Human body exhaled gas detection system and preparation method and detection method thereof

Abstract

The invention discloses a human body exhaled gas detection system, a preparation method thereof and a human body exhaled gas detection method, the detection system comprises an antenna and a capacitance-inductance wireless passive sensor, the capacitance-inductance wireless passive sensor comprises a flexible substrate, an inductance coil, a niobium selenide nanosheet sensitive film and an interdigital electrode, the inductance coil is connected to the flexible substrate, the niobium selenide nanosheet sensitive film covers the interdigital electrode to form an ammonia gas sensitive electrode, the ammonia gas sensitive electrode is connected with the inductance coil to form a capacitance-inductance wireless passive sensor, and the antenna can be in wireless signal connection with the capacitance-inductance wireless passive sensor through an electromagnetic coupling effect. The return loss of the capacitance-inductance wireless passive sensor is detected, so that the concentration of ammonia gas in exhaled gas is detected. The human body exhaled gas detection system is small in size, compact in structure, low in cost, free of operation of professionals and high in portability.

Description

Technical Field

[0001] The present application relates to the technical field of wireless passive gas sensors, and in particular to a human exhaled gas detection system and a preparation method thereof, as well as a human exhaled gas detection method. Background Art

[0002] Many kidney diseases such as uremia can lead to impaired kidney function, endanger human health, and reduce the quality of life. When kidney function is impaired, nitrogen metabolites cannot be effectively eliminated from the body, causing them to accumulate in the body. In medical testing, the concentration of nitrogen metabolites in body fluids can be used to assess the condition of impaired kidney function. However, the method of detecting impaired kidney function through body fluids is invasive. In addition to causing great pain to patients, this method of testing also relies on professional technicians and testing equipment, resulting in high testing costs.

[0003] Studies have shown that individuals with impaired kidney function have abnormal ammonia levels in their exhaled breath. This is because ammonia is one of the products of nitrogen metabolism in the human body. Under normal circumstances, it can be excreted through the kidneys when kidney function is normal. When kidney function is impaired, ammonia cannot be effectively excreted and accumulates in the body, causing its concentration in the human exhaled breath to increase significantly. Therefore, by detecting the ammonia concentration in the human exhaled breath, the degree of damage to kidney function can be indirectly reflected, thereby guiding the corresponding treatment and management measures. The technology of detecting ammonia concentration provides a low-cost and non-invasive means of assessing kidney function; ammonia concentration is generally detected using ammonia sensors, and the current ammonia sensors are wired types. Wired ammonia sensors need to be connected to professional instruments to test the sensor signal, which limits the portability of the detection system. Summary of the invention

[0004] Based on this, it is necessary to provide a human exhaled gas detection system. The human exhaled gas detection system of the present invention has small size, compact structure, low cost, does not require professional operation and is highly portable.

[0005] An embodiment of the present application provides a human exhaled gas detection system.

[0006] A human exhaled gas detection system comprises an antenna and a capacitor-inductor wireless passive sensor, wherein the capacitor-inductor wireless passive sensor comprises a flexible substrate, an inductor coil, a niobium selenide nanosheet sensitive film and interdigital electrodes, wherein the inductor coil is connected to the flexible substrate, the niobium selenide nanosheet sensitive film covers the interdigital electrodes to form an ammonia sensitive electrode, the ammonia sensitive electrode is connected to the inductor coil to form the capacitor-inductor wireless passive sensor, and the antenna can be connected to the capacitor-inductor wireless passive sensor through an electromagnetic coupling effect to perform a wireless signal connection, so as to detect the return loss of the capacitor-inductor wireless passive sensor and thus detect the ammonia concentration in the exhaled gas.

[0007] In some embodiments, the inductor coil is in a U-shaped multi-turn structure from inside to outside.

[0008] In some embodiments, the antenna has a ring structure.

[0009] An embodiment of the present application also provides a method for preparing a human exhaled gas detection system.

[0010] A method for preparing a human exhaled gas detection system comprises the following steps:

[0011] Dispersing bulk niobium selenide in a first dispersing solvent, and performing water bath ultrasonication to obtain a mixed solution; performing ultrasonic crushing on the mixed solution to peel off bulk niobium selenide to obtain a niobium selenide solution; centrifuging the niobium selenide solution to collect a supernatant; centrifuging the supernatant to collect precipitated niobium selenide powder, and washing the niobium selenide powder at least three times with a cleaning solution, collecting a sample after washing, and freeze-drying the sample to obtain niobium selenide nanosheets; adding the niobium selenide nanosheets to a second dispersing solvent, and performing ultrasonic treatment to form a uniformly distributed niobium selenide nanosheet solution for standby use;

[0012] Covering a first mask having a patterned coil channel on a flexible substrate, and preparing an inductor coil on the flexible substrate through the patterned coil channel of the first mask;

[0013] Filling conductive silver paste into the connection holes at the two ends of the inductor coil on the flexible substrate, and drying to form conductive connecting parts;

[0014] Covering the flexible substrate with a second mask having patterned electrode channels, and preparing interdigitated electrodes on the flexible substrate through the patterned electrode channels of the second mask; and

[0015] The niobium selenide nanosheet solution is evenly disposed on the interdigital electrodes and dried to form a niobium selenide nanosheet sensitive film. The niobium selenide nanosheet sensitive film and the interdigital electrodes constitute an ammonia sensitive electrode. The two electrodes of the interdigital electrodes are respectively connected to the two ends of the inductor coil through the conductive connector.

