阅读说明：本技术 一种导纳式出汗率传感器的制备方法 (Preparation method of admittance type sweating rate sensor ) 是由 刘爱萍 吕子寒 魏磊 房国庆 程琳 于 2021-07-14 设计创作，主要内容包括：本发明揭示了一种导纳式出汗率传感器的制备方法,采用本发明实施例中所提供的方法,能够通过极其简单的器材以及步骤制备获得导纳式出汗率传感器,相应的传感器能够基于传感器电路中导纳的大小定量计算出出汗率,从而实现对汗液体征的量化分析。(The invention discloses a preparation method of an admittance type sweating rate sensor, by adopting the method provided by the embodiment of the invention, the admittance type sweating rate sensor can be prepared and obtained through extremely simple equipment and steps, and the corresponding sensor can quantitatively calculate the sweating rate based on the size of admittance in a sensor circuit, thereby realizing quantitative analysis of sweat signs.)

1. A method of making an admittance sweat rate sensor, comprising:

the method comprises the following steps: adhering the non-adhesive surface of the single-conductor copper foil tape to the adhesive surface of the weak adhesive tape, cutting the conductive surface of the single-conductor copper foil tape by adopting a laser cutting method to form an original electrode, removing copper foil materials except the original electrode by using tweezers, adhering a PET (polyethylene terephthalate) film to the adhesive surface of the copper foil tape to transfer the original electrode to the PET film, and exposing the conductive surface of the single-conductor copper foil tape to the outside, wherein the original electrode is in a ladder-shaped structure, the ladder-shaped structure comprises two sections of first electrodes which are arranged in parallel and three sections of second electrodes which are arranged in parallel at equal intervals, and the second electrodes are positioned between the two sections of the first electrodes and are orthogonal to the first electrodes;

step two: cutting a section of double-sided tape corresponding to the original electrode, cutting the double-sided tape by laser, and forming a microfluidic channel extending in a direction parallel to the first electrode in the center of one surface of the double-sided tape;

step three: adhering the adhesive surface of the single-conductive copper foil adhesive tape to one surface, provided with the microfluidic channel, of a double-sided adhesive tape, and enabling the microfluidic channel to be located in the center of the two sections of first electrodes;

step four: cutting a second electrode on the microfluidic channel by using laser, wherein a laser cutting track vertically bisects the second electrode, so that three pulse points are formed at the intersection of the laser cutting track and the second electrode, and the three pulse points divide the original electrode into a first detection electrode and a second detection electrode;

step five: and sealing the conductive surface of the single-conductive copper foil adhesive tape by using the adhesive surface of the single-sided adhesive tape, and attaching and sealing the surface, which is not provided with the micro-flow channel, of the double-sided adhesive tape by using a PET (polyethylene terephthalate) film, so as to obtain the admittance type perspiration rate sensor.

2. The method of claim 1, wherein the laser cutting is performed by a laser cutter.

3. The method of claim 1, wherein the conductive surface of the single copper foil tape is a copper foil material, and the adhesive surface of the single copper foil tape is insulated.

4. The method of claim 1, wherein the weak adhesive tape, the single-sided copper foil tape, the double-sided tape, and the single-sided tape has an adhesive surface that is less adhesive than the adhesive surfaces of the other types of tapes.

5. The method of claim 1, wherein the laser cut trace has a width less than the width of the microfluidic channel.

6. The method of claim 1, wherein said first sensing electrode and said second sensing electrode are rendered conductive after sweat has flowed through said microfluidic channel, thereby forming a differential admittance pulse.

7. The method of claim 6, wherein the microfluidic channel has a cross-sectional area A, the pulse points are spaced apart from each other by a distance L, and the sweat rate Qi ═ A x L)/(Δ tn-1 is determined by detecting the time at which the differential admittance pulse occurs and determining the time Δ tn and Δ tn-1 at which the sweat front reaches the two adjacent pulse points.

Technical Field

The invention belongs to the field of sensors, and particularly relates to a preparation method of an admittance type sweating rate sensor.

