Press-type sweat component detection sensor and use method thereof

Abstract

The invention provides a pressing type sweat component detection sensor which comprises a silk-screen printing sensing layer, a patterned bonding layer, a hydrogel loading well and a palm pressing outer frame which are sequentially arranged from bottom to top, and the silk-screen printing sensing layer comprises detection electrodes corresponding to fingertips in position; a loading opening is formed in the position, aligned with the detection electrode, of the hydrogel loading well, the loading opening is filled with hydrogel, and the detection electrode is used for forming an electrochemical signal related to the content of a to-be-detected component in sweat during detection. The pressing type sweat component detection sensor has the capacity of rapidly and accurately detecting the level of components such as cortisol in fingertip sweat, and the cortisol level can be measured under various pressure scenes and the circadian rhythm of daily activities through the sensor.

Description

Technical Field

[0001] The present invention belongs to the field of sweat component detection, and in particular relates to a press-type sweat component detection sensor and a use method thereof, which can be used for cortisol detection. Background Art

[0002] Cortisol is an important steroid hormone. In human physiology, cortisol plays an important role in regulating a variety of physiological mechanisms, including carbohydrate metabolism, optimizing glucose concentration, and maintaining blood pressure. The secretion of cortisol in the body is also related to immune, cardiovascular, bone, kidney, and endocrine homeostasis. The fluctuation of cortisol concentration throughout the day is called the circadian rhythm. Cortisol levels are higher in the morning and gradually decrease at night. In addition to the circadian rhythm, multiple factors such as physical activity and long-term stress can also affect the secretion of cortisol in the body. Abnormal levels of cortisol in the body may suppress the immune system, inhibit inflammation, and reduce fat and amino acid concentrations. Physiologically, high cortisol concentrations are associated with Cushing's disease, which may cause symptoms such as fatigue, osteoporosis, and obesity. Reduced cortisol levels may cause Addison's disease. Lack of cortisol in the body may cause weight loss, lower blood pressure, fatigue, abdominal pain, and muscle weakness, leading to serious diseases such as heart attack, brain disease, and chronic depression. Therefore, the cortisol index is of great significance for monitoring human health in various scenarios such as daily life, exercise, physical work, and work.

[0003] Therefore, rapid, reliable and non-invasive detection of cortisol levels is of great significance for comprehensive self-monitoring, health management and personalized medicine. In order to quantify cortisol levels, common methods include psychological assessment, behavioral observation, physiological monitoring and biological indicator detection. Among them, psychology relies on self-assessment to fill out questionnaires or conduct interviews, while behavior studies daily habits or behavioral changes, which have the disadvantages of subjective conclusions and long-term observation. Physiology monitors changes in physical and biological indicators of the body, which is objective and real-time, and has therefore received widespread attention. Monitoring of physical indicators includes skin temperature, skin conductance, muscle activity, cardiopulmonary respiration rate and heart rate variability, eye contact and blood pressure, which can be used as potential indicators for real-time assessment of stress, emotions or fatigue. Biological monitoring, on the other hand, is the detection of the content of cortisol produced by the adrenal glands and diffused into the blood circulation through cells.

[0004] Existing technologies mainly use human blood samples to detect blood cortisol levels, which is an invasive method and is not conducive to the application of cortisol, which requires multiple measurements or real-time monitoring in daily life and different usage scenarios. In addition, most existing methods rely on large-scale equipment in hospitals or laboratories, including microplate readers, gas chromatography or liquid chromatography, etc. The equipment is expensive and complicated to operate; professional technicians are required; the sample processing time is long, and instant detection cannot be achieved. In addition, existing wearable cortisol sensors are usually based on slow and complex detection methods, which are difficult to meet the needs of daily health monitoring and stress management.

[0005] Wearable electrochemical sensors can detect cortisol levels in blood, interstitial fluid (ISF), sweat, and saliva.