[0016] In some of the embodiments, the mass volume ratio of the bulk niobium selenide to the first dispersing solvent is (100 mg-200 mg): (100 mL-200 mL).

[0017] In some embodiments, the first dispersing solvent includes 55% ethanol.

[0018] In some embodiments, the water bath sonication time is 25 min to 40 min.

[0019] In some of the embodiments, during the ultrasonic crushing treatment, the mixed solution is placed in an ultrasonic crusher, and the bulk niobium selenide is peeled off at an ultrasonic power of 200 W to 300 W for 3 h to 4 h to obtain the niobium selenide solution.

[0020] In some embodiments, when the niobium selenide solution is centrifuged, the niobium selenide solution is centrifuged in a centrifuge at 1500 rpm to 2000 rpm for 15 min to 20 min.

[0021] In some embodiments, when the supernatant is centrifuged, the supernatant is placed in a centrifuge and centrifuged at 8000 rpm to 10000 rpm for 15 min to 20 min.

[0022] In some embodiments, the cleaning solution comprises 95% ethanol.

[0023] In some embodiments, during freeze drying, the sample collected and washed in the step is freeze dried for at least 12 h.

[0024] In some embodiments, the mass volume ratio of the niobium selenide nanosheets to the second dispersing solvent is (10 mg~20 mg): (5 mL~10 mL).

[0025] In some embodiments, the second dispersing solvent comprises analytical grade ethanol.

[0026] In some of the embodiments, when the ultrasonic treatment is performed to form a uniformly distributed niobium selenide nanosheet solution, the ultrasonic treatment time is 15 min to 30 min.

[0027] In some embodiments, the inductor coil is prepared by the following steps:

[0028] A first copper metal layer is magnetron sputtered on the flexible substrate through the patterned coil channel of the first mask, a second copper metal layer with a thickness of 8 μm to 10 μm is electroplated on the first copper metal layer, a first nickel metal layer with a thickness of 2 μm to 3 μm is electroplated on the second copper metal layer, and a first gold metal layer with a thickness of 0.05 μm to 0.1 μm is electroplated on the first nickel metal layer.

[0029] In some embodiments, the conductive paste includes silver paste.

[0030] In some embodiments, when drying to form the conductive connecting member, the drying is performed at a temperature of 60° C. to 70° C. for at least 30 minutes.

[0031] In some embodiments, when preparing interdigitated electrodes on the flexible substrate through the patterned electrode channels of the second mask, the steps include:

[0032] A third copper metal layer is magnetron sputtered on the flexible substrate through the patterned electrode channel of the second mask, a fourth copper metal layer with a thickness of 8 μm to 10 μm is electroplated on the third copper metal layer, a second nickel metal layer with a thickness of 2 μm to 3 μm is electroplated on the fourth copper metal layer, and a second gold metal layer with a thickness of 0.05 μm to 0.1 μm is electroplated on the second nickel metal layer to obtain an interdigitated electrode.

[0033] In some embodiments, the niobium selenide nanosheet solution is uniformly disposed on the interdigital electrodes and dried to form a niobium selenide nanosheet sensitive film, which includes the following steps: using inkjet printing technology to uniformly print the niobium selenide nanosheet solution on the interdigital electrodes.

[0034] In some embodiments, when drying to form the niobium selenide nanosheet sensitive film, the drying temperature is 20° C. to 30° C.

[0035] An embodiment of the present application also provides a method for detecting human exhaled gas.

[0036] A method for detecting human exhaled gas, using the above-mentioned human exhaled gas detection system, or the human exhaled gas detection system prepared by the above-mentioned preparation method, comprises the following steps:

[0037] The human exhaled gas detection system is placed in the gas to be tested, and the ammonia molecules in the gas to be tested provide electrons to the niobium selenide nanosheet material on the niobium selenide nanosheet sensitive film of the human exhaled gas detection system, causing the conductivity of the niobium selenide nanosheet sensitive film to change, and causing the impedance of the capacitor-inductor wireless passive sensor based on the niobium selenide nanosheet sensitive film to change, so that the return loss S11 of the capacitor-inductor wireless passive sensor changes, and the control antenna and the capacitor-inductor wireless passive sensor are connected by electromagnetic coupling effect to realize wireless signal connection, and the return loss S11 of the capacitor-inductor wireless passive sensor is detected, and the ammonia concentration in the gas to be tested is detected based on the return loss S11. The above-mentioned human exhaled gas detection system is small in size, compact in structure, low in cost, does not require professional operation and is highly portable. The present application can be used to detect the ammonia concentration in human exhaled gas to indirectly reflect the degree of damage to kidney function, thereby guiding corresponding treatment and management measures.

[0038] In summary, compared with the prior art, the human exhaled gas detection system of the present invention has the following beneficial effects:

[0039] (1) The wireless signal transmission characteristics based on the electromagnetic coupling effect of the present application can realize real-time monitoring of the ammonia concentration in the exhaled gas to be tested, with high detection efficiency and accurate detection results.

[0040] (2) The present application has a simple and compact structure, a very small overall size, good mobility, and is easy to carry. It can be used for personalized medical, testing and other services.

[0041] (3) The circuit of the present application is relatively simple and does not require external power supply. The manufacturing and use costs are relatively low. It can be deployed on a large scale and widely used, which can significantly reduce the detection cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can obtain other drawings based on these drawings without creative work.

[0043] In order to more completely understand the present application and its beneficial effects, the following description will be given in conjunction with the accompanying drawings. In the following description, the same reference numerals represent the same parts.

