calcium ion test strip

Abstract

The utility model provides a kind of calcium ion test piece, it is related to calcium ion detection technical field.The utility model provides calcium ion test piece low in cost, structure is ingenious, electrode, fluid cavity, check valve are integrated in single test piece, without external reference electrode or complex instrument, it can be applicable to the on-site detection of serum, water quality, food and other samples, and detection accuracy is high.

Description

Technical Field

[0001] This utility model relates to the field of calcium ion detection technology, and in particular to a calcium ion test strip. Background Technology

[0002] Calcium ions are important signaling molecules and structural components in living organisms, participating in physiological processes such as muscle contraction, nerve conduction, and bone formation. Rapid and accurate detection of calcium ions is of great significance in fields such as medical diagnostics (e.g., blood calcium testing), environmental monitoring (e.g., water hardness analysis), and the food industry (e.g., dairy product quality control).

[0003] Currently, the detection of calcium ions mainly faces the following problems:

[0004] (1) Atomic absorption spectroscopy: It has high precision but the equipment is expensive and requires professional personnel to operate.

[0005] (2) Fluorescent probe method: It has good sensitivity but poor probe stability and is easily affected by environmental interference.

[0006] (3) Traditional electrochemical method: 1. The electrode structure is complex and requires frequent maintenance (such as replenishing the reference electrode solution); 2. The selective membrane is prone to aging, which leads to signal drift (such as the electrode lifespan of only 7 days as described in CN103728356B); 3. The anti-interference ability is weak (such as the significant impact of Mg ions and pH changes).

[0007] In view of the above, this utility model is hereby proposed. Utility Model Content

[0008] The purpose of this invention is to provide a calcium ion test strip to solve at least one of the above-mentioned technical problems.

[0009] To achieve the above objectives, the following technical solution is adopted:

[0010] This utility model provides a calcium ion test piece, including an electrode substrate, a first patch, a second patch, a hydrophilic membrane, a working electrode, a reference electrode, a working electrode contact piece, and a reference electrode contact piece;

[0011] One end of the calcium ion sample is the injection end, and the other end is the signal transmission end; along the direction from the injection end to the signal transmission end, a working electrode and a reference electrode are sequentially arranged on the electrode substrate; the working electrode is a calcium ion selective electrode;

[0012] The working electrode contact piece is disposed at the signal transmission end of the electrode substrate and is electrically connected to the working electrode for the transmission of electrical signals.

[0013] The reference electrode contact piece is disposed at the signal transmission end of the electrode substrate and is electrically connected to the reference electrode for transmitting electrical signals.

[0014] The first patch is disposed on the electrode substrate, and openings are respectively provided at the working electrode and the reference electrode to expose the working electrode and the reference electrode, forming a first layer of working electrode point liquid cavity and a first layer of reference electrode point liquid cavity;

[0015] The second patch is placed on the first patch, and the central area of ​​the second patch is open to form a sample chamber and a waste liquid chamber; the sample chamber and the waste liquid chamber are separated by a one-way valve; the one-way valve is used to allow the sample in the sample chamber to flow into the waste liquid chamber; the first layer working electrode liquid chamber and the first layer reference electrode liquid chamber are located in the sample chamber area;

[0016] The hydrophilic membrane is disposed on the second patch. The sample inlet end of the hydrophilic membrane is provided with a sample inlet hole, which is connected to the sample chamber. The signal transmission end of the hydrophilic membrane is provided with an vent hole, which is connected to the waste liquid chamber.

[0017] As a further technical solution, the working electrode is composed of a silver paste layer, an electrolyte layer and a calcium ion selective membrane sequentially disposed on an electrode substrate.

[0018] As a further technical solution, the reference electrode is composed of a silver paste layer, an electrolyte layer and a PDMS film layer sequentially disposed on an electrode substrate.

[0019] As a further technical solution, the thickness of the first patch is 50-120um;

[0020] The diameter of the liquid cavity at the first working electrode point is 1-1.5 mm;

[0021] The diameter of the liquid cavity of the first reference electrode point is 1-1.5 mm.

[0022] As a further technical solution, it also includes a first identification electrode contact piece and a second identification electrode contact piece;

[0023] The first identification electrode contact and the second identification electrode contact are disposed on the signal transmission end of the electrode substrate and are electrically connected.