[0006] Among them, blood and ISF are invasive or minimally invasive tests, which are not suitable for wearable devices to monitor cortisol levels on a daily basis. Sweat and saliva have attracted much attention as non-invasive test samples in recent years. However, the accuracy of saliva sampling may be affected by factors such as food, beverages, and oral hygiene. In addition, the concentration of cortisol in saliva fluctuates greatly, and the sensor needs to be accurately calibrated.

[0007] Sweat is a non-invasively obtained body fluid, which is suitable for the application of wearable devices. In addition, human sweat is a biological fluid discharged by the small sweat glands in the epidermis. It can be extracted on the surface of the human body, the sample content is rich, and the test is easily accepted by the subjects. Therefore, sweat-based wearable cortisol sensors have great potential.

[0008] Traditional blood cortisol detection methods usually require complex sample processing and analysis steps. These methods are not only time-consuming, but also costly and not suitable for real-time monitoring and on-site testing. Existing non-invasive sweat cortisol detection technology requires long-term wearing to obtain sufficient sweat when not exercising or the ambient temperature is low. The concentration of cortisol in sweat is low, and multiple measurements are required to obtain accurate results. However, the production of sweat is affected by many factors, such as ambient temperature, exercise, etc. Wearing for a long time to obtain sweat often leads to inaccurate results.

[0009] Therefore, how to efficiently collect sweat for rapid and accurate measurement of the levels of sweat components such as cortisol is a challenge faced by existing technologies. Summary of the invention

[0010] The object of the present invention is to provide a press-type sweat component detection sensor and a use method thereof, so as to efficiently collect sweat and improve the accuracy of sweat detection.

[0011] In order to achieve the above-mentioned purpose, the present invention provides a press-type sweat component detection sensor, comprising a screen-printed sensing layer, a patterned adhesive layer, a hydrogel loading well and a palm pressing outer frame arranged in sequence from bottom to top, the screen-printed sensing layer comprising a detection electrode corresponding to the position of the fingertip, the hydrogel loading well is provided with a loading opening at a position aligned with the detection electrode, the loading opening is filled with hydrogel, and the detection electrode is used to form an electrochemical signal related to the content of the component to be detected in sweat during detection.

[0012] The number of the detection electrodes is multiple groups, and each group of detection electrodes corresponds to the position of a fingertip.

[0013] The detection electrodes include a reference electrode, a working electrode and a counter electrode.

[0014] The working electrode is modified with antibodies of the component to be detected, and is used to form an electrochemical signal related to the content of the component to be detected in sweat during detection; the potential of the reference electrode is stable; and the counter electrode is used to form a circuit with the working electrode.

[0015] The antibody of the component to be detected includes a cortisol antibody, which is used to first combine with the cortisol in sweat and then with the enzyme-modified artificial cortisol, and then generate an electrochemical signal related to the content of cortisol in sweat through a substrate reaction.

[0016] The antibody of the component to be detected is modified on the modified working electrode in the following manner:

[0017] A1: Cyclic voltammetric deposition of carboxyl-functionalized pyrrole monomers for electropolymerization;

[0018] A2: Activate the working electrode with a mixed solution of EDC and NHS;

[0019] A2: Modify the antibody of the component to be detected onto the working electrode.

[0020] The screen-printed sensing layer further comprises a substrate, electrode wires, and an insulating packaging layer covering the electrode wires. The detection electrodes are connected to a back-end analysis device via the electrode wires.

[0021] The hydrogel is a PVA hydrogel and / or a porous hydrogel.

[0022] The screen-printed sensing layer and the patterned adhesive layer are replaceable; the hydrogel loading well and the palm pressing outer frame are both formed by printing with polymethyl methacrylate and bonded together by heat-cured epoxy resin glue.

