JP2007192650A - Qcm sensor and qcm sensor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To extremely simplify a QCM (Quartz Crystal Microbalance) sensor device for quantitatively analyzing a target material, by detecting resonance frequency of a piezoelectric vibrator varied by adsorption of an object into an adsorption film, without having to use external power by a pump or the like in making sample liquid flow. <P>SOLUTION: In this QCM sensor device, only by dropping the sample liquid into an injecting hole, the sample liquid infiltrates into a flow channel and is absorbed by an absorbing hole. At this time, the target material in the sample liquid is adsorbed to the piezoelectric vibrator having the adsorption film, and the variation of the resonance frequency of the piezoelectric vibrator is detected in that case, thereby allowing the adsorption amount of the target material to be known. A very simple QCM sensor device can be obtained, without having to use external power by a pump or the like in making sample liquid flow. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention provides an electrode pattern for excitation based on changes in electrical characteristics such as resonance frequency and impedance when the electrode pattern for excitation on a piezoelectric vibrator that vibrates at a predetermined resonance frequency is exposed to a sample gas or a sample solution. QCM (Quartz) for detecting and quantifying the components of the sample adsorbed on the surface
The present invention relates to a sensor device and a sensor.

  In recent years, chemical biosensors using a microbalance principle using a piezoelectric vibrator have attracted attention. The structure of a conventional QCM sensor device will be described with reference to FIG. FIG. 14 shows a cross-sectional structure of a conventional QCM sensor device. This sensor device has a cylindrical cell 21 made of an acrylic resin constituting a container body, and a flange portion 16 having an opening smaller than the outer diameter of the piezoelectric vibrator 1 is formed on the side wall of the cell 21. Yes. The outer periphery of the piezoelectric vibrator 1 is bonded and fixed to the lower surface of the flange portion 16 with an adhesive. Of the electrode patterns 2a and 2b provided on the excitation portion of the piezoelectric vibrator 1, the electrode pattern 2b is the flange portion. 16 is exposed to an opening formed inside. Further, a spring 18 is disposed between the piezoelectric vibrator 1 and the base 17 so that the outer peripheral portion of the piezoelectric vibrator 1 is pressed against the flange portion 16. Terminal pins 19 for pulling out electrode patterns 2a and 2b to the outside are fixed to the pedestal 17 by glass seals 20. The electrode patterns 2a and 2b of the piezoelectric vibrator 1 are respectively connected to the terminal pins 19 via springs 18. They are electrically connected (see, for example, Patent Document 1 and Patent Document 2).

  In the above QCM sensor device, only the surface on which the electrode pattern 2b of the piezoelectric vibrator 1 is formed is exposed to the sample liquid side and exposed to the sample gas or sample solution, and an adsorption film (not shown) provided on the electrode pattern 2b. Thus, the sample component can be detected and quantified from the amount of change in the resonance frequency that fluctuates due to the adsorption and desorption of the sample component.

Further, the QCM sensor device is provided with a stirring unit 51 for stirring the sample liquid. The stirring unit 51 is attached to the support unit 52 and is put into the sample liquid from the upper opening side of the cell 21, and moves up and down to stir the sample liquid.

As another form, a configuration has been proposed in which a cell body containing a sample liquid is placed on a rocking stirring mechanism and the cell 21 itself is rocked.
JP 2002-310872 (pages 5-8, FIG. 1, FIG. 6, FIG. 7, FIG. 8) JP 2002-277369 A (pages 4 to 6, FIG. 1, FIG. 5, FIG. 6)

  The QCM sensor device described above has the following problems.

  In the conventional QCM sensor device, when stirring the solution in the cell which is a container body, a mechanism for shaking the cell itself or a mechanism for immersing the stirring part in the solution in the cell and moving it up and down is proposed. However, in the method of shaking the cell itself, stirring is not sufficient, the encounter probability of a substance to be detected with respect to the QCM sensor is lowered, and it is difficult to obtain a QCM sensor device having stable performance.

  On the other hand, the mechanism for stirring the sample liquid by moving the stirring unit up and down can sufficiently stir the sample liquid, but it is special so that the sample can quickly go to the piezoelectric vibrator 1 below the stirring unit 51. It is necessary to provide a sample supply path, and the apparatus is complicated.

  For this reason, when the sample is supplied to the liquid surface, it takes time to uniformly stir, and the measurement time is long. Also, depending on the measurement, the temperature of the sample liquid needs to be constant. However, in the stirring mechanism as described above, the portion of the handle to which the stirring unit 51 is attached touches both the sample liquid and air. There was a problem that the temperature of the liquid became unstable.