[0024] As a further technical solution, a third patch is also included;

[0025] The third patch is disposed between the first patch and the second patch, and has openings at the first working electrode point liquid cavity and the first reference electrode point liquid cavity, respectively, to expose the first working electrode point liquid cavity and the first reference electrode point liquid cavity, thus forming the second working electrode point liquid cavity and the second reference electrode point liquid cavity.

[0026] As a further technical solution, the thickness of the third patch is 50-120um;

[0027] The diameter of the liquid cavity at the second working electrode point is 1.5-1.9 mm;

[0028] The diameter of the liquid cavity of the second reference electrode point is 1.5-1.9 mm.

[0029] As a further technical solution, the thickness of the second patch is 500-1500um.

[0030] As a further technical solution, the one-way valve consists of two baffles, one end of which is fixed and the other end is freely movable.

[0031] As a further technical solution, there is at least one one-way valve.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] The calcium ion test strip provided by this utility model is low in cost and has a compact structure. It integrates electrodes, fluid chambers, and one-way valves into a single test strip, eliminating the need for external reference electrodes or complex instruments. It is suitable for on-site testing of samples such as serum, water, and food, and has high detection accuracy. Attached Figure Description

[0034] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0035] Figure 1 The calcium ion test piece provided in Example 1;

[0036] Figure 2 The calcium ion test piece provided in Example 2.

[0037] Icons: 1-Electrode substrate; 2-Working electrode contact; 3-Reference electrode contact; 4-First identification electrode contact; 5-Second identification electrode contact; 6-Working electrode; 7-Reference electrode; 8-First patch; 9-First working electrode liquid chamber; 10-First reference electrode liquid chamber; 11-Third patch; 12-Second working electrode liquid chamber; 13-Second reference electrode liquid chamber; 14-Second patch; 15-Sample chamber; 16-One-way valve; 17-Waste liquid chamber; 18-Hydrophilic membrane; 19-Inlet port; 20-Outlet port. Detailed Implementation

[0038] The embodiments and examples of this utility model will be described in detail below. However, those skilled in the art will understand that the following embodiments and examples are only for illustrating this utility model and should not be considered as limiting the scope of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model. Unless otherwise specified, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0039] This utility model provides a calcium ion test piece, including an electrode substrate 1, a first patch 8, a second patch 14, a hydrophilic membrane 18, a working electrode 6, a reference electrode 7, a working electrode contact piece 2, and a reference electrode contact piece 3.

[0040] One end of the calcium ion sample is the injection end, and the other end is the signal transmission end; along the direction from the injection end to the signal transmission end, a working electrode 6 and a reference electrode 7 are sequentially arranged on the electrode substrate 1; the working electrode 6 is a calcium ion selective electrode;

[0041] The working electrode contact piece 2 is disposed at the signal transmission end of the electrode substrate 1 and is electrically connected to the working electrode 6 for the transmission of electrical signals.

[0042] The reference electrode contact 3 is disposed at the signal transmission end of the electrode substrate 1 and is electrically connected to the reference electrode 7 for transmitting electrical signals.

[0043] The first patch 8 is disposed on the electrode substrate 1, and openings are respectively provided at the working electrode 6 and the reference electrode 7 to expose the working electrode 6 and the reference electrode 7, forming the first layer of working electrode point liquid cavity 9 and the first layer of reference electrode point liquid cavity 10.

[0044] The second patch 14 is placed on the first patch 8, and the central area of ​​the second patch 14 is open to form a sample chamber 15 and a waste liquid chamber 17; the sample chamber 15 and the waste liquid chamber 17 are separated by a one-way valve 16; the one-way valve 16 is used to allow the sample in the sample chamber 15 to flow into the waste liquid chamber 17; the first layer working electrode point liquid chamber 9 and the first layer reference electrode point liquid chamber 10 are located in the sample chamber 15 area;

[0045] The hydrophilic membrane 18 is disposed on the second patch 14. The sample inlet end of the hydrophilic membrane 18 is provided with a sample inlet hole 19, which is connected to the sample chamber 15. The signal transmission end of the hydrophilic membrane 18 is provided with an vent hole 20, which is connected to the waste liquid chamber 17.

[0046] This invention is based on the detection of calcium ions by the binding of calcium ions with a carrier (such as ETH 1001 ion carrier) in a selective membrane, which causes a change in membrane potential.

[0047] In this invention, the electrode substrate 1 is used to provide support for the electrode and the electrode contact sheet. This invention does not impose specific limitations on the material of the electrode substrate 1. In some optional embodiments, the electrode substrate 1 is a PET substrate.