[0044] Figure 1 It is a structural schematic diagram of a human exhaled gas detection system according to an embodiment of the present invention;

[0045] Figure 2This is a structural diagram of a capacitor-inductor wireless passive sensor based on niobium selenide nanosheets according to an embodiment of the present invention;

[0046] Figure 3 This is a test principle diagram of a capacitor-inductor wireless passive sensor based on niobium selenide nanosheets according to an embodiment of the present invention;

[0047] Figure 4 This is a schematic diagram of a preparation process of a capacitor-inductor wireless passive sensor based on niobium selenide nanosheets according to an embodiment of the present invention;

[0048] Figure 5 This is a scanning electron microscope image of bulk niobium selenide according to an embodiment of the present invention;

[0049] Figure 6 This is a scanning electron microscope image of the niobium selenide nanosheet according to an embodiment of the present invention.

[0050] Description of Reference Numerals

[0051] 1. Antenna; 2. Ammonia molecule; 3. Capacitor-inductor wireless passive sensor; 4. Flexible substrate; 5. Inductor coil; 6. Niobium selenide nanosheet sensitive film; 7. Interdigital electrode; 8. Niobium selenide nanosheet; 9. Bulk niobium selenide. DETAILED DESCRIPTION

[0052] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed below.

[0053] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0054] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0055] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0056] In the description of the present invention, "several" means more than one, "many" means more than two, "greater than", "less than", "exceed", etc. are understood to exclude the number itself, and "above", "below", "within", etc. are understood to include the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0057] In this article, "optionally", "optional", "optional" means optional, that is, it means to be selected from any of the two parallel solutions of "yes" or "no". If there are multiple "optional" in a technical solution, unless otherwise specified and there is no contradiction or mutual restriction, each "optional" is independent. In this application, the descriptions such as "optionally contain" and "optionally include" mean "contain or not contain".

[0058] In the present application, when it comes to a numerical interval (i.e., a numerical range), unless otherwise specified, the distribution of the optional numerical values ​​in the numerical interval is considered to be continuous, and includes the two numerical endpoints (i.e., the minimum and maximum values) of the numerical interval, and each numerical value between the two numerical endpoints. Unless otherwise specified, when the numerical interval only refers to an integer in the numerical interval, it includes the two endpoint integers of the numerical range, and each integer between the two endpoints, which is equivalent to directly listing each integer. When multiple numerical ranges are provided to describe features or characteristics, these numerical ranges can be combined. In other words, unless otherwise specified, the numerical range disclosed in the present application should be understood to include any and all sub-ranges included therein. The "numerical value" in the numerical interval can be any quantitative value, such as a number, a percentage, a ratio, etc. "Numerical interval" allows for a broad range of quantitative intervals such as percentage intervals, ratio intervals, and ratio intervals.

[0059] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0060] The embodiment of the present application provides a human exhaled gas detection system to solve the following problems existing in the ammonia sensor used to detect ammonia concentration in the prior art: the current ammonia sensor is of a wired type and needs to be connected to a professional instrument to test the sensor signal, which limits the portability of the detection system. The human exhaled gas detection system will be described below in conjunction with the accompanying drawings.

[0061] The human exhaled gas detection system provided in the embodiment of the present application is exemplary, please refer to Figure 1 As shown, Figure 1 The human exhaled gas detection system of the present application can be used to detect the ammonia concentration in the human exhaled gas, which can indirectly reflect the degree of kidney damage, thereby guiding corresponding treatment and management measures.

[0062] In order to more clearly illustrate the structure of the human exhaled gas detection system, the human exhaled gas detection system will be introduced below with reference to the accompanying drawings.

[0063] For example, see Figure 1 As shown, Figure 1The structure diagram of a human exhaled gas detection system according to an embodiment of the present invention is a human exhaled gas detection system, comprising an antenna 1 and a capacitive-inductive wireless passive sensor 3. The capacitive-inductive wireless passive sensor 3 comprises a flexible substrate 4, an inductive coil 5, a niobium selenide nanosheet sensitive film 6 and a forked electrode 7. The inductive coil 5 is connected to the flexible substrate 4. The niobium selenide nanosheet sensitive film 6 covers the forked electrode 7 to form an ammonia sensitive electrode. The ammonia sensitive electrode is connected to the inductive coil 5 to form a capacitive-inductive wireless passive sensor 3, see Figure 2 As shown, Figure 2 The structure diagram of the capacitor-inductor wireless passive sensor 3 based on the niobium selenide nanosheet 8 according to one embodiment of the present invention is shown. The antenna 1 can be connected to the capacitor-inductor wireless passive sensor 3 by wireless signal through the electromagnetic coupling effect to detect the return loss of the capacitor-inductor wireless passive sensor 3 and thus detect the ammonia concentration in the exhaled gas.

[0064] In some embodiments, the inductor 5 is in a U-shaped multi-turn structure from the inside to the outside.

[0065] In some embodiments, the antenna 1 is in a ring structure. Preferably, the size of the ring structure of the antenna 1 is slightly larger than the size of the inductor 5, so that the antenna 1 and the inductor 5 can cooperate with each other to perform electromagnetic coupling effect.

[0066] An embodiment of the present application also provides a method for preparing a human exhaled gas detection system.

[0067] It should be noted that, in this article, unless otherwise specified, each reaction step can be carried out in the order described herein, or can be carried out in a non-sequential manner. For example, other steps may be included between each reaction step, and the order of the reaction steps may also be appropriately swapped. This can be determined by the technician based on conventional knowledge and experience. Preferably, the reaction method herein is carried out sequentially.

