A sensor with detection function

Abstract

The present invention belongs to the field of MEMS biosensor detection technology, and specifically relates to a sensor with detection function, including a substrate, a detection unit and a reference unit, the detection unit and the reference unit are arranged on the substrate, the mass load change of the detection unit occurs in the vertical direction of the detection unit plane, the mass load change of the detection unit causes the capacitance change inside the detection unit, and the concentration of the detected object is calculated according to the capacitance change. A molecular layer membrane is assembled on the surface of the sensor sensitive unit to specifically bind to the detected substance, and the signal change before and after the specific binding of the two is converted into an electrical signal output, so as to realize the real-time, label-free, and high-sensitivity detection function of the detected substance; at the same time, the reference detection unit is designed to remove the influence of the noise signal, and the design of the reference unit improves the accuracy of the detection.

Description

Technical Field

[0001] The present invention relates to the technical field of MEMS biosensor detection, and in particular to an array sensor with detection function. Background Art

[0002] At present, the conventional PCR, ELISA, kits, etc. are mainly used to detect biological molecules and other substances. For example, a rapid detection kit disclosed in patent application CN 114778838 A, based on pathogen detection of near-infrared fluorescent nanoparticles, needs to observe the morphology and binding of bacteria captured by near-infrared fluorescent nanospheres and superparamagnetic nanospheres through transmission electron microscopy or fluorescence microscopy to obtain the detection results. The above detection process has many interference factors and is costly.

[0003] Existing sensor detection methods still require fluorescent labeling, which takes a long time to detect, is complex to operate, and has low sensitivity.

[0004] Therefore, there is a need for a solution to solve the problems in the prior art. Summary of the invention

[0005] To solve the above technical problems, according to one aspect of the present invention, the present invention provides a technical solution, aiming to provide a new array sensor based on MEMS process, which uses the shear mode of the material in a liquid or gas environment to achieve specific detection of the substance to be detected.

[0006] A sensor with a detection function comprises a substrate, a detection unit and a reference unit, wherein the detection unit and the reference unit are arranged on the substrate, and a mass load change of the detection unit occurs in a direction perpendicular to the plane of the detection unit. The mass load change of the detection unit causes a capacitance change inside the detection unit, and the concentration of the object to be detected is calculated based on the capacitance change.

[0007] As a preferred solution of a sensor with detection function described in the present invention, the detection unit includes an upper electrode, a piezoelectric crystal, and a lower electrode arranged in sequence from top to bottom, the piezoelectric crystal is arranged between the upper electrode and the lower electrode, and the upper electrode and the lower electrode are respectively connected to the substrate through a supporting structure, so that the detection unit is in a suspended state.

[0008] As a preferred solution of the sensor with detection function described in the present invention, the upper electrode and the lower electrode are parallel to each other and spaced apart.

[0009] As a preferred solution of a sensor with detection function described in the present invention, the reference unit includes an upper electrode, a piezoelectric crystal, and a lower electrode arranged in sequence from top to bottom, the piezoelectric crystal is arranged between the upper electrode and the lower electrode, and the upper electrode and the lower electrode are respectively connected to the substrate through supporting components, so that the reference unit is in a suspended state.

[0010] As a preferred solution of the sensor with detection function described in the present invention, wherein: the upper electrode surface of the detection unit is provided with an aptamer molecular layer membrane; the upper electrode surface of the reference unit is provided with an anti-fouling molecular layer membrane.

[0011] As a preferred solution of a sensor with detection function described in the present invention, wherein: the support assembly includes a first support structure and a second support structure, the first support structure and the second support structure are relatively arranged on the surface of the substrate, the first support structure is connected to the upper electrode, and the second support structure is connected to the lower electrode.

[0012] As a preferred solution of a sensor with detection function described in the present invention, wherein: the first supporting structure includes a first vertical segment and a first horizontal segment, the first vertical segment and the first horizontal segment are perpendicular to each other, and the bottom surface of the first horizontal segment abuts the top surface of the upper electrode, and the first vertical segment is arranged on the surface of the substrate.