[0048] In some optional embodiments, the working electrode 6 consists of a silver paste layer, an electrolyte layer and a calcium ion selective membrane sequentially disposed on the electrode substrate 1.

[0049] In some optional embodiments, the working electrode 6 is prepared as follows:

[0050] 1) First layer: Silver paste layer: Apply Ag-AgCl to the PET substrate to form a conductive substrate, cure at 100℃ for 10 minutes, with a paste thickness of 25um and a paste size of 800um.

[0051] 2) Second layer: Electrolyte layer: Dispensing of a gel electrolyte containing CaCl2 (0.1M), KCl (1M), and 1% sodium alginate, with a dispensing thickness of 25um and a dispensing size of 800um.

[0052] 3) Third layer: Calcium ion selective membrane: Dispense a THF solution containing ETH 1001 ion carrier (10mg), PVC (100mg), and plasticizer DOS (200mg), with a dispensing thickness of 25µm and a dispensing size of 800µm. Aging for 3 days at room temperature and humidity <20%.

[0053] In some optional embodiments, the reference electrode 7 consists of a silver paste layer, an electrolyte layer, and a PDMS film layer sequentially disposed on the electrode substrate 1.

[0054] In some optional embodiments, the preparation method of the reference electrode 7 includes the following steps:

[0055] 1) First layer: Silver paste layer: Apply Ag-AgCl to the PET substrate to form a conductive substrate, cure at 100℃ for 10 minutes, with a paste thickness of 25um and a paste size of 800um.

[0056] 2) Second layer: Electrolyte layer: Dispensing a gel electrolyte containing CaCl2 (0.1M), KCl (1M), and 1% sodium alginate, with a dispensing thickness of 25um and a dispensing size of 800um.

[0057] 3) PDMS film: made of 90% dimethoxysiloxane (PDMS) and 10% cyclohexane.

[0058] In some alternative embodiments, the thickness of the first patch 8 may be, for example, but not limited to, 50um, 100um or 120um, preferably 100um;

[0059] The diameter of the liquid cavity 9 of the first working electrode point can be, for example, but not limited to, 1 mm, 1.2 mm or 1.5 mm, preferably 1.2 mm;

[0060] The diameter of the first layer reference electrode point liquid cavity 10 can be, for example, but not limited to, 1 mm, 1.2 mm or 1.5 mm, preferably 1.2 mm.

[0061] The above settings ensure that the electrohydraulic volume of each test piece is consistent.

[0062] In some optional embodiments, a first identification electrode contact 4 and a second identification electrode contact 5 are also included;

[0063] The first identification electrode contact 4 and the second identification electrode contact 5 are disposed on the signal transmission end of the electrode substrate 1 and are electrically connected.

[0064] The first identification electrode contact 4 and the second identification electrode contact 5 are provided to identify whether the test strip is inserted or inserted correctly.

[0065] In some alternative implementations, a third patch 11 is also included;

[0066] The third patch 11 is disposed between the first patch 8 and the second patch 14, and openings are respectively provided at the first working electrode point liquid cavity 9 and the first reference electrode point liquid cavity 10 to expose the first working electrode point liquid cavity 9 and the first reference electrode point liquid cavity 10, forming the second working electrode point liquid cavity 12 and the second reference electrode point liquid cavity 13.

[0067] The dispensing volume can be increased by setting a third patch 11.

[0068] In some optional embodiments, the thickness of the third patch 11 may be, for example, but not limited to, 50um, 100um or 120um, preferably 100um;

[0069] The diameter of the liquid cavity 12 of the second working electrode point can be, for example, but not limited to, 1.5 mm, 1.7 mm or 1.9 mm, preferably 1.6 mm;

[0070] The diameter of the second reference electrode point liquid cavity 13 can be, for example, but not limited to, 1.5 mm, 1.7 mm or 1.9 mm, and is preferably 1.6 mm.

[0071] In some alternative embodiments, the thickness of the second patch 14 may be, for example, but not limited to, 500um, 1000um or 1500um, preferably 1000um.

[0072] In some alternative embodiments, the one-way valve 16 consists of two baffles, one end of which is fixed and the other end is freely movable.

[0073] When the sample flows from the sample chamber 15 to the waste liquid chamber 17, the one-way valve 16 opens; when the sample flows from the waste liquid chamber 17 to the sample chamber 15, the one-way valve 16 closes to prevent the waste liquid from flowing back into the sample chamber 15.

[0074] In some alternative implementations, there is at least one check valve 16.