[0068] A method for preparing a human exhaled gas detection system comprises the following steps:

[0069] Disperse bulk niobium selenide 9 in a first dispersing solvent, and obtain a mixed solution by water bath ultrasound; subject the mixed solution to ultrasonic crushing to peel off bulk niobium selenide 9 to obtain a niobium selenide solution; centrifuge the niobium selenide solution and collect the supernatant; centrifuge the supernatant to collect the precipitated niobium selenide powder, and wash the niobium selenide powder with a cleaning solution for at least three times, collect the washed sample, and freeze-dry the sample to obtain niobium selenide nanosheets 8; add the niobium selenide nanosheets 8 to a second dispersing solvent, and subject it to ultrasonic treatment to form a uniformly distributed niobium selenide nanosheet 8 solution for later use.

[0070] The first mask having the patterned coil channel is covered on the flexible substrate 4 , and the inductor 5 is prepared on the flexible substrate 4 through the patterned coil channel of the first mask.

[0071] Conductive silver paste is filled into the connection holes at the two ends of the inductor coil 5 on the flexible substrate 4 and dried to form conductive connecting parts.

[0072] The second mask having the patterned electrode channels is covered on the flexible substrate 4 , and the interdigitated electrodes 7 are prepared on the flexible substrate 4 through the patterned electrode channels of the second mask.

[0073] The niobium selenide nanosheet 8 solution is evenly arranged on the interdigital electrode 7 and dried to form a niobium selenide nanosheet sensitive film 6. The niobium selenide nanosheet sensitive film 6 and the interdigital electrode 7 constitute an ammonia sensitive electrode. The two electrodes of the interdigital electrode 7 are respectively connected to the two ends of the inductor 5 through conductive connectors.

[0074] In some of the embodiments, the mass volume ratio of the bulk niobium selenide 9 to the first dispersion solvent is (100 mg~200 mg): (100 mL~200 mL). For example, in one specific example, the mass volume ratio of the bulk niobium selenide 9 to the first dispersion solvent is 100 mg:100 mL. In another specific example, the mass volume ratio of the bulk niobium selenide 9 to the first dispersion solvent is 100 mg:200 mL. In another specific example, the mass volume ratio of the bulk niobium selenide 9 to the first dispersion solvent is 200 mg:100 mL. It is not difficult to understand that in other specific examples, the mass volume ratio of the bulk niobium selenide 9 to the first dispersion solvent can also be 150 mg:100 mL, 150 mg:200 mL or other ratios and ranges.

[0075] In some embodiments, the first dispersing solvent includes 55% ethanol.

[0076] In some embodiments, the time of water bath sonication is 25 min to 40 min. For example, in one specific example, the time of water bath sonication is 25 min. In another specific example, the time of water bath sonication is 40 min. It is not difficult to understand that in other specific examples, the time of water bath sonication can also be 28 min, 30 min, 35 min or other ratios and ranges.

[0077] In some embodiments, during ultrasonic crushing, the mixed solution is placed in an ultrasonic crusher, and the bulk niobium selenide 9 is peeled off at an ultrasonic power of 200 W to 300 W for 3 h to 4 h to obtain a niobium selenide solution. For example, in one specific example, the ultrasonic power is 200 W. In another specific example, the ultrasonic power is 300 W. It is not difficult to understand that in other specific examples, the ultrasonic power can also be 230 W, 250 W, 280 W or other ratios and ranges.

[0078] In some of the embodiments, when the niobium selenide solution is centrifuged, the niobium selenide solution is centrifuged in a centrifuge at 1500 rpm to 2000 rpm for 15 min to 20 min.

[0079] In some embodiments, when the supernatant is centrifuged, the supernatant is placed in a centrifuge and centrifuged at 8000 rpm to 10000 rpm for 15 min to 20 min.

[0080] In some embodiments, the cleaning solution comprises 95% ethanol.

[0081] In some embodiments, during freeze drying, the sample collected and washed in the step is freeze dried for at least 12 h.

[0082] In some of the embodiments, the mass volume ratio of the niobium selenide nanosheets 8 to the second dispersion solvent is (10 mg~20 mg): (5 mL~10 mL). For example, in one specific example, the mass volume ratio of the niobium selenide nanosheets 8 to the second dispersion solvent is 10 mg:5 mL. In another specific example, the mass volume ratio of the niobium selenide nanosheets 8 to the second dispersion solvent is 10 mg:10 mL. In another specific example, the mass volume ratio of the niobium selenide nanosheets 8 to the second dispersion solvent is 20 mg:5 mL. It is not difficult to understand that in other specific examples, the mass volume ratio of the niobium selenide nanosheets 8 to the second dispersion solvent can also be 15 mg:5 mL, 15 mg:10 mL or other ratios and ranges.

[0083] In some embodiments, the second dispersing solvent includes analytical grade ethanol.

[0084] In some embodiments, when ultrasonic treatment is performed to form a uniformly distributed solution of niobium selenide nanosheets 8, the ultrasonic time is 15 min to 30 min. For example, in one specific example, the ultrasonic time is 15 min. In another specific example, the ultrasonic time is 30 min. It is not difficult to understand that in other specific examples, the ultrasonic time can also be 18 min, 20 min, 25 min or other ratios and ranges.