  According to the present invention, a piezoelectric vibrator having an adsorption film and an excitation electrode for selectively adsorbing a target substance is brought into contact with a sample liquid, and the resonance frequency of the piezoelectric vibrator changes when the object is adsorbed on the adsorption film. In the QCM sensor device that detects the target substance and quantitatively analyzes the target substance, it is not necessary to use any external power such as a pump at the time of flowing the sample liquid, and the object is to provide a very simple QCM sensor device .

  In order to achieve the above object, the structure described below is adopted for the mounting structure of the piezoelectric vibrator in the present invention.

The QCM sensor of the present invention is a QCM sensor having an adsorption film for selectively adsorbing a target substance, a piezoelectric vibrator having an excitation electrode, and an external connection electrode electrically connected to the excitation electrode,
It is characterized by having a substrate provided with a recess for flowing the sample liquid, an injection hole for injecting the sample liquid, and a cover provided with an absorption hole for absorbing the injected sample liquid.

The QCM sensor of the present invention is a QCM sensor having an adsorption film for selectively adsorbing a target substance, a piezoelectric vibrator having an excitation electrode, and an external connection electrode electrically connected to the excitation electrode,
A cover for providing a substrate for flowing the sample liquid, an injection hole for injecting the sample liquid, a recess serving as a flow path for the sample liquid, and an absorption hole for absorbing the injected sample liquid; It is characterized by.

In the QCM sensor device of the present invention, a piezoelectric vibrator having an adsorption film and an excitation electrode for selectively adsorbing a target substance is brought into contact with a sample liquid, and the piezoelectric vibration that changes when the target substance is adsorbed on the adsorption film. A QCM sensor device for quantitatively analyzing a target substance by detecting a resonance frequency of a child,
A substrate provided with a recess for flowing a sample liquid, a cover provided with an injection hole for injecting the sample liquid, an absorption hole for absorbing the injected sample liquid, and an excitation electrode electrically connected A QCM sensor having an external connection electrode, and an analyzer for quantitatively analyzing a target substance in response to a signal from the external connection electrode of the QCM sensor.

In the QCM sensor device of the present invention, a piezoelectric vibrator having an adsorption film and an excitation electrode for selectively adsorbing a target substance is brought into contact with a sample liquid, and the piezoelectric vibration that changes when the target substance is adsorbed on the adsorption film. A QCM sensor device for quantitatively analyzing a target substance by detecting a resonance frequency of a child,
A substrate provided with a substrate for flowing the sample liquid, an injection hole for injecting the sample liquid, an absorption hole for absorbing the injected sample liquid, and a recess for flowing the sample liquid; It has a QCM sensor having an external connection electrode electrically connected to the excitation electrode, and an analyzer for quantitatively analyzing a target substance in response to a signal from the external connection electrode of the QCM sensor.

  The QCM sensor device and the QCM sensor of the present invention are the QCM sensor device and the QCM sensor described above, and it is preferable that an absorbing member is disposed in a recess provided in a substrate or a cover.

  In the QCM sensor device of the present invention, a piezoelectric vibrator having an adsorption film and an excitation electrode for selectively adsorbing a target substance is brought into contact with a sample liquid, and the piezoelectric vibration that changes when the object is adsorbed on the adsorption film. A QCM sensor device for quantitatively analyzing a target substance by detecting a resonance frequency of a child, a substrate provided with a recess for flowing a sample liquid, and a piezoelectric vibrator disposed with a predetermined gap from the substrate; A QCM sensor having an injection hole for injecting a sample liquid, a cover provided with an absorption hole for absorbing the injected sample liquid, an external connection electrode electrically connected to the excitation electrode, and a QCM And an analyzer that quantitatively analyzes the target substance in response to a signal from the external connection electrode of the sensor. With this structure, the sample liquid injected from the injection hole is separated from the substrate. Since flows concentrated in the gap formed by the chromatography, the objective substance in the sample liquid opportunity to encounter adsorbed film provided on the piezoelectric vibrator at a high probability increases.

  Furthermore, since the sample liquid is gradually absorbed from the gap by the absorption hole, finally, almost all the sample liquid can be made to encounter the adsorption film of the piezoelectric vibrator. As a result, the target substance in the sample liquid is adsorbed to the piezoelectric vibrator provided with the adsorption film, and the amount of the target substance adsorbed can be known by detecting the change in the resonance frequency of the piezoelectric vibrator. In addition, the sensor alone does not require any external power such as a pump to flow the sample liquid, and the sensor alone can be disposable, so that a very simple QCM sensor device and sensor can be obtained.