[0013] As a preferred solution of a sensor with detection function described in the present invention, wherein: the second supporting structure includes a second vertical segment and a second horizontal segment, the second vertical segment and the second horizontal segment are perpendicular to each other, and the top surface of the second horizontal segment abuts against the bottom surface of the lower electrode, and the second vertical segment is arranged on the surface of the substrate.

[0014] As a preferred solution of the sensor with detection function described in the present invention, the projection areas of the upper electrode and the lower electrode on the piezoelectric crystal at least partially overlap.

[0015] As a preferred solution of the sensor with detection function described in the present invention, a sensitive film is arranged on the surface of the upper electrode.

[0016] As a preferred solution of the sensor with detection function described in the present invention, the detection unit and the reference unit are arranged adjacent to each other on the substrate to form a sensor unit, and the sensor unit is distributed in an array along the axis of the substrate on the substrate.

[0017] Compared with the prior art, the beneficial effects of the technical solution of the present invention are as follows:

[0018] (1) In the sensor with detection function of the present invention, when the mass load changes, the relative area between the upper electrode and the lower electrode changes, so that the capacitance value between the two changes, which is converted into an electrical signal output, thereby realizing real-time, label-free detection of the substance to be detected.

[0019] (2) The sensor with detection function of the present invention realizes specific detection of the substance to be detected by utilizing the shear mode of the material to achieve minimum attenuation of signal energy, thereby realizing high-sensitivity detection of the substance to be detected and improving the detection sensitivity.

[0020] (3) In the sensor with detection function of the present invention, the signal detected by the designed reference unit can be used as a noise signal to subtract from the detection unit signal, thereby obtaining an accurate detection signal. The design of the reference unit improves the accuracy of detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0022] Figure 1 This is a schematic diagram of the structure of a sensor with a detection function according to the present invention;

[0023] Figure 2 This is a schematic diagram of the structure of a sensor detection unit with detection function according to the present invention;

[0024] Figure 3 This is a detection principle diagram of a sensor detection unit with detection function of the present invention.

[0025] Description of Figure Numbers:

[0026] 1-detection unit, 2-reference unit, 3-piezoelectric crystal, 4-substrate;

[0027] 11-upper electrode, 12-aptamer molecular layer membrane, 13-specific binding substance, 14-support component, 15-lower electrode.

[0028] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0029] The following will be described clearly and completely in conjunction with the technical solutions in the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0031] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0032] The present invention aims to provide a novel array sensor which is based on MEMS technology and uses the shear mode of materials in a liquid or gas environment to achieve specific detection of substances to be detected.

[0033] In order to achieve the above functions, a detection sensor technology solution is proposed, including a substrate 4, a detection unit 1 and a reference unit 2, wherein the detection unit 1 and the reference unit 2 are arranged on the substrate 4, and the detection unit 1 is configured to detect the substance to be detected by utilizing the shear mode of the material.

[0034] Example 1

[0035] A sensor with a detection function comprises a substrate 4, a detection unit 1 and a reference unit 2, wherein the detection unit 1 and the reference unit 2 are arranged on the substrate 4, the mass load change of the detection unit 1 occurs in a direction perpendicular to the plane of the detection unit 1, the mass load change of the detection unit 1 causes the capacitance change inside the detection unit 1, and the concentration of the object to be detected is calculated based on the capacitance change.

[0036] The detection unit 1 includes an upper electrode 11, a piezoelectric crystal 3, and a lower electrode 15 arranged in sequence from top to bottom. The piezoelectric crystal 3 is arranged between the upper electrode 11 and the lower electrode 15. The upper electrode 11 and the lower electrode 15 are respectively connected to the substrate 4 through a supporting component 14, so that the detection unit 1 is in a suspended state.