[0023] In another aspect, the present invention provides a method for using a press-type sweat component detection sensor, comprising:

[0024] S1: Align and bond the screen-printed sensing layer, the patterned adhesive layer, the hydrogel loading well bonded to each other, and the palm pressing outer frame in sequence, wherein the screen-printed sensing layer includes a detection electrode corresponding to the position of the fingertip, to obtain a press-type sweat component detection sensor, wherein the hydrogel loading well is provided with a loading opening at a position aligned with the detection electrode, the loading opening is filled with hydrogel, and the detection electrode is used to form an electrochemical signal related to the content of the component to be detected in the sweat during detection; the detection electrode is connected to a back-end analysis device through an electrode wire;

[0025] S2: placing the palm in the palm pressing outer frame, wherein the fingertips are in contact with the area corresponding to the detection electrode, so that the sweat is guided to the surface of the detection electrode through the hydrogel in the hydrogel loading well, and the components to be detected in the sweat are combined with the working electrode;

[0026] S3: removing the screen-printed sensing layer to detect the electrochemical signal formed on the detection electrode and related to the content of the component to be detected in the sweat.

[0027] The press-type sweat component detection sensor of the present invention has the ability to quickly and accurately detect components in fingertip sweat, such as cortisol levels, and can be used to measure cortisol levels in various stress scenarios and the circadian rhythm of daily activities. In addition, the present invention provides an effective method for using a press-type sweat component detection sensor for non-invasive, real-time stress monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 1 is an overall structural diagram of a press-type sweat component detection sensor according to an embodiment of the present invention.

[0029] Figure 2 Yes Figure 1 An exploded view of a press-type sweat component detection sensor is shown.

[0030] Figure 3 Yes Figure 1 The electrode structure distribution diagram of the screen-printed sensing layer of the press-type sweat component detection sensor is shown.

[0031] Figure 4 The distribution diagram of the electrode structure on each fingertip of the screen-printed sensing layer.

[0032] Figure 5 Yes Figure 1 The schematic diagram of the structure of the patterned adhesive layer of the press-type sweat component detection sensor is shown.

[0033] Figure 6 Yes Figure 1 Schematic diagram of the structure of the hydrogel loading well of the press-type sweat component detection sensor shown.

[0034] Figure 7 Yes Figure 1 The structure diagram of the palm pressing outer frame of the press-type sweat component detection sensor shown in FIG.

[0035] Figure 8 Yes Figure 1 Schematic diagram of the bonding structure of the hydrogel loading well and the palm pressing frame of the press-type sweat component detection sensor shown.

[0036] Fig. 9 This is a comparison of the electrochemical signal curves obtained under different cortisol concentrations. DETAILED DESCRIPTION

[0037] like Figure 1 and Figure 2 The figure shows a press-type sweat component detection sensor according to an embodiment of the present invention, which utilizes a five-finger press method to bring the fingertips into contact with corresponding detection electrodes, thereby achieving fast, simple and reliable sweat cortisol detection through fingertip touch.

[0038] like Figure 1 and Figure 2 As shown, the press-type sweat component detection sensor includes a screen-printed sensing layer 10, a patterned adhesive layer 20, a hydrogel loading well 30 and a palm pressing outer frame 40 arranged in sequence from bottom to top. The screen-printed sensing layer 10 and the patterned adhesive layer 20 are replaceable consumables, so they are replaced after a single use. The hydrogel loading well 30 and the palm pressing outer frame 40 are both obtained by 3D printing and can be reused many times.

[0039] The screen-printed sensing layer 10 is a low-cost, large-scale commercially-available screen-printed product. Figure 3 As shown, the screen-printed sensing layer 10 includes a substrate 11 , a detection electrode 12 and an electrode wire 13 corresponding to the position of the fingertip, and an insulating packaging layer 14 covering the electrode wire 13 .

[0040] In this embodiment, the substrate 11 is polyethylene terephthalate (PET).

[0041] There are multiple groups of detection electrodes 12, each group of detection electrodes corresponds to the position of a fingertip. In this embodiment, the screen-printed sensing layer 10 is provided with a group of detection electrodes 12 at the position corresponding to each fingertip, so the number of detection electrodes 12 is 5 groups to correspond to the distribution of five fingers.