  A QCM sensor device according to an optimal embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a QCM sensor mounting structure according to an embodiment of the present invention, and is a cross-sectional view taken along line A-A ′ in FIG. 13. 12 is a cross-sectional view of a QCM sensor according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of the piezoelectric vibrator 1, FIG. 3 is a perspective view of the piezoelectric vibrator 1, and FIGS. FIG. 8 is a cross-sectional view showing a state in which the substrate 3 on which the piezoelectric vibrator 1 is mounted, and a state in which the piezoelectric vibrator 1 is mounted on the substrate 3. FIG. FIG. 9 is a plan view showing the position of the sealing material applied on the substrate 3, FIGS. 10 and 11 are a perspective view and a sectional view showing the cover 7, and FIG. A cross-sectional view of the QCM sensor when the absorbing member 12 is disposed, and FIG. 13 is an external view showing the QCM sensor device according to the embodiment of the present invention.

  First, a single QCM sensor used in the QCM sensor device of this embodiment will be described. As shown in FIG. 1, a piezoelectric vibrator 1 having an adsorption film (not shown) for selectively adsorbing a target substance and an excitation electrode is brought into contact with a sample liquid, and the object is adsorbed on the adsorption film. The QCM sensor that detects the resonance frequency of the piezoelectric vibrator 1 that changes by performing quantitative analysis of the target substance includes a piezoelectric vibrator having an adsorption film and an excitation electrode for selectively adsorbing the target substance. A QCM sensor device for contacting the sample liquid and detecting the resonance frequency of the piezoelectric vibrator that changes as the target object is adsorbed on the adsorption film to quantitatively analyze the target substance, and flowing the sample liquid The substrate 3 provided with the recess 10 for the above, the piezoelectric vibrator 1 disposed using the connecting material and the sealing material 6 while maintaining a predetermined gap with the substrate 3, and the sample liquid is injected into the gap. Injection hole 8 , And a cover 7 provided with the absorption holes 9 for absorbing the sample liquid injected into the gap, and the sealing material 6 for bonding the substrate 3 and the cover 7.

  Next, the manufacturing process of the QCM sensor in this embodiment will be described with reference to FIGS. First, as shown in FIG. 2, a piezoelectric vibrator 1 made of a quartz plate is formed into an arbitrary size by a method such as etching or dicing, and a metal thin film is formed on the quartz plate by a sputtering method or a vacuum evaporation method using a metal mask. As a result, the electrode patterns 2a and 2b for excitation are formed on the piezoelectric vibrator 1.

  FIG. 3 is a perspective view of the piezoelectric vibrator 1, and the dotted line represents the state of the electrode pattern 2a on the back surface. Since the excitation electrode pattern 2b is electrically connected to the wiring 4b provided on the substrate 3 shown in FIG. 4 to be described later, the connection wiring is on the same surface as the excitation electrode pattern 2a. The piezoelectric vibrator 1 is formed so as to go around the side surface.

  In the present embodiment, an AT crystal plate is used as the piezoelectric vibrator 1, a 5 mm square and a 50 μm thickness is used, and a gold pattern such that the excitation electrode patterns 2a and 2b are 3 mm square is 0.00 mm. It was formed with a thickness of 2 μm.

  Next, as shown in FIG. 4, a glass epoxy substrate formed of glass fiber and epoxy resin is used for the substrate 3 on which the piezoelectric vibrator 1 is mounted. Wirings 4a and 4b are formed on one surface of the substrate 3, and are connected to the wiring on the back surface side through through holes. In the present embodiment, a substrate 3 having a thickness of 0.5 mm is used, and the wirings 4a and 4b and the through holes have a three-layer structure of copper, nickel and gold.

  Further, the substrate 3 is provided with a concave portion 10 as shown in FIG. The recess 10 is formed by applying a photosensitive resin on the substrate 3 and removing the photosensitive resin in a portion that becomes a flow path by exposure and development, or by using a plastic film having an opening in the recess as an adhesive or adhesive. It is formed by the method of pasting with.

  As shown in FIG. 11, the concave portion 10 formed at this time can be obtained on the cover 7 side instead of the substrate 3 side, and the same effect can be obtained.

  Next, as shown in FIG. 6, the electrode patterns 2a and 2b for excitation provided on the piezoelectric vibrator 1 and the wirings 4a and 4b provided on the substrate 3 are connected by a conductive adhesive or an anisotropic conductive sheet. Electrical connection is made using material 5.

  In this embodiment, a conductive adhesive containing conductive particles such as silver and palladium in a silicone adhesive is used as the connection material 5, which is applied onto the wirings 4 a and 4 b of the substrate 3 with a dispenser, and piezoelectric vibration is applied. The electrode patterns 2a and 2b for exciting the child 1 and the wirings 4a and 4b were aligned, the conductive adhesive was cured by heat treatment, and electrical connection was performed.