Background

A large amount of secretion solutes such as lactate, urea, sodium and potassium for maintaining skin hydration, mycoprotein, tissue protein, and enzyme inhibin antimicrobial peptide exist in human sweat. Besides basic functions of regulating body temperature and protecting skin tissues, abundant physiological information contained in the sweat is human health information resources which are not fully utilized all the time, and the sweat can reflect the health level of a human body to a certain extent and analyze potential diseases of the human body. Compared with the blood collection with impaling property, the collection of sweat is more convenient and noninvasive, can go on outside the human body in real time, and aseptic requirement to external environment during the collection is lower, so how to collect sweat secreted by sweat gland from the human body surface fast and efficiently without pollution is explored, and human body information is obtained therefrom to become the hot problem in recent years, and the sweat is expected to become more ideal health monitoring information base than the traditional blood sampling.

Sweat production is closely related to the physiological health of the human body, and insufficient accumulation of body fluids and electrolytes due to sweating during physical activity and heat stress increases cardiovascular stress, which in turn may lead to impairment of physical and cognitive abilities, i.e., dehydration. Mild or moderate dehydration may result in symptoms of thirst, dry mouth, decreased frequency of urination, dark urine color, dry skin, coolness, headache, and muscle spasm. Severe dehydration can be associated with symptoms of accelerated heartbeat, breathlessness, anuresis, drowsiness, lack of vitality, confusion or irritability or even fainting. Quantitative measurement/assessment of body water loss sweat rate is undoubtedly an important measurement parameter in the real-time monitoring of human dehydration. Athletes often do not adequately replenish lost perspiration in hot environments, resulting in reduced hypertonic blood volume, which in turn can lead to impaired athletic performance. Due to the large individual variation in sweat rate, personalized liquid replenishment strategies should be developed for the athlete's sweat removal status. In the existing sweat rate detection method, factors such as a patch sweat absorption method and a clothes weight increasing method which cannot control sweat evaporation are measured accurately, trace sweat can not be detected almost, and meanwhile, the defect that the sweat cannot be collected causes that subsequent analysis and detection cannot be carried out. The microfluidic method for collecting sweat is a popular method because of its advantages of easy operation, low cost, small size, etc.

Disclosure of Invention

The invention aims to provide a preparation method of an admittance type sweating rate sensor, by adopting the method provided by the embodiment of the invention, the admittance type sweating rate sensor can be prepared and obtained through extremely simple equipment and steps, and the corresponding sensor can quantitatively calculate the sweating rate based on the size of admittance in a sensor circuit, thereby realizing quantitative analysis of sweat signs.

The technical scheme for realizing the aim of the invention is as follows: a method of making an admittance sweat rate sensor, comprising:

the method comprises the following steps: adhering the non-adhesive surface of the single-conductor copper foil tape to the adhesive surface of the weak adhesive tape, cutting the conductive surface of the single-conductor copper foil tape by adopting a laser cutting method to form an original electrode, removing copper foil materials except the original electrode by using tweezers, adhering a PET (polyethylene terephthalate) film to the adhesive surface of the copper foil tape to transfer the original electrode to the PET film, and exposing the conductive surface of the single-conductor copper foil tape to the outside, wherein the original electrode is in a ladder-shaped structure, the ladder-shaped structure comprises two sections of first electrodes which are arranged in parallel and three sections of second electrodes which are arranged in parallel at equal intervals, and the second electrodes are positioned between the two sections of the first electrodes and are orthogonal to the first electrodes;

step two: cutting a section of double-sided tape corresponding to the original electrode, cutting the double-sided tape by laser, and forming a microfluidic channel extending in a direction parallel to the first electrode in the center of one surface of the double-sided tape;

step three: adhering the adhesive surface of the single-conductive copper foil adhesive tape to one surface, provided with the microfluidic channel, of a double-sided adhesive tape, and enabling the microfluidic channel to be located in the center of the two sections of first electrodes;

step four: cutting a second electrode on the microfluidic channel by using laser, wherein a laser cutting track vertically bisects the second electrode, so that three pulse points are formed at the intersection of the laser cutting track and the second electrode, and the three pulse points divide the original electrode into a first detection electrode and a second detection electrode;

step five: and sealing the conductive surface of the single-conductive copper foil adhesive tape by using the adhesive surface of the single-sided adhesive tape, and attaching and sealing the surface, which is not provided with the micro-flow channel, of the double-sided adhesive tape by using a PET (polyethylene terephthalate) film, so as to obtain the admittance type perspiration rate sensor.

Further, laser cutting is achieved through a laser cutting machine.

Furthermore, the conductive surface of the single-conductor copper foil tape is made of a copper foil material, and the surface of the single-conductor copper foil tape with the adhesive is insulated.