[0042] Therefore, the number of detection electrodes in the present invention is 5, and through the 5 detection electrodes, the sweat of 5 fingertips of a single hand can be effectively collected, eliminating the problem of inaccurate detection caused by unstable sweating of a single fingertip. At the same time, the cortisol content finally detected is the average of the detection results of the 5-channel electrodes, eliminating the detection error of the single fingertip sweat result, and achieving the effect of single press and multiple measurements.

[0043] The detection electrodes 12 are used to form an electrochemical signal related to the content of the component to be detected in the sweat during detection. Each group of detection electrodes 12 is a three-electrode structure, including a reference electrode 121, a working electrode 122 and a counter electrode 123. The reference electrode 121, the working electrode 122 and the counter electrode 133 exchange charges in the solution system, and the voltage and current are mutually regulated.

[0044] The working electrode 122 is modified with antibodies of the component to be detected, so as to form an electrochemical signal related to the content of the component to be detected in sweat during detection.

[0045] In this embodiment, the working electrode 122 is modified with a cortisol antibody, which is used to first bind to the cortisol in the sweat, then to the enzyme-modified artificial cortisol, and then to generate an electrochemical signal related to the content of cortisol in the sweat through a substrate reaction. Specifically, when the cortisol antibody on the working electrode 122 binds to the cortisol in the fingertip sweat, the added enzyme-modified artificial cortisol (i.e., HRP-cortisol) will be captured by the unbound blank antibody, and then the redox substrate and HRP (peroxidase) are added to promote the substrate reaction, which will cause the reduction current to change, thereby realizing the competitive method of cortisol detection.

[0046] The antibody of the component to be detected is modified on the modified working electrode 122 in the following manner:

[0047] Step A1: performing cyclic voltammetric deposition of carboxyl functionalized pyrrole monomers, such as polyphthalamide (PPA), to perform electropolymerization to enhance the antibody modification strength;

[0048] Step A2: adding a mixed solution of 1-(3-Dimethylaminopropyl)-3-ethylcarbodiimide / N-hydroxysuccinimide (EDC / NHS) to the surface of the working electrode 122 to activate the working electrode 122;

[0049] Step A2: modifying the working electrode 122 with an antibody of the component to be detected (such as a cortisol antibody).

[0050] In this embodiment, the material of the working electrode 122 is carbon. 20 μl of a solution containing 5.0 mM (M means mole / liter, mol / L) carboxyl functionalized pyrrole monomer and 0.5 M KCl was dripped onto the surface of each working electrode 122, and electropolymerization was performed using cyclic voltammetry (CV), with a potential range of 0.0 to 0.85 V (relative to Ag / AgCl), a scan rate of 0.1 V / s, and 20 cycles. After polymerization, the electrode was rinsed with deionized water and air-dried. The electrode was immersed in a mixed solution (0.025 M MES, pH 5.0) containing 0.4 MEDC and 0.1 MSulfo-NHS, and reacted in a humid environment at room temperature for 35 minutes to achieve activation. After the reaction was completed, the electrode was rinsed with deionized water and dried. 10 μL of anti-cortisol antibody solution (100 μg / mL, MES buffer, pH 5.0) was dripped onto the surface of each activated electrode and incubated at room temperature for 90 minutes. Subsequently, blocking was performed for 1 hour using 1.0% BSA (0.01 M phosphate buffer, containing Tween 20, pH 7.4). After blocking, the electrode was rinsed with the same buffer solution.

[0051] Therefore, the present invention uses screen printing and electrode surface modification to capture the components to be tested in sweat through antibodies modified on the electrode surface, and then adds the enzyme-modified artificial components to be tested, and then detects the content of the components to be tested in sweat through a competitive method.