[0085] In some embodiments, the inductor 5 is prepared by the following steps:

[0086] A first copper metal layer is magnetron sputtered on the flexible substrate 4 through the patterned coil channel of the first mask, a second copper metal layer with a thickness of 8 μm~10 μm is electroplated on the first copper metal layer, a first nickel metal layer with a thickness of 2 μm~3 μm is electroplated on the second copper metal layer, and a first gold metal layer with a thickness of 0.05 μm~0.1 μm is electroplated on the first nickel metal layer.

[0087] In some embodiments, the conductive paste includes silver paste.

[0088] In some embodiments, when drying to form the conductive connection member, the drying is performed at a temperature of 60° C. to 70° C. for at least 30 minutes. For example, in a specific example, the drying condition is 60° C. for 30 minutes.

[0089] In some embodiments, the preparation of the interdigitated electrodes 7 on the flexible substrate 4 through the patterned electrode channels of the second mask includes the following steps:

[0090] A third copper metal layer is magnetron sputtered on the flexible substrate 4 through the patterned electrode channel of the second mask, a fourth copper metal layer with a thickness of 8 μm~10 μm is electroplated on the third copper metal layer, a second nickel metal layer with a thickness of 2 μm~3 μm is electroplated on the fourth copper metal layer, and a second gold metal layer with a thickness of 0.05 μm~0.1 μm is electroplated on the second nickel metal layer to obtain the interdigitated electrode 7.

[0091] It should be noted that the preparation methods and preparation processes of the above-mentioned first copper metal layer and the third copper metal layer may be the same or different, and the thicknesses of the first copper metal layer and the third copper metal layer may be the same or different. The preparation methods and preparation processes of the above-mentioned second copper metal layer and the fourth copper metal layer may be the same or different, and the thicknesses of the second copper metal layer and the fourth copper metal layer may be the same or different. The preparation methods and preparation processes of the above-mentioned first nickel metal layer and the second nickel metal layer may be the same or different, and the thicknesses of the first nickel metal layer and the second nickel metal layer may be the same or different. The preparation methods and preparation processes of the above-mentioned first gold metal layer and the second gold metal layer may be the same or different, and the thicknesses of the first gold metal layer and the second gold metal layer may be the same or different.

[0092] In some embodiments, the niobium selenide nanosheet 8 solution is uniformly disposed on the interdigital electrodes 7 and dried to form the niobium selenide nanosheet sensitive film 6, which includes the following steps: using inkjet printing technology to uniformly print the niobium selenide nanosheet 8 solution on the interdigital electrodes 7.

[0093] In some embodiments, when drying to form the niobium selenide nanosheet sensitive film 6, the drying temperature is 20°C-30°C.

[0094] An embodiment of the present application also provides a method for detecting human exhaled gas.

[0095] A method for detecting human exhaled gas, using the above-mentioned human exhaled gas detection system, or the human exhaled gas detection system prepared by the above-mentioned preparation method, comprises the following steps:

[0096] See also Figure 3 As shown, Figure 3 This is a test schematic diagram of a capacitor-inductor wireless passive sensor 3 based on niobium selenide nanosheets 8 according to an embodiment of the present invention. A human exhaled gas detection system is placed in the gas to be tested. Ammonia molecules 2 in the gas to be tested provide electrons to the niobium selenide nanosheets 8 material on the niobium selenide nanosheet sensitive film 6 of the human exhaled gas detection system, causing the conductivity of the niobium selenide nanosheet sensitive film 6 to change, and causing the impedance of the capacitor-inductor wireless passive sensor 3 based on the niobium selenide nanosheet sensitive film 6 to change, so that the return loss S11 of the capacitor-inductor wireless passive sensor 3 changes, and the control antenna 1 and the capacitor-inductor wireless passive sensor 3 are connected by wireless signals through the electromagnetic coupling effect, so as to detect the return loss S11 of the capacitor-inductor wireless passive sensor 3, and detect the ammonia concentration in the gas to be tested based on the return loss S11. The above-mentioned human exhaled gas detection system is small in size, compact in structure, low in cost, does not require professional operation and is highly portable. The present application can be used to detect the ammonia concentration in human exhaled gas to indirectly reflect the degree of damage to kidney function, thereby guiding corresponding treatment and management measures.

[0097] Example 1

[0098] This embodiment 1 provides a human exhaled gas detection system, and a method for preparing the human exhaled gas detection system is prepared by the following method.

[0099] See also Figure 4 As shown, Figure 4 Schematic diagram of the preparation process of the capacitive-inductive wireless passive sensor 3 based on the niobium selenide nanosheet 8 of Example 1. A method for preparing a human exhaled gas detection system comprises the following steps:

[0100] Step S1, dispersing 150 mg of bulk niobium selenide 9 in 100 mL of a first dispersing solvent, 55% ethanol, and performing water bath ultrasonication for 25 min to obtain a mixed solution, wherein: Figure 5 As shown, Figure 5 This is a scanning electron microscope image of bulk niobium selenide 9 of Example 1.

[0101] Step S2: placing the mixed solution of step S1 in an ultrasonic crusher, and exfoliating the bulk niobium selenide 9 at an ultrasonic power of 200 W for 4 h to obtain a niobium selenide solution.

[0102] Step S3, centrifuging the niobium selenide solution in a centrifuge at 2000 rpm for 15 min, and collecting the supernatant.

[0103] Step S4, placing the supernatant of step S3 in a centrifuge and centrifuging at 10000 rpm for 15 min, collecting the precipitate niobium selenide powder, and washing the niobium selenide powder three times with a cleaning solution of 95% ethanol, and collecting the washed sample.