[0037] The reference unit 2 includes an upper electrode 11, a piezoelectric crystal 3, and a lower electrode 15 arranged in sequence from top to bottom. The piezoelectric crystal 3 is arranged between the upper electrode 11 and the lower electrode 15. The upper electrode 11 and the lower electrode 15 are respectively connected to the substrate 4 through a supporting component 14, so that the reference unit 2 is in a suspended state.

[0038] The surface of the upper electrode 11 of the detection unit 1 is provided with an aptamer molecular layer membrane; the surface of the upper electrode 11 of the reference unit 2 is provided with an antifouling molecular layer membrane.

[0039] like Figure 1 As shown in the structural diagram, the detection unit 1 and the reference unit 2 are arranged adjacent to each other. The surface assembly of the detection unit 1 can specifically bind to the substance to be detected to form a specific binding substance 13; the surface of the reference unit 2 has an anti-fouling molecular layer, which can effectively block non-specific binding and avoid interference of impurities on the surface. The upper electrode 11 and the lower electrode 15 are made of conductive materials. By applying an alternating electric field, the shear vibration of the piezoelectric crystal 3 with a special cut shape can be induced, so that the entire unit array can realize real-time detection under liquid phase conditions, ensuring that the sound wave energy is not attenuated into the liquid.

[0040] like Figure 2-3 As shown, a support assembly 14 is used on the surface of the detection unit 1 to make the detection unit 1 suspended. When the substance to be detected combines with the aptamer molecular layer membrane, the surface mass load of the detection unit 1 changes. Under the shear state, the relative area between the upper electrode 11 and the lower electrode 15 changes, so that the capacitance changes, as shown in FIG. Figure 3 As shown, the detection is finally achieved.

[0041] The reference unit 2 has the same structure as the detection unit 1, except that the reference unit 2 has an anti-fouling molecular layer membrane on its surface, which can effectively prevent the non-specific binding of the substance to be detected with the unit structure. The signal detected by the reference unit 2 can be used as a noise signal to subtract from the signal of the detection unit 1, thereby obtaining an accurate detection signal.

[0042] By utilizing the shear mode of the material to achieve specific detection of the substance to be detected, horizontal shearing is achieved to achieve minimum attenuation of signal energy, and high-sensitivity detection of the substance to be detected is achieved, thereby improving the detection sensitivity. After the mass load changes, the relative area of ​​the upper electrode 11 and the lower electrode 15 changes, so that the capacitance value between the two changes, which is converted into an electrical signal output, thereby achieving real-time, label-free detection of the substance to be detected. The design of the reference unit 2 improves the accuracy of the detection.

[0043] Example 2

[0044] A sensor with a detection function comprises a substrate 4, a detection unit 1 and a reference unit 2, wherein the detection unit 1 and the reference unit 2 are arranged on the substrate 4, the mass load change of the detection unit 1 occurs in a direction perpendicular to the plane of the detection unit 1, the mass load change of the detection unit 1 causes the capacitance change inside the detection unit 1, and the concentration of the object to be detected is calculated based on the capacitance change.

[0045] The detection unit 1 and the reference unit 2 are arranged adjacent to each other on the substrate 4 to form a sensor unit. The sensor units are distributed in an array on the substrate 4 along the axis of the substrate 4 .

[0046] like Figure 1 As shown, each detection unit 1 of the entire array has an alternating voltage applied to the surface of the upper and lower electrodes 15. Under the action of the alternating electric field, when the frequency of the alternating electric field is equal to the fundamental frequency of the crystal, the crystal will resonate.

[0047] like Figure 2 As shown, the surface of the upper electrode 11 is made into a sensitive membrane, and its surface can be modified with an aptamer molecular membrane 12 that specifically binds to the substance to be detected. After binding, the surface mass load of the detection unit 1 will change; the lower electrode 15 is an excitation electrode and is kept highly clean.

[0048] It should be pointed out that the material of the sensitive film on the surface of the upper electrode 11 can be gold, graphene, molybdenum disulfide, etc., to increase the sensitivity of detection.