[0052] The potential of the reference electrode 121 is stable in the electrochemical experiment, so it can be used as a potential reference (-0.2V in this embodiment) applied to the working electrode 122 in the experiment. In this embodiment, the working electrode 122 and the counter electrode 123 are made of carbon, and the reference electrode 121 is made of Ag / AgCl (silver electrode covered with silver chloride).

[0053] The main function of the counter electrode 123 is to form a circuit with the working electrode 122 so that current flows through the working electrode 122 , thereby ensuring that the reaction being studied occurs on the working electrode 122 .

[0054] The detection electrode 12 is connected to a back-end analysis device (not shown) via an electrode wire 13 to read the components to be detected in the sweat. In this embodiment, the back-end analysis device can be a desktop electrochemical workstation or a small portable electrochemical workstation, which is used to input a set voltage signal to the working electrode to accelerate the enzymatic reaction of the electrochemical substrate and read the reduction current.

[0055] The electrode structure of the screen-printed sensing layer 10 is distributed as follows: Figure 3 and Figure 4As shown, the counter electrode 123 is arranged around the working electrode 122, and the reference electrode 121 is arranged at the gap formed when the counter electrode 123 surrounds the working electrode 122.

[0056] Figure 4 : is a distribution diagram of the electrode structure on each fingertip of the screen-printed sensing layer, wherein the red frame is the exposed portion of the electrode not covered by the insulating encapsulation layer 14, while the other areas are covered by the insulating encapsulation layer 14. The insulating encapsulation layer 14 is made by a screen printing process. The function of the insulating encapsulation layer 14 is to ensure that only the exposed electrode portion is modified when the artificial cortisol modified by the subsequent enzyme is applied to modify the electrode. In this embodiment, the insulating encapsulation layer 14 ensures that only the detection electrode 12 is exposed by covering it with insulating ink.

[0057] like Figure 5 As shown, the patterned adhesive layer 20 is used to bond the screen-printed sensing layer 10 to the hydrogel loading well layer 30. The outer contour of the patterned adhesive layer 20 matches the outer contour of the screen-printed sensing layer 10, and both are square contours. The patterned adhesive layer 20 is provided with a plurality of adhesive layer openings 21 that match the detection electrodes 12 of the screen-printed sensing layer 10, so as to allow sweat to penetrate into the detection electrodes 12.

[0058] Among them, the material of the patterned adhesive layer 20 is double-sided adhesive tape, preferably 3M PET substrate double-sided adhesive tape, with a thickness of 0.17mm. The adhesive layer opening 21 of the patterned adhesive layer 20 is obtained by cutting the double-sided adhesive tape using a plotter. The uniformity and consistency of the patterned adhesive layer 20 mainly depend on the selection of raw materials and software parameters of the plotter, such as movement speed, applied pressure and depth of the blade tip. After setting, the entire cutting and engraving process can be completed in a short time. In this embodiment, the plotter used is Silhouette Cameo 5, and the present invention uses a blade with a maximum lettering depth of 2mm, a movement speed of 5cm / s, and an applied pressure of 8gf.

[0059] like Figure 6 As shown, the hydrogel loading well 30 is provided with a loading opening 31 at a position aligned with the detection electrode 12, and the loading opening 31 is filled with hydrogel. The body of the hydrogel loading well 30 is obtained by 3D printing and is used for loading hydrogel.

[0060] After use, the hydrogel filled in the body of the hydrogel loading well 30 needs to be covered with a PET film on both sides of the hydrogel to prevent water loss. When the surface of the hydrogel is no longer moist, the hydrogel needs to be replaced.

[0061] In this embodiment, the hydrogel adopts a highly permeable, porous, sweat-absorbent polyvinyl alcohol (PVA) hydrogel, which utilizes the high hydrophilicity of the PVA hydrogel, especially targeting the high-density exocrine sweat glands on the fingertips, thereby achieving efficient collection of sweat generated on the fingertips.