Further, in the weak adhesive tape, the single-lead copper foil tape, the double-sided tape and the single-sided tape, the adhesive surface of the weak adhesive tape has a weaker viscosity than the adhesive surfaces of other types of tapes.

Further, the width of the laser cutting track is smaller than that of the microfluidic channel.

Further, the first detection electrode and the second detection electrode are turned on after sweat flows through the microfluidic channel, so that a differential admittance pulse is formed.

Further, the cross-sectional area of the microfluidic channel is a, the distance between the pulse points is L, and the time Δ tn and Δ tn-1 when the sweat front reaches the two adjacent pulse points is determined by detecting the time when the differential admittance pulse occurs, so that the sweat generation rate Qi is (a × L)/(Δtn- Δ tn-1).

Compared with the prior art, the preparation method provided by the invention has the advantages that the copper foil is used as the electrode, the price is low, and the material is easy to obtain; the laser cutting machine is used for obtaining the micro-flow channel and the detection electrode for sweat circulation, has the advantages of simple and convenient manufacturing mode and high manufacturing speed, and can be used for large-scale production. Meanwhile, the admittance type perspiration rate sensor prepared by the invention is not influenced by electrolyte concentration, obtains a measurement result from the perspective of perspiration rate, and has the advantages of exquisite design and accurate measurement. In the preparation process, the mode of firstly transferring and then cutting is adopted to ensure the regularity and symmetry of the two parts of detection electrodes after cutting, and compared with the mode of firstly cutting and then transferring, the trouble of alignment operation is saved, thereby greatly improving the preparation efficiency and the measurement accuracy of the sensor.

Drawings

FIG. 1 is a schematic view of a scenario in which sweat flows through an admittance-type sweat rate sensor obtained by a manufacturing method of the present invention;

FIG. 2 is a theoretical analysis curve of admittance values when sweat flows through an admittance-type sweat rate sensor obtained by the preparation method of the present invention;

FIG. 3 is a theoretical analysis image of differential admittance as sweat flows through an admittance-type sweat rate sensor obtained using the fabrication method of the present invention;

FIG. 4 is a graphical representation of the sensor morphology change for an admittance sweat rate sensor made in accordance with the method of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantageous technical effects of the present invention clearer, the following describes in detail a method for manufacturing an admittance type sweat rate sensor and the corresponding advantageous effects thereof, which are disclosed by the present invention, with reference to the accompanying drawings and the detailed description. It should be understood that the embodiments described in this specification are only for the purpose of illustrating the invention and are not to be construed as limiting the invention, and the parameters, proportions and the like of the embodiments may be suitably selected without materially affecting the results.

Description of the principle of sweat rate detection: as shown in fig. 1, 4 a-4 f, sweat flows in from one end of the microfluidic channel 4, and undergoes the following processes: at time t0, sweat does not come into contact with the second electrode that has been cut, and the impedance between the first detection electrode and the second detection electrode is infinite, with an admittance of 0. At time t1, sweat flows to the first pulse point position, the sweat connects the cut second electrodes at both ends, and the admittance between the first detection electrode and the second detection electrode is increased to S1. At time t2, sweat flowed to the second pulse point location and the admittance between the first and second detection electrodes increased to 2S 1. By analogy, at time tn, the total admittance between the first detection electrode and the second detection electrode is nS 1. And the admittance values between the two electrodes are kept unchanged from the time tn-1 to the time tn, as shown in fig. 1 and fig. 2, the difference of admittance versus time is denoted as Δ Si ═ Si-1)/(Δ ti-1, where Si-1 is the difference between the admittances of the two adjacent sampling points, Δ ti-1 is the time difference between the two adjacent sampling points, and the variation law of the difference admittance is shown in fig. 3. The time when the sweat front reaches each pulse point is obtained by detecting the pulse generation time of the differential admittance, and if the cross-sectional area of the microfluidic channel is a and the distance between two adjacent pulse points is L, the sweat generation rate is Qi ═ a × L/(Δ tn-1).

In the preparation method of the admittance-type perspiration rate sensor, the required preparation equipment comprises a common double-sided adhesive tape, a single-sided adhesive tape, a weak adhesive tape (the viscosity of the adhesive surface of the weak adhesive tape is similar to that of the adhesive surface of the note paper, the weak adhesive tape only has a slight fixing effect and is easy to remove after being adhered), a single-sided copper foil conductive adhesive tape, a PET film and a laser cutting machine.