[0075] The present invention will be further illustrated below with specific embodiments. However, it should be understood that these embodiments are only for more detailed illustration and should not be construed as limiting the present invention in any way.

[0076] In the following embodiments, the working electrode 6 consists of a silver paste layer, an electrolyte layer, and a calcium ion selective film sequentially disposed on the electrode substrate 1, and the preparation method is as follows:

[0077] 1) First layer: Silver paste layer: Apply Ag-AgCl to the PET substrate to form a conductive substrate, cure at 100℃ for 10 minutes, with a paste thickness of 25um and a paste size of 800um.

[0078] 2) Second layer: Electrolyte layer: Dispensing a gel electrolyte containing CaCl2 (0.1M), KCl (1M), and 1% sodium alginate, with a dispensing thickness of 25um and a dispensing size of 800um.

[0079] 3) Third layer: Calcium ion selective membrane: Dispense a THF solution containing ETH 1001 ion carrier (10mg), PVC (100mg), and plasticizer DOS (200mg), with a dispensing thickness of 25µm and a dispensing size of 800µm. Aging for 3 days at room temperature and humidity <20%.

[0080] The reference electrode 7 consists of a silver paste layer, an electrolyte layer, and a PDMS film layer sequentially disposed on the electrode substrate 1. The preparation method includes the following steps:

[0081] 1) First layer: Silver paste layer: Apply Ag-AgCl to the PET substrate to form a conductive substrate, cure at 100℃ for 10 minutes, with a paste thickness of 25um and a paste size of 800um.

[0082] 2) Second layer: Electrolyte layer: Dispensing a gel electrolyte containing CaCl2 (0.1M), KCl (1M), and 1% sodium alginate, with a dispensing thickness of 25um and a dispensing size of 800um.

[0083] 3) PDMS film: made of 90% dimethoxysiloxane (PDMS) and 10% cyclohexane.

[0084] The working electrode contact 2, the reference electrode contact 3, the first identification electrode contact 4, and the second identification electrode contact 5 are prepared by sputtering gold, with a gold thickness of 20 nm.

[0085] Example 1

[0086] A calcium ion test strip, such as Figure 1 As shown, it includes an electrode substrate 1, a first patch 8, a second patch 14, a hydrophilic membrane 18, a working electrode 6, a reference electrode 7, a working electrode contact 2, and a reference electrode contact 3;

[0087] One end of the calcium ion sample is the injection end, and the other end is the signal transmission end. Along the direction from the injection end to the signal transmission end, a working electrode 6 and a reference electrode 7 are sequentially arranged on the electrode substrate 1. The working electrode 6 is a calcium ion selective electrode.

[0088] The working electrode contact piece 2 is disposed at the signal transmission end of the electrode substrate 1 and is electrically connected to the working electrode 6 for the transmission of electrical signals.

[0089] The reference electrode contact 3 is disposed at the signal transmission end of the electrode substrate 1 and is electrically connected to the reference electrode 7 for the transmission of electrical signals.

[0090] The first patch 8 is disposed on the electrode substrate 1, and openings are respectively provided at the working electrode 6 and the reference electrode 7 to expose the working electrode 6 and the reference electrode 7, forming the first layer of working electrode point liquid cavity 9 and the first layer of reference electrode point liquid cavity 10.

[0091] The second patch 14 is placed on the first patch 8, and the central region of the second patch 14 is open to form a sample chamber 15 and a waste liquid chamber 17; the sample chamber 15 and the waste liquid chamber 17 are separated by a one-way valve 16; the one-way valve 16 is used to allow the sample in the sample chamber 15 to flow into the waste liquid chamber 17; the first layer working electrode point liquid chamber 9 and the first layer reference electrode point liquid chamber 10 are located in the sample chamber 15 region.

[0092] A hydrophilic membrane 18 is disposed on the second patch 14. The sample inlet end of the hydrophilic membrane 18 is provided with a sample inlet hole 19, which is connected to the sample chamber 15. The signal transmission end of the hydrophilic membrane 18 is provided with an vent hole 20, which is connected to the waste liquid chamber 17.

[0093] Among them, the electrode substrate 1 is a PET substrate with a thickness of 0.35mm; the first patch 8 is a polyester material with a thickness of 100um; the diameter of the first working electrode point liquid cavity 9 is 1200um; the diameter of the first reference electrode point liquid cavity 10 is 1200um; the second patch 14 is a foam double-sided adhesive with a thickness of 800um; and the one-way valve 16 consists of two baffles with one end fixed and the other end freely movable.