[0049] In summary, compared with the prior art, this proposal provides a new type of sensor and array based on MEMS processing, which uses the shear mode of the material in a liquid or gas environment to achieve specific detection of the substance to be detected. The piezoelectric crystal 3 is processed with a special cut piezoelectric material to achieve shear mode vibration, thereby ensuring that the acoustic wave energy excited under liquid conditions is not attenuated. After the mass load on the surface of the upper electrode 11 changes, the vibration frequency of the piezoelectric crystal 3 changes, which is converted into an electrical signal output to achieve real-time, label-free, and high-sensitivity detection of the substance to be detected. At the same time, the entire array includes a detection unit 1 and a reference unit 2. The signal of the detection unit 1 is subtracted from the noise signal of the reference unit 2, so that the signal of the target substance to be detected can be accurately read.

[0050] In addition, the detection unit 1 can be an optical and / or piezoresistive detection unit 1 and / or a surface stress detection unit 1 to realize the detection function, and the present application does not limit its structure. Those skilled in the art will appreciate that any known detection technology can be used. The basic technology in MEMS manufacturing includes depositing a thin film of material on a substrate, applying a pattern to the film by photolithography, and any type of known material can also be used to construct a MEMS device.

[0051] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A sensor with detection function, characterized in that: The device comprises a substrate, a detection unit and a reference unit, wherein the detection unit and the reference unit are arranged on the substrate, the mass load change of the detection unit occurs in a direction perpendicular to the plane of the detection unit, the mass load change of the detection unit causes the capacitance change inside the detection unit, and the concentration of the object to be detected is calculated according to the capacitance change; The detection unit includes an upper electrode, a piezoelectric crystal, and a lower electrode arranged in sequence from top to bottom. The piezoelectric crystal is arranged between the upper electrode and the lower electrode. The upper electrode and the lower electrode are respectively connected to the substrate through a supporting structure so that the detection unit is in a suspended state. The upper electrode and the lower electrode are parallel to each other and arranged at intervals.

2. A sensor with detection function according to claim 1, characterized in that: The reference unit includes an upper electrode, a piezoelectric crystal, and a lower electrode arranged in sequence from top to bottom. The piezoelectric crystal is arranged between the upper electrode and the lower electrode. The upper electrode and the lower electrode are respectively connected to the substrate through a supporting structure, so that the reference unit is in a suspended state.

3. A sensor with detection function according to claim 2, characterized in that: The upper electrode surface of the detection unit is provided with an aptamer molecular layer membrane; the upper electrode surface of the reference unit is provided with an antifouling molecular layer membrane.

4. A sensor with detection function according to claim 3, characterized in that: The support structure includes a first support structure and a second support structure. The first support structure and the second support structure are arranged opposite to each other on the surface of the substrate. The first support structure is connected to the upper electrode, and the second support structure is connected to the lower electrode.

5. A sensor with detection function according to claim 4, characterized in that: The first supporting structure includes a first vertical segment and a first horizontal segment, the first vertical segment and the first horizontal segment are perpendicular to each other, and the bottom surface of the first horizontal segment abuts against the top surface of the upper electrode, and the first vertical segment is arranged on the surface of the substrate.

6. A sensor with detection function according to claim 4, characterized in that: The second supporting structure includes a second vertical segment and a second horizontal segment, the second vertical segment and the second horizontal segment are perpendicular to each other, and the top surface of the second horizontal segment abuts against the bottom surface of the lower electrode, and the second vertical segment is arranged on the surface of the substrate.

7. A sensor with detection function according to claim 4, characterized in that: The projection areas of the upper electrode and the lower electrode on the piezoelectric crystal at least partially overlap.

8. A sensor with detection function according to claim 3, characterized in that: A sensitive film is arranged on the surface of the upper electrode.

9. A sensor with detection function according to claim 1, characterized in that: The detection unit and the reference unit are arranged adjacent to each other on the substrate to form a sensor unit, and the sensor units are distributed in an array along the axis of the substrate on the substrate.

Images