[0062] In this embodiment, the hydrogel is a porous hydrogel. The modified porous hydrogel can improve the water absorption of the fingertip contact part, and the pore structure increases the surface area and internal space of the hydrogel, so that the fingertip sweat can quickly diffuse to the electrode surface below through the pores of the hydrogel. Therefore, in the press-type sweat component detection sensor of the present invention, when the fingertip touches the surface of the five-electrode fingertip sensing array, the fingertip sweat can be quickly absorbed by the porous hydrogel, and the cortisol content can be recognized through the electrochemical signal.

[0063] In this embodiment, the porous PVA hydrogel is prepared, specifically comprising:

[0064] Step B1: providing PVA powder (molecular weight of about 89,000), potassium hydroxide (KOH), sucrose and deionized water.

[0065] Step B2: preparing a hydrogel precursor solution containing PVA, KOH and sucrose, specifically comprising:

[0066] Step B21: PVA powder is dissolved in deionized water at a weight ratio of 1:10 to prepare a PVA solution.

[0067] Step B22: Take 10 g of PVA solution, add 14 g of KOH solution (using KOH powder, dissolved in deionized water at a weight ratio of 1:5) dropwise while stirring, and mix well.

[0068] Step B23: Add sucrose (2.6 g based on the total weight) to the above PVA solution and continue stirring until it is completely dissolved to form a hydrogel precursor solution.

[0069] In this solution, PVA is the basic component of the hydrogel. It is a polymer material with good water solubility. Its molecular structure contains a large number of hydroxyl groups (–OH). These hydroxyl groups can cross-link PVA molecules with water molecules through hydrogen bonding to form a three-dimensional network structure, thus turning into a gel. KOH is a strong base. Adding it to the PVA solution can adjust the pH value of the solution. The high pH value can promote the hydroxyl groups in the PVA molecules to form hydrogen bonds more easily. The molecular chain of PVA is relatively long, and due to its multiple hydroxyl groups, the molecular chains can interact through hydrogen bonds to form a certain physical cross-linked structure. However, KOH does not directly participate in the formation of the pore structure. At this time, sucrose is evenly distributed in the PVA solution as a physical template. Since sucrose itself does not participate in the cross-linking reaction, its existence is to occupy a certain space so that PVA forms a structure containing sucrose during the gelation process. When the PVA solution is dried and cross-linked, sucrose still maintains its original solid state and acts as a template, so that the PVA in the gel can only form a network structure around the sucrose. Therefore, the space occupied by sucrose will not be filled by PVA molecules, leaving the prototype of the pores.

[0070] Step B3: removing excess water from the hydrogel precursor solution and cross-linking to obtain a PVA hydrogel;

[0071] 15 g of the precursor solution was poured into a Petri dish with a diameter of about 9 cm. The Petri dish was placed in a vacuum desiccator to remove excess water and perform cross-linking until the weight of the precursor solution was reduced to 1 / 3 of the original.

[0072] Step B4: Remove sucrose and KOH to obtain porous PVA hydrogel.

[0073] In step B4, the cross-linked hydrogel was immersed in 0.1 M PBS buffer to remove the sucrose template and excess KOH until the hydrogel reached a neutral pH.

[0074] After drying and cross-linking, the hydrogel was washed with 0.1M PBS, and the sucrose gradually dissolved. Sucrose is water-soluble, so it is removed in the solution, and the space originally occupied by sucrose becomes pores in the gel. The shape, size, and distribution of these pores depend on the distribution of sucrose in the PVA solution and the size and shape of the sucrose particles. By controlling the amount and morphology of sucrose, the porosity and pore structure of the final hydrogel can be adjusted.

[0075] Step B5: Cut the prepared PVA hydrogel into a size and shape matching the detection electrode 12, and place a plurality of PVA hydrogels into the body of the hydrogel loading well 30 for subsequent use.

[0076] The porous PVA hydrogel prepared through this process can improve the water absorption of the fingertip contact part. The pore structure increases the surface area and internal space of the hydrogel, allowing the fingertip sweat to quickly diffuse through the pores of the hydrogel to the electrode surface below.

