 4A and the second crystal unit 4B are equally reduced.

  Subsequently, the same amount of sample solution as the buffer solution is supplied to the liquid receiving unit 23. As a result, the pressure applied to the buffer solution absorbed by the inlet side capillary member 55 is increased, and the buffer solution again flows toward the downstream side in the waste liquid channel 59 as in FIG. 8, and the sample solution flows into the inlet side capillary tube. Absorbed by the member 55. The absorbed sample solution flows into the flow channel 57 from the inlet side capillary member 55 in the same manner as the buffer solution, and the inside of the flow channel 57 is replaced with the sample solution from the buffer solution.

  Also at this time, since the excitation electrodes 421 and 422 are formed symmetrically when viewed from the inlet side to the outlet side of the flow path 57, these electrodes 421 and 422 are subject to pressure changes due to switching of the liquid in the flow path 57. Evenly received, the oscillation frequencies of the first crystal unit 4A and the second crystal unit 4B due to the pressure change are aligned with each other and change. When influenza virus, which is a measurement object, is contained in the sample solution, the influenza virus is adsorbed on the adsorption film 451 on the excitation electrode 421, while the influenza virus is not adsorbed on the inhibition film 452 on the excitation electrode 422. . For this reason, the frequency F1 falls and F1-F2 changes according to the amount of influenza virus adsorbed to the adsorption film 451. Thus, the presence or absence of influenza virus can be determined based on the change in F1-F2. Further, a relational expression between the change amount of the oscillation frequency difference F1-F2 and the concentration of the sensing object in the sample liquid is acquired in advance, and the change amount of the difference between the oscillation frequency obtained by the relational expression and the measurement is obtained. From the above, the concentration of the sensing object in the sample solution may be obtained.

  In the sensing sensor 2 of the above-described embodiment, the buffer member 6 is provided on the other surface side of the wiring board 3. As described above, the buffer member 6 is formed of a softer material (having a lower hardness) than the flow path forming member 5. For this reason, when the upper cover body 21 and the lower case body 22 are fitted and the flow path 57 is formed by the pressure, an excessive pressure component is absorbed by the buffer member 6. Therefore, it is possible to prevent the flow path 57 from being crushed by an excessive pressure component or the crystal resonator 4 from being lost. Therefore, it is possible to set the flow channel height dimension H to be narrow in advance, for example, 300 μm or less, while maintaining the height H (flow channel height dimension) of the flow channel 57 in a uniform state. Thus, when the flow path height dimension H is set to be narrow, the contact rate between the influenza virus, which is the sensing object, and the adsorption film 451 provided on the crystal unit 4 can be improved. As a result, the sensitivity to the sensing object can be increased as the entire sensing sensor 2.

  Furthermore, in this detection sensor 2, the sample liquid flows from the inlet to the other end side of the excitation electrode 42 via the flow channel 57 on the one surface side of the crystal unit 4 by capillary action, and is contained in the sample liquid. The sensing object to be detected is adsorbed by the adsorption film 451 provided on the crystal unit 4. Therefore, since it is not necessary to provide a device such as a pump for circulating the sample solution, the apparatus can be prevented from being enlarged and complicated, and the measurement can be performed easily.

  The sample liquid is stored in the absorption member 72 via a waste liquid channel 59 and a capillary member provided on the downstream side of the channel 57. The capillary member is provided so as to come into contact with the sample liquid in the waste liquid flow path 59, and when the sample liquid in the waste liquid flow path 59 reaches the capillary member, the capillary member causes the speed to be higher than the moving speed of the sample liquid. Move as if pulled. Accordingly, a state in which a gap is generated between the capillary member and the sample liquid in the waste liquid channel 59 is formed. As a result, the capillary member of the waste liquid absorption unit 7 and the flow path 57 in which the sample liquid is stored are separated from each other, and the occurrence of the phenomenon that the sample liquid in the flow path 57 is diluted with the buffer solution is suppressed. Therefore, it is possible to detect or quantify the sensing object in the sample liquid in a state where the measurement sensitivity is always high.