  Further, as shown in FIG. 7, a sealing material 6 such as epoxy, silicone, or polyurethane is applied to the outer peripheral portion of the piezoelectric vibrator 1 using a dispenser, and the sealing material 6 is cured, whereby the piezoelectric vibrator 1. And the substrate 3 are hermetically sealed.

  In this embodiment, a room temperature curing type silicone adhesive that is soft after curing and does not generate stress that deforms the piezoelectric vibrator 1 is used as the sealing material 6.

  An adsorption film (not shown) for adsorbing a specific substance is formed on the electrode pattern 2b portion of the piezoelectric vibrator 1 mounted on the substrate 3. This adsorption film is formed by applying and drying an antibody or the like according to the substance to be adsorbed.

  Next, as shown in FIG. 8, which is a cross-sectional view taken along the line BB ′ of FIG. 13, the substrate 3 on which the piezoelectric vibrator 1 is mounted and the cover 7 are bonded to each other by using a sealing material. The provided concave portion 10 remains as a gap, and a flow path through which the sample liquid flows can be provided. As the sealing material applied to the substrate 3 side, the same room temperature curing type silicone adhesive as that applied to the outer peripheral portion of the piezoelectric vibrator 1 is used, and the outer periphery of the concave portion 10 formed on the substrate 3 as shown in FIG. The flow path is formed by coating the substrate 3 and the cover 7 together.

  At this time, the height h of the gap is determined by the depth of the concave portion 10 provided on the substrate 3, and can be freely changed within a range in which the sample liquid can pass. In the present embodiment, the depth of the concave portion provided in the substrate is set to 100 μm so that the height h is about 30 μm, but is not particularly limited. Although there is no restriction | limiting in particular in the material as the cover 7, The acrylic board which provided the injection hole 8 and the absorption hole 9 as shown in FIG. 10 was used in this embodiment.

  The injection hole 8 and the absorption hole 9 provided in the cover 7 are formed by forming a hole with a diameter of about 5 mm in the case of the injection hole 8 and cutting a hole with a diameter of about 0.2 mm with a drill in the case of the absorption hole 9. As for the number of the absorption holes 9, an appropriate number is provided depending on the amount of the sample liquid.

  Further, as shown in FIG. 11, the same effect can be obtained even if the concave portion 10 provided in the substrate 3 is formed not on the substrate 3 side but on the cover 7 side.

  By performing the above steps, a flow path type QCM sensor as shown in FIG. 1 is completed. The structure of this QCM sensor is mainly composed of the piezoelectric vibrator 1, the substrate 3, and the cover 7, and has a very simple structure. Furthermore, it is possible to flow the sample liquid through the flow path in which the piezoelectric vibrator 1 is arranged without using any external power such as a pump, and thereby the target substance in the sample liquid is provided to the piezoelectric vibrator 1 provided with the adsorption film. The amount of adsorption of the target substance can be known by detecting the change in the resonance frequency of the piezoelectric vibrator 1 at that time.

  In addition, as shown in FIG. 12, the absorption member 12 is disposed in the QCM sensor shown above in the portion provided with the water absorption hole 9 formed in the cover 7 of the recess 10 provided on the substrate 3, so that the sample liquid is absorbed. Since the speed of soaking into the member is the flow rate of the sample liquid, it is possible to control the flow rate of the sample liquid by changing the fineness of the absorption member. In the present embodiment, a membrane filter is used as the absorbing member 12.

  FIG. 13 is an external view showing the relationship between the QCM sensor 13 and the analyzer 15. The QCM sensor 13 mainly composed of the piezoelectric vibrator 1, the substrate 3, and the cover 7 is provided with an injection hole 8 for dropping the sample liquid and an absorption hole 9 for absorbing the sample liquid. Since the wirings 4a and 4b on the substrate 3 are electrically connected to the external analyzer 15, the wirings 4a and 4b on the substrate 3 are projected out of the case cover 7, and the wirings 4a and 4b are arranged. By connecting the substrate 3 thus formed to a predetermined connector portion of the analyzer 15, the analyzer 15 performs analysis and measurement.

  With the above structure, just by dropping the sample liquid into the injection hole 8, the sample liquid enters the flow path and is absorbed by the absorption hole 9. At this time, the target substance in the sample liquid is adsorbed to the piezoelectric vibrator 1 provided with the adsorption film, and the amount of adsorption of the target substance can be known by detecting the change in the resonance frequency of the piezoelectric vibrator 1 at that time. Become. It is not necessary to use any external power such as a pump when flowing the sample liquid, and a very simple QCM sensor device can be obtained.