[0077] The structure of the palm pressing outer frame 40 is as follows Figure 7 As shown, it is a contoured structure, and the opening inside the palm pressing outer frame 40 is consistent with the overall shape of the palm and is aligned with the detection electrode 12.

[0078] In this embodiment, if Figure 8 As shown, the hydrogel loading well 30 and the palm pressing outer frame 40 are both formed by printing polymethyl methacrylate (PMMA), and the two are bonded together by heat-cured epoxy resin glue.

[0079] In summary, the press-type sweat component detection sensor of the present invention has the following significant advantages: (i) non-invasive press-type detection: the screen-printed electrodes of the present invention are arranged in the same way as the palm. After pressing with five fingers, the corresponding five detection electrodes can directly detect the sweat components of each fingertip, and the one-time multi-result detection brings efficient and accurate sweat component measurement results; (ii) fast and efficient sweat collection: the hydrogel loading well uses porous hydrogel to increase the specific surface area and the hydrophilicity of the hydrogel, so that the sweat collection efficiency is improved. The sweat of the fingertips after the finger touches can quickly reach the surface of the detection electrode in a short time, and the detection electrode can complete the detection of the test component such as cortisol within a few minutes; (iii) high specificity detection: by modifying the antibody of the test component on the surface of the screen-printed electrode, it can bind to the test component in sweat with high specificity. (iv) the sensor is simple in design and easy to operate, and is suitable for real-time pressure monitoring in daily life.

[0080] Based on the above-mentioned push-type sweat component detection sensor, the use method of the push-type sweat component detection sensor specifically includes:

[0081] Step S1: Align and bond the screen-printed sensing layer 10, the patterned adhesive layer 20, the hydrogel loading wells 30 bonded to each other, and the palm pressing outer frame 40 in sequence to obtain a press-type sweat component detection sensor; connect the detection electrode 12 of the screen-printed sensing layer 10 to the back-end analysis device through the electrode wire 13.

[0082] Step S2: Place the palm in the palm pressing frame 40 , with the fingertips in contact with the area corresponding to the detection electrode 12 , so that sweat is guided to the surface of the detection electrode 12 through the hydrogel in the hydrogel loading well 30 , and the components to be tested in the sweat are combined with the working electrode 122 .

[0083] Specifically, the components to be tested in sweat are combined with antibodies modified with the components to be tested on the surface of the electrode through antigen-antibody binding.

[0084] Step S3: removing the screen-printed sensing layer 10 to detect the electrochemical signal formed on the detection electrode 12 and related to the content of the component to be detected in the sweat.

[0085] In this embodiment, the component to be tested is cortisol, so step S3 specifically includes:

[0086] Step S31: HRP-cortisol is dropped onto the working electrode, and the labeled cortisol and the free cortisol circulating in the sample are allowed to compete at the fixed receptor free sites for 15 minutes.

[0087] Step S32: After binding HRP-cortisol, rinse the electrode with deionized water and dry the electrode with air blowing.

[0088] Step S33: 20 μl of UltraTMB solution was dripped onto the surface of each electrode, and amperometric measurement was performed at -0.2 V (relative to Ag / AgCl). The chronoamperometric measurement was run for 180 s until the current was stable. The obtained chronoamperometric detection result was the electrochemical signal curve.

[0089] Based on the electrochemical signal curves obtained under different cortisol concentrations, the electrochemical signal curves under different cortisol concentrations can be compared. The electrochemical signal curves obtained by using a cortisol standard solution with a concentration of 0.0–8.0 ng / ml to simulate sweat (0.01 M PBST, pH 7.4 solution dilution) are as follows: Fig. 9 As shown, the results of different colors in the figure represent the chronoamperometric responses of cortisol standard solutions with different concentrations.