[0104] Step S5: freeze-dry the washed sample collected in step S4 for 12 h to obtain niobium selenide nanosheets 8, see Figure 6 As shown, Figure 6 This is a scanning electron microscope image of the niobium selenide nanosheet 8 of Example 1.

[0105] Step S6: 10 mg of the niobium selenide nanosheets 8 prepared in step S5 is placed in 5 mL of the second dispersing solvent, analytical pure ethanol, and ultrasonicated for 15 min to form a uniformly distributed niobium selenide nanosheet 8 solution for later use.

[0106] Step S7, magnetron sputtering a first copper metal layer on the flexible substrate 4 through the patterned coil channel of the first mask, electroplating a second copper metal layer with a thickness of 10 μm on the first copper metal layer, electroplating a first nickel metal layer with a thickness of 3 μm on the second copper metal layer, and electroplating a first gold metal layer with a thickness of 0.05 μm on the first nickel metal layer.

[0107] Step S8: Fill the connection holes at the two ends of the inductor 5 on the flexible substrate 4 with conductive silver paste, and dry them at 60° C. for 30 min to form conductive connectors. Figure 4 The positions of the two circular holes on the flexible substrate 4.

[0108] Step S9, magnetron sputtering a third copper metal layer on the flexible substrate 4 through the patterned electrode channel of the second mask, electroplating a fourth copper metal layer with a thickness of 10 μm on the third copper metal layer, electroplating a second nickel metal layer with a thickness of 3 μm on the fourth copper metal layer, and electroplating a second gold metal layer with a thickness of 0.05 μm on the second nickel metal layer to obtain the interdigitated electrode 7.

[0109] Step S10, using inkjet printing technology to uniformly print the niobium selenide nanosheet 8 solution prepared in step S6 on the interdigital electrode 7, and drying at 20°C to form a niobium selenide nanosheet sensitive film 6, the niobium selenide nanosheet sensitive film 6 and the interdigital electrode 7 form an ammonia sensitive electrode, the two electrodes of the interdigital electrode 7 are respectively connected to the two ends of the inductor 5 through conductive connectors, the ammonia sensitive electrode is connected to the inductor 5 to form a capacitor-inductor wireless passive sensor 3, the capacitor-inductor wireless passive sensor 3 see Figure 2 The human exhaled gas detection system prepared in Example 1 is shown in FIG. Figure 1 shown.

[0110] Example 2

[0111] This embodiment 2 provides a human exhaled gas detection system, and a method for preparing the human exhaled gas detection system is prepared by the following method.

[0112] A method for preparing a human exhaled gas detection system comprises the following steps:

[0113] Step S1, dispersing 200 mg of bulk niobium selenide 9 in 200 mL of a first dispersing solvent, 55% ethanol, and subjecting the mixture to water bath ultrasound for 40 min to obtain a mixed solution.

[0114] Step S2: placing the mixed solution of step S1 in an ultrasonic crusher, and exfoliating the bulk niobium selenide 9 at an ultrasonic power of 300 W for 3 h to obtain a niobium selenide solution.

[0115] Step S3, centrifuging the niobium selenide solution in a centrifuge at 1500 rpm for 20 min, and collecting the supernatant.

[0116] Step S4: Place the supernatant of step S3 in a centrifuge and centrifuge at 8000 rpm for 20 min, collect the precipitate niobium selenide powder, and wash the niobium selenide powder three times with a cleaning solution of 95% ethanol, and collect the washed sample.

[0117] Step S5: freeze-dry the washed sample collected in step S4 for 12 h to obtain niobium selenide nanosheets 8.

[0118] Step S6: Take 20 mg of the niobium selenide nanosheets 8 prepared in step S5 and put it into 10 mL of the second dispersing solvent, analytical pure ethanol, and perform ultrasonic treatment for 30 min to form a uniformly distributed niobium selenide nanosheet 8 solution for later use.

[0119] Step S7, magnetron sputtering a first copper metal layer on the flexible substrate 4 through the patterned coil channel of the first mask, electroplating a second copper metal layer with a thickness of 10 μm on the first copper metal layer, electroplating a first nickel metal layer with a thickness of 3 μm on the second copper metal layer, and electroplating a first gold metal layer with a thickness of 0.05 μm on the first nickel metal layer.

[0120] Step S8, filling the connection holes at the two ends of the inductor 5 on the flexible substrate 4 with conductive silver paste, and drying at 70° C. for 30 min to form conductive connectors.

[0121] Step S9, magnetron sputtering a third copper metal layer on the flexible substrate 4 through the patterned electrode channel of the second mask, electroplating a fourth copper metal layer with a thickness of 8 μm on the third copper metal layer, electroplating a second nickel metal layer with a thickness of 2 μm on the fourth copper metal layer, and electroplating a second gold metal layer with a thickness of 0.1 μm on the second nickel metal layer to obtain the interdigitated electrode 7.

[0122] Step S10, using inkjet printing technology to uniformly print the niobium selenide nanosheet 8 solution prepared in step S6 on the interdigital electrode 7, and drying at 30°C to form a niobium selenide nanosheet sensitive film 6, the niobium selenide nanosheet sensitive film 6 and the interdigital electrode 7 form an ammonia sensitive electrode, the two electrodes of the interdigital electrode 7 are respectively connected to the two ends of the inductor 5 through conductive connectors, the ammonia sensitive electrode is connected to the inductor 5 to form a capacitor-inductor wireless passive sensor 3, the capacitor-inductor wireless passive sensor 3 see Figure 2 The human exhaled gas detection system prepared in Example 1 is shown in FIG. Figure 1 shown.