[0094] Example 2

[0095] A calcium ion test strip, such as Figure 2 As shown, it includes an electrode substrate 1, a first patch 8, a third patch 11, a second patch 14, a hydrophilic membrane 18, a working electrode 6, a reference electrode 7, a working electrode contact 2, a reference electrode contact 3, a first identification electrode contact 4, and a second identification electrode contact 5.

[0096] One end of the calcium ion sample is the injection end, and the other end is the signal transmission end. Along the direction from the injection end to the signal transmission end, a working electrode 6 and a reference electrode 7 are sequentially arranged on the electrode substrate 1. The working electrode 6 is a calcium ion selective electrode.

[0097] The working electrode contact piece 2 is disposed at the signal transmission end of the electrode substrate 1 and is electrically connected to the working electrode 6 for the transmission of electrical signals.

[0098] The reference electrode contact 3 is disposed at the signal transmission end of the electrode substrate 1 and is electrically connected to the reference electrode 7 for the transmission of electrical signals.

[0099] The first identification electrode contact 4 and the second identification electrode contact 5 are disposed on the signal transmission end of the electrode substrate 1 and are electrically connected;

[0100] The first patch 8 is disposed on the electrode substrate 1, and openings are respectively provided at the working electrode 6 and the reference electrode 7 to expose the working electrode 6 and the reference electrode 7, forming the first layer of working electrode point liquid cavity 9 and the first layer of reference electrode point liquid cavity 10.

[0101] The third patch 11 is disposed between the first patch 8 and the second patch 14, and openings are respectively provided at the first working electrode point liquid cavity 9 and the first reference electrode point liquid cavity 10 to expose the first working electrode point liquid cavity 9 and the first reference electrode point liquid cavity 10, forming the second working electrode point liquid cavity 12 and the second reference electrode point liquid cavity 13.

[0102] The second patch 14 is placed on the third patch 11, and the central area of ​​the second patch 14 is open to form a sample chamber 15 and a waste liquid chamber 17; the sample chamber 15 and the waste liquid chamber 17 are separated by a one-way valve 16; the one-way valve 16 is used to allow the sample in the sample chamber 15 to flow into the waste liquid chamber 17; the first layer working electrode point liquid chamber 9 and the first layer reference electrode point liquid chamber 10 are located in the sample chamber 15 area.

[0103] A hydrophilic membrane 18 is disposed on the second patch 14. The sample inlet end of the hydrophilic membrane 18 is provided with a sample inlet hole 19, which is connected to the sample chamber 15. The signal transmission end of the hydrophilic membrane 18 is provided with an vent hole 20, which is connected to the waste liquid chamber 17.

[0104] The electrode substrate 1 is a PET substrate with a thickness of 0.35 mm; the first patch 8 is made of polyester material with a thickness of 100 μm; the diameter of the first working electrode point liquid cavity 9 is 1200 μm; the diameter of the first reference electrode point liquid cavity 10 is 1200 μm; the third patch 11 is made of polyester material with a thickness of 100 μm; the diameter of the second working electrode point liquid cavity 12 is 1600 μm; the diameter of the second reference electrode point liquid cavity 13 is 1600 μm; the second patch 14 is double-sided foam adhesive with a thickness of 800 μm; and the one-way valve 16 consists of two baffles, one fixed at one end and freely movable at the other end, with a total of two one-way valves 16.

[0105] Experimental Example 1

[0106] Taking the calcium ion test strip provided in Example 2 as an example, calcium ions are detected. The detection process is as follows:

[0107] Calibration solution addition: 50 μL of calibration solution is added through the injection port, ensuring it covers both the working electrode 6 and the reference electrode 7. The solution flows from the sample chamber 15 to the one-way valve 16, at which point the addition is stopped, and the calibration solution remains stationary. The analyzer collects the relative potential value E between the working electrode 6 and the reference electrode 7. Then, the above steps are repeated to detect the relative potential values ​​of calibration solutions with different calcium ion concentrations (C). The data is fitted using the function E = klnC + b to determine k and b.

[0108] Sample addition: 50 μL of sample (blood sample with unknown calcium ion concentration) is added through the inlet. The sample covers the working electrode 6 and the reference electrode 7 respectively. It flows from the sample chamber 15 to the one-way valve 16, and the original calibration solution is pushed from the sample chamber 15 into the waste liquid chamber 17. The sample addition is stopped, and the sample is in a static state. The analyzer collects the relative potential value E1 between the working electrode 6 and the reference electrode 7. Based on the known k, b, and the collected sample potential value E1, the calcium ion concentration C1 of the sample is calculated.