[0090] These results show that the touch-based cortisol detection sensor has the ability to quickly and accurately detect cortisol levels in fingertip sweat, and this sensor can be used to measure cortisol levels under various stress scenarios and circadian rhythms of daily activities. In summary, the touch-based cortisol detection platform developed by the present invention provides an effective new method for non-invasive, real-time stress monitoring.

Claims

1. A press-type sweat component detection sensor, characterized in that: The invention comprises a screen-printed sensing layer, a patterned adhesive layer, a hydrogel loading well and a palm pressing outer frame which are arranged in sequence from bottom to top. The screen-printed sensing layer comprises a detection electrode corresponding to the position of the fingertip. The hydrogel loading well is provided with a loading opening at a position aligned with the detection electrode. The loading opening is filled with hydrogel. The detection electrode is used to form an electrochemical signal related to the content of the component to be detected in sweat during detection.

2. The press-type sweat component detection sensor according to claim 1, characterized in that: The number of the detection electrodes is multiple groups, and each group of detection electrodes corresponds to the position of a fingertip.

3. The press-type sweat component detection sensor according to claim 1, characterized in that: The detection electrodes include a reference electrode, a working electrode and a counter electrode.

4. The press-type sweat component detection sensor according to claim 3, characterized in that: The working electrode is modified with antibodies of the component to be detected, and is used to form an electrochemical signal related to the content of the component to be detected in sweat during detection; the potential of the reference electrode is stable; and the counter electrode is used to form a circuit with the working electrode.

5. The press-type sweat component detection sensor according to claim 4, characterized in that: The antibody of the component to be detected includes a cortisol antibody, which is used to first combine with the cortisol in sweat and then with the enzyme-modified artificial cortisol, and then generate an electrochemical signal related to the content of cortisol in sweat through a substrate reaction.

6. The press-type sweat component detection sensor according to claim 4, characterized in that: The antibody of the component to be detected is modified on the modified working electrode in the following manner: Step A1: performing cyclic voltammetric deposition of carboxyl-functionalized pyrrole monomers for electropolymerization; Step A2: activating the working electrode with a mixed solution of EDC and NHS; Step A2: Modify the antibody of the component to be detected onto the working electrode.

7. The press-type sweat component detection sensor according to claim 3, characterized in that: The screen-printed sensing layer further comprises a substrate, electrode wires, and an insulating packaging layer covering the electrode wires. The detection electrodes are connected to a back-end analysis device via the electrode wires.

8. The press-type sweat component detection sensor according to claim 1, characterized in that: The hydrogel is a PVA hydrogel and / or a porous hydrogel.

9. The press-type sweat component detection sensor according to claim 1, characterized in that: The screen-printed sensing layer and the patterned adhesive layer are replaceable; the hydrogel loading well and the palm pressing outer frame are both formed by printing with polymethyl methacrylate and bonded together by heat-cured epoxy resin glue.

10. A method for using a press-type sweat component detection sensor, characterized in that: include: Step S1: aligning and bonding the screen-printed sensing layer, the patterned adhesive layer, the hydrogel loading well bonded to each other, and the palm pressing outer frame in sequence, wherein the screen-printed sensing layer includes a detection electrode corresponding to the position of the fingertip, to obtain a press-type sweat component detection sensor, wherein the hydrogel loading well is provided with a loading opening at a position aligned with the detection electrode, wherein the loading opening is filled with hydrogel, and the detection electrode is used to form an electrochemical signal related to the content of the component to be detected in the sweat during detection; the detection electrode is connected to a back-end analysis device through an electrode wire; Step S2: placing the palm in the palm pressing outer frame, wherein the fingertips are in contact with the area corresponding to the detection electrode, so that the sweat is guided to the surface of the detection electrode through the hydrogel in the hydrogel loading well, and the components to be detected in the sweat are combined with the working electrode; Step S3: removing the screen-printed sensing layer to detect the electrochemical signal formed on the detection electrode and related to the content of the component to be detected in the sweat.

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