[0123] Example 3

[0124] This embodiment 3 provides a human exhaled gas detection system, and the preparation method of the human exhaled gas detection system is prepared by the following method.

[0125] A method for preparing a human exhaled gas detection system comprises the following steps:

[0126] Step S1: Disperse 100 mg of bulk niobium selenide 9 in 100 mL of a first dispersing solvent, 55% ethanol, and perform water bath ultrasound for 25 min to obtain a mixed solution.

[0127] Step S2: placing the mixed solution of step S1 in an ultrasonic crusher, and exfoliating the bulk niobium selenide 9 at an ultrasonic power of 200 W for 3 h to obtain a niobium selenide solution.

[0128] Step S3, centrifuging the niobium selenide solution in a centrifuge at 1500 rpm for 15 min, and collecting the supernatant.

[0129] Step S4: Place the supernatant of step S3 in a centrifuge and centrifuge at 8000 rpm for 15 min, collect the precipitate niobium selenide powder, and wash the niobium selenide powder three times with a cleaning solution of 95% ethanol, and collect the washed sample.

[0130] Step S5: freeze-dry the washed sample collected in step S4 for 12 h to obtain niobium selenide nanosheets 8.

[0131] Step S6: 10 mg of the niobium selenide nanosheets 8 prepared in step S5 is placed in 5 mL of the second dispersing solvent, analytical pure ethanol, and ultrasonicated for 15 min to form a uniformly distributed niobium selenide nanosheet 8 solution for later use.

[0132] Step S7, magnetron sputtering a first copper metal layer on the flexible substrate 4 through the patterned coil channel of the first mask, electroplating a second copper metal layer with a thickness of 10 μm on the first copper metal layer, electroplating a first nickel metal layer with a thickness of 3 μm on the second copper metal layer, and electroplating a first gold metal layer with a thickness of 0.05 μm on the first nickel metal layer.

[0133] Step S8, filling the connection holes at the two ends of the inductor 5 on the flexible substrate 4 with conductive silver paste, and drying at 60° C. for 30 min to form conductive connectors.

[0134] Step S9, magnetron sputtering a third copper metal layer on the flexible substrate 4 through the patterned electrode channel of the second mask, electroplating a fourth copper metal layer with a thickness of 10 μm on the third copper metal layer, electroplating a second nickel metal layer with a thickness of 3 μm on the fourth copper metal layer, and electroplating a second gold metal layer with a thickness of 0.05 μm on the second nickel metal layer to obtain the interdigitated electrode 7.

[0135] Step S10, using inkjet printing technology to uniformly print the niobium selenide nanosheet 8 solution prepared in step S6 on the interdigital electrode 7, and drying at 25°C to form a niobium selenide nanosheet sensitive film 6, the niobium selenide nanosheet sensitive film 6 and the interdigital electrode 7 form an ammonia sensitive electrode, the two electrodes of the interdigital electrode 7 are respectively connected to the two ends of the inductor 5 through a conductive connector, the ammonia sensitive electrode is connected to the inductor 5 to form a capacitor-inductor wireless passive sensor 3, the capacitor-inductor wireless passive sensor 3 see Figure 2 The human exhaled gas detection system prepared in Example 1 is shown in FIG. Figure 1 shown.

[0136] In summary, compared with the prior art, the human exhaled gas detection system of the present invention has the following beneficial effects:

[0137] (1) The wireless signal transmission characteristics based on the electromagnetic coupling effect of the present application can realize real-time monitoring of the ammonia concentration in the exhaled gas to be tested, with high detection efficiency and accurate detection results.

[0138] (2) The present application has a simple and compact structure, a very small overall size, good mobility, and is easy to carry. It can be used for personalized medical, testing and other services.

[0139] (3) The circuit of the present application is relatively simple and does not require external power supply. The manufacturing and use costs are relatively low. It can be deployed on a large scale and widely used, which can significantly reduce the detection cost.

[0140] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0141] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0142] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A human exhaled gas detection system, characterized in that: The invention comprises an antenna and a capacitor-inductor wireless passive sensor, wherein the capacitor-inductor wireless passive sensor comprises a flexible substrate, an inductor coil, a niobium selenide nanosheet sensitive film and interdigital electrodes, wherein the inductor coil is connected to the flexible substrate, the niobium selenide nanosheet sensitive film covers the interdigital electrodes to form an ammonia sensitive electrode, and the ammonia sensitive electrode is connected to the inductor coil to form the capacitor-inductor wireless passive sensor. The antenna can be connected to the capacitor-inductor wireless passive sensor through a wireless signal through an electromagnetic coupling effect to detect the return loss of the capacitor-inductor wireless passive sensor and thus detect the ammonia concentration in the exhaled gas.

2. The human exhaled gas detection system according to claim 1, characterized in that: The inductor coil is in a U-shaped multi-turn winding structure from the inside to the outside.

3. The human exhaled gas detection system according to claim 1, characterized in that: The antenna is in a ring structure.

