Friction nanogenerator and application thereof

Abstract

The application relates to the field of friction nanogenerators, in particular to a friction nanogenerator device and application thereof. The friction nanogenerator device comprises a detection base, a connecting bin, a reagent bin and a driving unit, the reagent bin is internally hollow and is provided with an open upper end, a first triboelectric sponge and a second triboelectric sponge are arranged in the reagent bin, the first triboelectric sponge is made of a polydimethylsiloxane material, and the second triboelectric sponge is made of a polydimethylsiloxane material which is subjected to a bromophenol blue citric acid impregnation treatment. The application provides a portable urine protein content detection device which is stable in signal, simple in structure, low in preparation cost and capable of realizing home self-detection of urine protein, and realizes the function of detecting specific disease markers through the electric signal intensity of double detection channels.

Description

Technical Field

[0001] This invention relates to the field of triboelectric nanogenerators, and more particularly to a triboelectric nanogenerator device and its applications. Background Technology

[0002] In recent years, the incidence of chronic kidney disease has been rapidly increasing worldwide. The gold standard for detecting kidney disease is renal biopsy, a method of vital importance for definitive diagnosis, guiding treatment, predicting prognosis, exploring pathogenesis, and assessing medical outcomes. However, it carries risks such as infection, bleeding, allergic reactions to anesthetics, and accidental damage to other organs. Therefore, early screening or diagnosis primarily relies on clinical manifestations such as edema, proteinuria, and hematuria. However, current healthcare measures are often delayed, and most diseases are not discovered until severe symptoms appear.

[0003] Urine, as a non-invasive and readily available clinical biochemical sample, offers unique advantages over blood and sweat, making it an ideal entry point for home health monitoring. Urine is abundant and unaffected by environmental temperature and humidity, and it contains a rich variety of metabolites. Detection of these metabolites allows for real-time monitoring of various diseases. Therefore, enabling home self-testing of urine samples will play a crucial role in the early warning and disease progression monitoring of related conditions.

[0004] However, it is unrealistic to rely on medical institutions to achieve continuous daily monitoring of urine protein in the general public. Currently, the most mature home urine protein testing method on the market is urine protein test strips. However, urine protein test strips can only achieve semi-quantitative detection, and they are easily affected by interference. The colorimetric reagent in the test strips is mainly sensitive to high-content albumin, but not to other types of proteins. Due to these factors, it is still a qualitative detection method.

[0005] In recent years, electronic biosensors have attracted widespread attention due to their high sensitivity, high integration, and ease of operation. To achieve specific and quantitative detection of disease biomarkers, including proteins, in urine, many excellent research groups both domestically and internationally have conducted related research in this field. While these achievements have become powerful tools for home urine testing, they still have shortcomings such as complex device structures, sophisticated microfabrication techniques for sensing materials or detection chips, and high costs. Summary of the Invention

[0006] In view of this, the present invention provides a triboelectric nanogenerator.

[0007] A triboelectric nanogenerator includes a detection base, a connecting chamber, a reagent chamber, and a drive unit. The reagent chamber is hollow inside and open at the top, and contains a first triboelectric sponge and a second triboelectric sponge. The first triboelectric sponge is made of polydimethylsiloxane material, and the second triboelectric sponge is made of polydimethylsiloxane material impregnated with bromophenol blue and citric acid. The connecting chamber is detachably mounted on the upper end of the reagent chamber, and the drive unit is detachably mounted on the upper end of the connecting chamber. The detection base is vertically disposed inside the connecting chamber, with its upper end extending out of the connecting chamber and connected to the drive unit. The lower end of the detection base is provided with the triboelectric unit. The drive unit drives the detection base to move up and down until the triboelectric unit approaches or moves away from the first and second triboelectric sponges. The triboelectric unit is externally connected to a wire.

[0008] Furthermore, the reagent compartment includes a material placement section and a handheld section. The material placement section has a rectangular structure, is hollow inside and open at the top. A partition is vertically provided in the middle of the material placement section. The first triboelectric sponge and the second triboelectric sponge are respectively disposed on both sides of the partition. The handheld section is fixed to one side of the material placement section. The connecting compartment is slidably connected to the material placement section.

[0009] Furthermore, the driving unit includes a housing body, an impact rod, and a driving assembly. The housing body is a cylindrical structure with an open lower end. The upper end of the connecting compartment has a first connecting part adapted to the housing body. The housing body is coaxially disposed at the upper end of the connecting compartment, and its lower end is connected and fixed to the first connecting part. The lower end of the impact rod has a cylindrical accommodating cavity. The upper end of the detection base has a second connecting part adapted to the accommodating cavity. The impact rod is vertically installed in the housing body. The second connecting part passes through the connecting compartment and extends into the accommodating cavity, and is connected and fixed to the inner wall of the accommodating cavity. The driving assembly is fixedly connected to the impact rod and drives the impact rod to move the detection base up and down until the triboelectric power generation unit approaches or moves away from the first triboelectric sponge and the second triboelectric sponge.