[0109] The test results of this novel calcium ion test strip, obtained by testing a series of samples (blood samples with unknown calcium ion concentrations), are as follows:

[0110] Linear range <![CDATA[0.1-10mM Ca 2+ ]]> Covering physiological concentration range Accuracy (Recovery Rate) 96.5％-103.3％ Deviation ≤ 5% Precision (CV) 2.1% within batch ≤3％

[0111] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. A calcium ion test strip, characterized in that, It includes an electrode substrate (1), a first patch (8), a second patch (14), a hydrophilic membrane (18), a working electrode (6), a reference electrode (7), a working electrode contact (2), and a reference electrode contact (3); One end of the calcium ion sample is the injection end, and the other end is the signal transmission end; along the direction from the injection end to the signal transmission end, a working electrode (6) and a reference electrode (7) are sequentially arranged on the electrode substrate (1); the working electrode (6) is a calcium ion selective electrode; The working electrode contact piece (2) is disposed at the signal transmission end of the electrode substrate (1) and is electrically connected to the working electrode (6) for the transmission of electrical signals; The reference electrode contact piece (3) is disposed at the signal transmission end of the electrode substrate (1) and is electrically connected to the reference electrode (7) for transmitting electrical signals; The first patch (8) is disposed on the electrode substrate (1) and has openings at the working electrode (6) and the reference electrode (7) respectively, exposing the working electrode (6) and the reference electrode (7) to form the first working electrode point liquid cavity (9) and the first reference electrode point liquid cavity (10). The second patch (14) is placed on the first patch (8), and the central area of ​​the second patch (14) is open to form a sample chamber (15) and a waste liquid chamber (17); the sample chamber (15) and the waste liquid chamber (17) are separated by a one-way valve (16); the one-way valve (16) is used to allow the sample in the sample chamber (15) to flow into the waste liquid chamber (17); the first layer working electrode liquid chamber (9) and the first layer reference electrode liquid chamber (10) are located in the sample chamber (15) area; The hydrophilic membrane (18) is disposed on the second patch (14). The sample inlet end of the hydrophilic membrane (18) is provided with a sample inlet hole (19), which is connected to the sample chamber (15). The signal transmission end of the hydrophilic membrane (18) is provided with an vent hole (20), which is connected to the waste liquid chamber (17).

2. The calcium ion test strip according to claim 1, characterized in that, The working electrode (6) consists of a silver paste layer, an electrolyte layer and a calcium ion selective membrane sequentially disposed on the electrode substrate (1).

3. The calcium ion test strip according to claim 1, characterized in that, The reference electrode (7) consists of a silver paste layer, an electrolyte layer and a PDMS film layer sequentially disposed on the electrode substrate (1).

4. The calcium ion test strip according to claim 1, characterized in that, The thickness of the first patch (8) is 50-120 μm; The diameter of the liquid cavity (9) of the first working electrode point is 1-1.5 mm; The diameter of the first layer reference electrode point liquid cavity (10) is 1-1.5 mm.

5. The calcium ion test strip according to claim 1, characterized in that, It also includes a first identification electrode contact (4) and a second identification electrode contact (5); The first identification electrode contact (4) and the second identification electrode contact (5) are disposed on the signal transmission end of the electrode substrate (1) and are electrically connected.

6. The calcium ion test strip according to claim 1, characterized in that, It also includes the third patch (11); The third patch (11) is disposed between the first patch (8) and the second patch (14), and openings are respectively provided at the first working electrode point liquid cavity (9) and the first reference electrode point liquid cavity (10) to expose the first working electrode point liquid cavity (9) and the first reference electrode point liquid cavity (10), forming the second working electrode point liquid cavity (12) and the second reference electrode point liquid cavity (13).

7. The calcium ion test strip according to claim 6, characterized in that, The thickness of the third patch (11) is 50-120 μm; The diameter of the liquid cavity (12) of the second working electrode is 1.5-1.9 mm; The diameter of the second layer reference electrode point liquid cavity (13) is 1.5-1.9 mm.

8. The calcium ion test strip according to claim 1, characterized in that, The thickness of the second patch (14) is 500-1500um.

9. The calcium ion test strip according to claim 1, characterized in that, The one-way valve (16) consists of two baffles, one end of which is fixed and the other end is free to move.

10. The calcium ion test strip according to claim 1, characterized in that, There is at least one one-way valve (16).

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