  Further, as described above, the sample liquid is finally divided in the waste liquid flow path 59 and the waste liquid absorption part 7 and the flow path 57 are separated from each other. It will be surely stationary. Therefore, measurement can be continued until the antigen-antibody reaction between the sample solution and the adsorption film 451 is saturated, and more accurate measurement can be performed.

  As shown in FIG. 9A, the detection sensor 2 according to the present embodiment may have a configuration in which the capillary sheet 74 is provided so that the downstream end of the waste liquid channel 59 is closed with the capillary sheet 74. Even with this configuration, a gap can be formed between the capillary sheet 74 and the sample liquid in the waste liquid channel 59. Furthermore, since a porous body such as sponge or a cotton-like body is provided as the absorbent member 72, the amount of liquid stored can be easily changed by changing the material and size compared to the case where the absorbent member 72 is not provided. Thus, the design of the sensor 2 is facilitated.

  The capillary member is not necessarily formed into a sheet shape as long as a gap is formed between the capillary member and the sample liquid in the waste liquid channel 59. Furthermore, in the sensing sensor 2 shown in FIGS. 2 to 6, the capillary sheet 71 has a shape in which one end side is narrower than the other end side in plan view, and the one end side enters the waste liquid channel 59. It is preferred that The capillary sheet 71 does not necessarily have a sharp shape at one end side. Further, the capacity of the capillary member that enters the waste liquid channel 59 is also appropriately selected.

Further, the capillary member and the absorbing member 72 only need to have a larger amount of liquid that can be absorbed by the absorbing member 72 than the amount of liquid that can be absorbed by the capillary member. Furthermore, as shown in FIG. 9B, a waste liquid region 76 may be formed on the lower side of the absorbing member 721, and the liquid dropped from the absorbing member 721 by its own weight may be stored in the waste liquid region 76. In FIG. 9B, 50 is a waste liquid flow path, 564 is an outlet side capillary member, and 77 is a case body.
As described above, the waste liquid flow path 59 (50) may be configured to circulate liquid by capillary action, and is not limited to a glass tube but may be a flow path formed by a flow path forming member.

  Further, in the detection of a sensing object using the sensing sensor 2 of the present invention, a supply liquid containing a sensitizing material that binds to the sensing object adsorbed on the adsorption film 451 after the sample liquid is supplied to the sensing sensor 2. (Sensitization liquid) can be supplied, and further sensitization is performed by supplying a sensitizing liquid containing a sensitizing material that overlaps and binds to the sensitizing material bonded to the sensing object. be able to. Even when such a sensitizing solution is used, when the sensitizing solution is supplied to the flow path 57, mixing with the previously supplied solution is prevented, so that dilution of the sensitizing solution can be prevented. . Therefore, since the sensitizer is quickly bonded, the measurement sensitivity can be increased and the measurement time can be shortened.

  Furthermore, the crystal resonators 4A and 4B may be constituted by divided crystal pieces, and the crystal pieces may be arranged very close to each other. Furthermore, it is not always necessary to provide the first crystal unit 4A and the second crystal unit 4B, and one crystal unit provided with an adsorption film may be provided. In this case, since the oscillation frequency changes when the sensing object is adsorbed to the adsorption film, for example, a threshold value is set in advance, and whether or not the sensing object is detected is determined depending on whether the oscillation frequency exceeds the threshold value. judge.

  Furthermore, instead of arranging the buffer member 6 on the other surface side of the wiring board 3, the buffer member 6 may be arranged between the flow path forming member 5 and the upper cover body 21, and in this case also, the upper cover body is arranged. It is possible for the buffer member 6 to absorb an excessive pressure component in the pressure caused by the fitting between the lower case body 22 and the lower case body 22. Therefore, the same effect as the above-described embodiment can be obtained.

  A sensing sensor 20 in which the buffer member 6 according to the present invention is applied to the conventional sensing sensor of FIG. 12 is shown in FIG. In addition, the same code | symbol is attached | subjected to the site | part similar to the sensor 2 mentioned above, and description is abbreviate | omitted. The detection sensor 20 has a configuration in which the waste liquid absorber 7 is omitted from the detection sensor 2. In the detection sensor 20, the liquid supplied from the liquid receiver 23 flows into the flow path 57 from the capillary member 550 by the capillary phenomenon in the same manner as the detection sensor 2, and into the waste liquid flow path 590 through the capillary member 560. And discharged.