4. A method for preparing a human exhaled gas detection system according to any one of claims 1 to 3, characterized in that: The steps include: Dispersing bulk niobium selenide in a first dispersing solvent, and performing water bath ultrasonication to obtain a mixed solution; performing ultrasonic crushing on the mixed solution to peel off bulk niobium selenide to obtain a niobium selenide solution; centrifuging the niobium selenide solution to collect a supernatant; centrifuging the supernatant to collect precipitated niobium selenide powder, and washing the niobium selenide powder at least three times with a cleaning solution, collecting a sample after washing, and freeze-drying the sample to obtain niobium selenide nanosheets; adding the niobium selenide nanosheets to a second dispersing solvent, and performing ultrasonic treatment to form a uniformly distributed niobium selenide nanosheet solution for standby use; Covering a first mask having a patterned coil channel on a flexible substrate, and preparing an inductor coil on the flexible substrate through the patterned coil channel of the first mask; Filling conductive silver paste into the connection holes at the two ends of the inductor coil on the flexible substrate, and drying to form conductive connecting parts; Covering a second mask having patterned electrode channels on a flexible substrate, and preparing interdigitated electrodes on the flexible substrate through the patterned electrode channels of the second mask; as well as The niobium selenide nanosheet solution is evenly disposed on the interdigital electrodes and dried to form a niobium selenide nanosheet sensitive film. The niobium selenide nanosheet sensitive film and the interdigital electrodes constitute an ammonia sensitive electrode. The two electrodes of the interdigital electrodes are respectively connected to the two ends of the inductor coil through the conductive connector.

5. The method for preparing the human exhaled gas detection system according to claim 4, characterized in that: The preparation method of the human exhaled gas detection system meets at least one of the following conditions: (1) The mass volume ratio of the bulk niobium selenide to the first dispersing solvent is (100 mg-200 mg): (100 mL-200 mL); (2) the first dispersing solvent includes 55% ethanol; (3) The water bath ultrasound time is 25 min~40 min; (4) During the ultrasonic crushing treatment, the mixed solution is placed in an ultrasonic crusher, and the bulk niobium selenide is peeled off at an ultrasonic power of 200 W to 300 W for 3 h to 4 h to obtain the niobium selenide solution; (5) When the niobium selenide solution is centrifuged, the niobium selenide solution is centrifuged in a centrifuge at 1500 rpm to 2000 rpm for 15 min to 20 min; (6) When the supernatant is centrifuged, the supernatant is placed in a centrifuge and centrifuged at 8000 rpm to 10000 rpm for 15 min to 20 min; (7) The cleaning solution comprises 95% ethanol; (8) During freeze drying, freeze-dry the sample collected and washed in step 1 for at least 12 hours; (9) The mass volume ratio of the niobium selenide nanosheets to the second dispersing solvent is (10 mg~20 mg): (5 mL~10 mL); (10) The second dispersing solvent comprises analytical grade ethanol; (11) When ultrasonic treatment is performed to form a uniformly distributed niobium selenide nanosheet solution, the ultrasonic time is 15 min~30 min.

6. The method for preparing the human exhaled gas detection system according to claim 5, characterized in that: The inductor coil is prepared by the following steps: A first copper metal layer is magnetron sputtered on the flexible substrate through the patterned coil channel of the first mask, a second copper metal layer with a thickness of 8 μm to 10 μm is electroplated on the first copper metal layer, a first nickel metal layer with a thickness of 2 μm to 3 μm is electroplated on the second copper metal layer, and a first gold metal layer with a thickness of 0.05 μm to 0.1 μm is electroplated on the first nickel metal layer.

7. The method for preparing the human exhaled gas detection system according to claim 5, characterized in that: The preparation method of the human exhaled gas detection system meets at least one of the following conditions: (1) The conductive paste includes silver paste; (2) When drying to form a conductive connection, dry at 60℃~70℃ for at least 30 minutes.

8. The method for preparing the human exhaled gas detection system according to claim 5, characterized in that: When preparing interdigitated electrodes on the flexible substrate through the patterned electrode channels of the second mask, the following steps are included: A third copper metal layer is magnetron sputtered on the flexible substrate through the patterned electrode channel of the second mask, a fourth copper metal layer with a thickness of 8 μm to 10 μm is electroplated on the third copper metal layer, a second nickel metal layer with a thickness of 2 μm to 3 μm is electroplated on the fourth copper metal layer, and a second gold metal layer with a thickness of 0.05 μm to 0.1 μm is electroplated on the second nickel metal layer to obtain an interdigitated electrode.

9. The method for preparing the human exhaled gas detection system according to claim 5, characterized in that: The preparation method of the human exhaled gas detection system meets at least one of the following conditions: (1) The niobium selenide nanosheet solution is uniformly disposed on the interdigital electrodes and dried to form a niobium selenide nanosheet sensitive film, comprising the following steps: using inkjet printing technology to uniformly print the niobium selenide nanosheet solution on the interdigital electrodes; (2) When drying to form the niobium selenide nanosheet sensitive film, the drying temperature is 20°C~30°C.

10. A method for detecting human exhaled gas, characterized in that: The human exhaled gas detection system according to any one of claims 1 to 3 or the preparation method according to any one of claims 4 to 9 comprises the following steps: A human exhaled gas detection system is placed in the gas to be tested, and ammonia molecules in the gas to be tested provide electrons to the niobium selenide nanosheet material on the niobium selenide nanosheet sensitive film of the human exhaled gas detection system, causing the conductivity of the niobium selenide nanosheet sensitive film to change, and causing the impedance of the capacitor-inductor wireless passive sensor based on the niobium selenide nanosheet sensitive film to change, so that the return loss S11 of the capacitor-inductor wireless passive sensor changes, and the wireless signal connection between the control antenna and the capacitor-inductor wireless passive sensor is achieved through the electromagnetic coupling effect, so as to detect the return loss S11 of the capacitor-inductor wireless passive sensor, and detect the ammonia concentration in the gas to be tested based on the return loss S11.

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