[0010] Furthermore, the housing body includes a fixed outer shell and a movable outer shell. The fixed outer shell is a cylindrical structure with a first limiting circular plate coaxially arranged inside. The movable outer shell is a hollow cylindrical structure with one end open. The movable outer shell is coaxially arranged at the upper end of the fixed outer shell, and its lower end extends into the interior of the fixed outer shell and is slidably connected to the inner wall of the fixed outer shell. A second limiting circular plate is coaxially arranged inside the movable outer shell. The impact rod is arranged inside the fixed outer shell, and its upper end passes through the first limiting circular plate and the second limiting circular plate in sequence to extend into the movable outer shell. The lower part of the impact rod is coaxially arranged with a first limiting circular plate. The three limiting circular plates, the driving assembly includes a first return spring, a second return spring and a third return spring arranged sequentially along the axial direction of the impact rod, wherein the first return spring is located above the first limiting circular plate, the second return spring is located above the second limiting circular plate, and the third return spring is located between the second limiting circular plate and the third limiting circular plate. The fixed housing is provided with a third notch, and the lower part of the impact rod is provided with a driving long arm. One end of the driving long arm is flexibly connected to the impact rod, and the other end extends to abut against the inner wall of the fixed housing. A release button is provided at the third notch.

[0011] Furthermore, the housing body also includes a fixing sleeve, which is a cylindrical structure and is coaxially installed inside the fixed outer shell and located below the first limiting circular plate. The lower end of the fixing sleeve extends outside the fixed outer shell and is connected and fixed to the first connecting part. The impact rod is disposed inside the fixing sleeve. The fixing sleeve is provided with a first notch and a second notch, and its inner wall is provided with a U-shaped groove arranged along its axial direction. The first notch and the third notch are connected. The lower part of the impact rod is provided with a driving long arm and a driving short arm that are evenly spaced along its circumference. One end of the driving short arm is fixedly connected to the impact rod, and its other end extends into the U-shaped groove. A release button is provided at the third notch.

[0012] Furthermore, the lower outer side of the impact rod is provided with multiple sets of limiting components evenly spaced along its axial direction. Each set of limiting components includes two strip-shaped protrusions spaced apart circumferentially along the impact rod. The length direction of the strip-shaped protrusions is arranged along the axial direction of the impact rod. The fixing sleeve is provided with strip-shaped locking strips corresponding to the limiting components. The strip-shaped locking strips extend into the two strip-shaped protrusions of the corresponding limiting components and are slidably connected with the two strip-shaped protrusions.

[0013] Furthermore, the second connecting part is coaxially provided with a cavity, which communicates with the through hole on the detection base. The bottom of the detection base is provided with protrusions corresponding to the first triboelectric sponge and the second triboelectric sponge. The two protrusions are respectively located above the corresponding first triboelectric sponge and the second triboelectric sponge, and their shapes are adapted to the first triboelectric sponge and the second triboelectric sponge. Each protrusion is provided with the triboelectric power generation unit.

[0014] Furthermore, the first triboelectric sponge is prepared by mixing polydimethylsiloxane prepolymer, citric acid monohydrate and curing agent in a mass ratio of 10:40:1 to obtain a polydimethylsiloxane citric acid mixture, and then subjecting it to heating, curing, demolding, impregnation and drying treatments in sequence.

[0015] The second triboelectric sponge was prepared by treating the first triboelectric sponge with O2 plasma, immersing the treated sample in a citric acid buffer solution with pH=3 and bromophenol blue concentration of 0.75 g / L for a period of time, and then performing vacuuming and drying treatments in sequence.

[0016] Furthermore, the triboelectric power generation unit is made of polytetrafluoroethylene material, and the wire is installed between the detection base and the triboelectric power generation unit.

[0017] The above-mentioned triboelectric nanogenerator is used in the field of detecting urinary protein content.

[0018] The beneficial effects of the technical solution provided by this invention are as follows: This invention provides a portable urine protein content detection device with stable signal, simple structure, low preparation cost, and home-based self-testing of urine protein. This device can determine urine protein concentration from two dimensions: first, naked-eye observation, using the color change of bromophenol blue citric acid porous PDMS after protein attachment to qualitatively detect urine protein and make a rough judgment on concentration; second, detection through triboelectric nanogenerators, utilizing the principles of triboelectric generation and electrostatic induction, the bromophenol blue citric acid porous PDMS with attached protein becomes charged upon contact with PTFE material, and the charged state of the PTFE material surface is proportional to the urine protein concentration. Data is further refined by humidity sensing using blank porous PDMS, achieving the function of detecting specific disease biomarkers through the electrical signal intensity of dual detection channels. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the triboelectric nanogenerator described in this invention;

[0020] Figure 2 This is a cross-sectional view of the triboelectric nanogenerator described in this invention;

[0021] Figure 3This is a schematic diagram of the impact rod described in this invention;

[0022] Figure 4 This is a cross-sectional view of the detection base described in this invention;

[0023] Figure 5 This is a schematic diagram of the structure of the fixed shell described in this invention;

[0024] Figure 6 This is a schematic diagram of the reagent compartment described in this invention;

[0025] Figure 7 ab represents the voltage output signal diagram and humidity-voltage relationship diagram of the first triboelectric sponge and triboelectric power generation unit in the triboelectric nano-power generation device of the present invention under humidity conditions of 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, and 80%, respectively.