  Also in the detection sensor 20, the flow path 57 is formed by fitting the upper cover body 21 to the lower case body 22 and pressing the flow path forming member 5 against the wiring board 3. At this time, the buffer member 6 is disposed on the other surface side of the wiring board 3, so that the entire buffer member 6 absorbs an excessive pressure component in the pressure caused by the fitting of the upper cover body 21 and the lower case body 22. As a result, since the flow channel 57 can be formed uniformly, the flow channel height dimension H of the flow channel 57 can be designed to be narrow.

  In the above, since the sensing sensor 2 can set the flow path 57 narrow by interposing the buffer member 6 as described above, the contact between the sensing object and the adsorption film 451 is possible. As a result, the sensitivity of the sensing sensor 2 can be increased. Furthermore, since the flow path 57 can be prevented from being crushed by the pressure from the upper cover body 21, a remarkable effect can be obtained particularly when forming a sensor having a flow path height dimension H of 300 μm or less. .

(Evaluation test)
According to the above-described embodiment, how the difference between F1 and F2 is changed using the sensing sensor 2 was examined. In this evaluation test, solutions prepared by different concentrations of C-reactive protein (CRP) were injected as sample solutions, and a CRP antibody was used as the adsorption film 451 of the sensor 2. With respect to the flow channel height dimension of the flow channel 57, a sensor formed at 300 μm and a sensor formed at 50 μm were prepared, and each sensor was tested.

  The result of the evaluation test is shown in a graph in FIG. The vertical axis represents the difference between F1 and F2, and the horizontal axis represents the concentration of CRP in the sample solution, which is logarithmic. The solid line graph shows the reaction amount in a sensor having a flow path height dimension of 50 μm, and the dotted line graph shows the reaction amount in a sensor with a flow path height dimension of 300 μm. From the graph, it is recognized that the sensitivity of the sensor having the channel height dimension of 50 μm is significantly higher than that of the sensor having the channel height dimension of 300 μm. This result is presumed to be due to an increase in the contact rate between the adsorption film and the sensing object by reducing the channel height dimension.

DESCRIPTION OF SYMBOLS 1 Sensing apparatus 2 Sensing sensor 3 Wiring board 4 Crystal oscillator 5 Flow path forming member 6 Buffer member 7 Waste liquid absorption part

Claims (4)

A wiring board having a connection terminal connected to a measuring instrument for measuring the oscillation frequency and having a recess formed on one side;
The piezoelectric piece is provided with an excitation electrode, and is fixed to the wiring board so as to close the recess and to have a vibration region facing the recess, and the excitation electrode is electrically connected to the connection terminal. A piezoelectric vibrator formed with an adsorption film that adsorbs a sensing object in the sample liquid,
A flow path forming member provided so as to cover a region on one surface side of the wiring board including the piezoelectric vibrator, and having a sample liquid inlet;
When the one surface side of the wiring board is the upper surface side, a pressing member that fixes the flow path forming member in a pressed state against the wiring board by engaging with a member positioned below the flow path forming member. When,
The sample liquid formed between the wiring board and the flow path forming member by pressing by the pressing member and distributed to the injection port flows from one end side to the other end side on one surface side of the piezoelectric vibrator. A flow path to be
A buffer member that is provided between the flow path forming member and the pressing member or on the other surface side of the wiring board and absorbs an excessive amount of pressure from the pressing member ;
The sensing sensor, wherein the flow path forming member is pressed and fixed by the pressing member even when the buffer member is not present . On the other surface side of the buffer member from the wiring board side, there is a recess having a depth smaller than the thickness of the buffer member, and a storage member into which the buffer member is fitted is provided in the recess.
The sensor according to claim 1, wherein the flow path is formed by fitting the pressing member and the storage member.   The height of the said flow path is 300 micrometers or less, The sensing sensor of Claim 1 or 2 characterized by the above-mentioned.   A sensing device comprising the sensing sensor according to claim 1 and the measuring device.

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