Further, as shown in FIG. 13, since the QCM sensor can be easily attached and detached by the connector of the analyzer 15, analysis of a plurality of samples can be easily performed only by exchanging the QCM sensor portion.

FIG. 14 is a cross-sectional view taken along the line A-A ′ in FIG. 13, showing the mounting structure of the QCM sensor in the embodiment of the present invention. It is sectional drawing which shows the piezoelectric vibrator of the QCM sensor in embodiment of this invention. It is a perspective view which shows the piezoelectric vibrator of the QCM sensor in embodiment of this invention. It is sectional drawing which shows the board | substrate of the QCM sensor in embodiment of this invention. It is a perspective view which shows the board | substrate of the QCM sensor in embodiment of this invention. It is sectional drawing which shows the piezoelectric vibrator and board | substrate of a QCM sensor in embodiment of this invention. It is sectional drawing which shows the piezoelectric vibrator and board | substrate of a QCM sensor in embodiment of this invention. FIG. 14 is a cross-sectional view taken along the line B-B ′ in FIG. 13, showing the mounting structure of the QCM sensor in the embodiment of the present invention. It is a top view which shows the board | substrate of the QCM sensor in embodiment of this invention. It is a perspective view which shows the cover of the QCM sensor in embodiment of this invention. It is sectional drawing which shows the cover of the QCM sensor in embodiment of this invention. It is sectional drawing which shows the mounting structure of the QCM sensor in embodiment of this invention. It is a perspective view which shows the QCM sensor apparatus in embodiment of this invention. It is sectional drawing which shows the mounting structure of the piezoelectric vibrator in a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Piezoelectric vibrator 2a, 2b Electrode pattern 3 Board | substrate 4a, 4b Wiring 5 Connection material 6 Sealing material 7 Cover 8 Injection hole 9 Absorption hole 10 Recessed part 11 Analyzing device 12 Absorbing member 13 QCM sensor 16 Flange part 17 Base 18 Spring 19 Pin 20 Glass seal 21 Cell 51 Stirring unit 52 Supporting unit

Claims (6)

A QCM sensor having a piezoelectric vibrator having an adsorption film and an excitation electrode for selectively adsorbing a target substance, and an external connection electrode electrically connected to the excitation electrode,
A QCM sensor comprising: a substrate provided with a recess for flowing the sample liquid; and a cover provided with an injection hole for injecting the sample liquid and an absorption hole for absorbing the injected sample liquid. A QCM sensor having a piezoelectric vibrator having an adsorption film and an excitation electrode for selectively adsorbing a target substance, and an external connection electrode electrically connected to the excitation electrode,
A substrate provided with a substrate for flowing the sample liquid, an injection hole for injecting the sample liquid, a recess serving as a flow path for the sample liquid, and an absorption hole for absorbing the injected sample liquid; QCM sensor with.   The QCM sensor according to claim 1, wherein an absorption member is provided in a recess provided in the substrate or the cover. A piezoelectric vibrator having an adsorption film and an excitation electrode for selectively adsorbing a target substance is brought into contact with a sample liquid, and the resonance frequency of the piezoelectric vibrator that changes when the target substance is adsorbed to the adsorption film is changed. A QCM sensor device for detecting and quantitatively analyzing the target substance,
A substrate provided with a recess for flowing the sample liquid, a cover provided with an injection hole for injecting the sample liquid and an absorption hole for absorbing the injected sample liquid, the excitation electrode and the electric QCM sensor device comprising: a QCM sensor having externally connected external connection electrodes; and an analyzer for quantitatively analyzing the target substance in response to a signal from the external connection electrode of the QCM sensor. A piezoelectric vibrator having an adsorption film and an excitation electrode for selectively adsorbing a target substance is brought into contact with a sample liquid, and the resonance frequency of the piezoelectric vibrator that changes when the target substance is adsorbed to the adsorption film is changed. A QCM sensor device for detecting and quantitatively analyzing the target substance,
A cover provided with a substrate for flowing the sample liquid, an injection hole for injecting the sample liquid, an absorption hole for absorbing the injected sample liquid, and a recess for flowing the sample liquid; A QCM sensor device comprising: a QCM sensor having an external connection electrode electrically connected to the excitation electrode; and an analyzer for quantitatively analyzing the target substance in response to a signal from the external connection electrode of the QCM sensor.   The QCM sensor device according to claim 4, wherein an absorption member is provided in a recess provided in the substrate or the cover.

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