Referring to fig. 4, in one embodiment of the method for manufacturing an admittance type sweat rate sensor according to the present invention, the operation steps are as follows:

step 1, as shown in fig. 4(a), adhering the non-adhesive surface of the single-conductor copper foil tape to the adhesive surface of the weak adhesive tape, then cutting the conductive surface of the single-conductor copper foil tape by a laser cutting method to form an original electrode 1 (copper electrode), removing the copper foil material except the original electrode by using a pair of tweezers, and then adhering the PET film 2 to the adhesive surface of the copper foil tape to transfer the original electrode 1 onto the PET film 2, so as to expose the conductive surface of the single-conductor copper foil tape, wherein the original electrode is in a ladder-type structure, the ladder-type structure comprises two sections of first electrodes arranged in parallel and three sections of second electrodes arranged in parallel at equal intervals, and the second electrodes are positioned between the two sections of first electrodes and are orthogonal to the first electrodes.

Step 2, as shown in fig. 4(b), a section of double-sided tape 3 corresponding to the original electrode 1 is cut, the double-sided tape 3 is cut by laser, and a microfluidic channel 4 extending in a direction parallel to the first electrode is formed in the center of one surface of the double-sided tape 3.

And 3, as shown in fig. 4(c), adhering the surface with adhesive of the single copper foil tape to the surface with the microfluidic channel 4 on the double-sided tape 3, and positioning the microfluidic channel 4 at the central position of the two sections of first electrodes.

And 4, cutting the second electrode on the microfluidic channel 4 by using laser, wherein the laser cutting track 5 vertically bisects the second electrode, so as to form three pulse points 6(6-1/6-2/6-3) at the intersection of the laser cutting track 5 and the second electrode, and the three pulse points 6 divide the original electrode 1 into a first detection electrode (7-1) and a second detection electrode (7-2), as shown in fig. 4 (d).

And 5, sealing the conductive surface of the single-conductive copper foil tape by using the adhesive surface of the single-sided tape 8, and laminating and sealing the surface, which is not provided with the microfluidic channel 4, of the double-sided tape 3 by using a PET (polyethylene terephthalate) film 9, so as to obtain the admittance-type perspiration rate sensor.

In one embodiment of the preparation method, a laser cutting machine is adopted to realize laser cutting. In one embodiment of the preparation method of the invention, in the weak adhesive tape, the single-lead copper foil tape, the double-sided tape and the single-sided tape, the adhesive surface of the weak adhesive tape is weaker than the adhesive surfaces of other types of tapes.

In one embodiment of the preparation method of the present invention, the width of the laser cutting track is smaller than the width of the microfluidic channel, so that the first detection electrode and the second detection electrode are not conducted without intervention of sweat, and are conducted only when sweat flows through the microfluidic channel and passes over the at least one second electrode which is cut off, and the more second electrodes the sweat passes over, the higher the corresponding total admittance value is.

In one embodiment of the preparation method of the present invention, after sweat flows through the microfluidic channel, the first detection electrode and the second detection electrode can be conducted, so as to form a differential admittance. From the time information of the differential admittance, it is possible to determine at which pulse point position the most anterior end of the current sweat is located, thereby determining the value of the time at which the sweat crosses the corresponding second electrode.

In one embodiment of the preparation method of the present invention, the cross-sectional area of the microfluidic channel is a, the pulse points are spaced apart from each other by L, and the sweat generation rate Qi is (a × L)/(Δtn- Δ tn-1) by determining the time Δ tn and Δ tn-1 when the sweat front reaches the two adjacent pulse points by detecting the occurrence time of the differential admittance pulse.

According to the preparation method, the copper foil is used as the electrode, so that the price is low, and the material is easy to obtain; the laser cutting machine is used for obtaining the micro-flow channel and the detection electrode for sweat circulation, has the advantages of simple and convenient manufacturing mode and high manufacturing speed, and can be used for large-scale production. Meanwhile, the admittance type perspiration rate sensor prepared by the invention is not influenced by electrolyte concentration, obtains a measurement result from the perspective of perspiration rate, and has the advantages of exquisite design and accurate measurement. In the preparation process, the mode of firstly transferring and then cutting is adopted to ensure the regularity and symmetry of the two parts of detection electrodes after cutting, and compared with the mode of firstly cutting and then transferring, the trouble of alignment operation is saved, thereby greatly improving the preparation efficiency and the measurement accuracy of the sensor.