[0026] Figure 8 ab represents the voltage output signal diagram and humidity-voltage relationship diagram of the second triboelectric sponge and the triboelectric power generation unit in the triboelectric nano-power generation device of the present invention under humidity conditions of 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, and 80%, respectively.

[0027] Figure 9 af correspond to the voltage output signals of the triboelectric nanogenerator in this invention under 50% humidity conditions, testing artificial urine containing different concentrations of albumin at pH values ​​of 4.5, 5, 5.5, 6, 6.5, and 7.

[0028] Figure 10 ab correspond to the urine protein response voltage output signal diagram and humidity response voltage output signal diagram of the triboelectric nanogenerator in this invention when testing artificial urine containing different concentrations of albumin at pH=6 under humidity conditions of 50%, 60%, and 80%.

[0029] Figure 11 This is a schematic diagram showing the false positive results of urine protein test strips and bromophenol blue citrate porous PDMS in detecting artificial urine with ammonia concentrations of 0 mol / L, 0.1 mol / L, 0.2 mol / L, and 0.3 mol / L.

[0030] Figure 12 This is a voltage output signal diagram of the triboelectric nanogenerator in this invention detecting artificial urine with ammonia concentrations of 0 mol / L, 0.1 mol / L, 0.2 mol / L, and 0.3 mol / L. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0032] like Figure 1-6 As shown, a triboelectric nanogenerator includes a detection base 10, a connection chamber 20, a reagent chamber 30, and a drive unit. The reagent chamber 30 is hollow inside and open at the top, and contains a first triboelectric sponge 40 and a second triboelectric sponge 41. The first triboelectric sponge 40 is made of polydimethylsiloxane (PDMS), and the second triboelectric sponge 41 is made of PDMS material impregnated with bromophenol blue and citric acid. The connection chamber 20 is detachably installed at the upper end of the reagent chamber 30, and the drive unit is detachably installed at the upper end of the connection chamber 20. The detection base 10 is vertically disposed inside the connection chamber 20, with its upper end extending out of the connection chamber 20 and connected to the drive unit. Its lower end is provided with a triboelectric unit 14. The drive unit drives the detection base 10 to move up and down until the triboelectric unit 14 approaches or moves away from the first triboelectric sponge 40 and the second triboelectric sponge 41. The triboelectric unit 14 is externally connected to a wire 15.

[0033] In this invention, the first triboelectric sponge 40 is used for humidity sensing to detect the ambient humidity of the day. The electrical signal generated by the friction between the first triboelectric sponge 40 and the triboelectric power generation unit 14 is used to detect the humidity of the test day. The second triboelectric sponge 41 is used for biochemical sensing to detect proteins. By using a standard curve for detecting urinary protein under different humidity conditions, the concentration of urinary protein can be accurately detected. The second triboelectric sponge 41 is immersed in urine containing protein. The anions generated by the bromophenol blue chromogenic agent under acidic conditions combine with the cationic proteins to form a complex, causing further ionization of the chromogenic agent. When the color exceeds the buffer range of the indicator, the indicator changes color, and the color deepens with the increase of protein concentration, thereby achieving qualitative and semi-quantitative detection of urinary protein. The second triboelectric sponge 41 of this invention retains the colorimetric reaction of commercially available protein test strips. It can determine the concentration of urinary protein by the color change after immersing urine in bromophenol blue citric acid porous PDMS, or it can be used to quantitatively detect the urinary protein content by drying the sample and then detecting it with a triboelectric nanogenerator. A stable mechanical energy input is provided to the detection base 10 through the driving unit, enabling the detection base 10 to maintain a stable output and drive the triboelectric generator unit 14 to rub against two triboelectric sponges in a vertical contact manner. The electrostatic energy generated by the triboelectricity is then discharged for detection. The detection of specific disease markers in body fluids is achieved based on the change in the surface charge state after the triboelectric material comes into contact with the specific disease marker. This invention provides a portable urine protein content detection device with stable signal, simple structure, low manufacturing cost, and home self-testing. This device can determine the urine protein concentration from two dimensions: first, naked-eye observation, using the color change of bromophenol blue citric acid porous PDMS after protein attachment to perform qualitative detection and rough judgment of urine protein concentration; second, detection through triboelectric nanogenerator, utilizing the principles of triboelectric generation and electrostatic induction, the bromophenol blue citric acid porous PDMS after protein attachment to PTFE is charged, and the charge state of the PTFE surface is proportional to the urine protein concentration. The data is supplemented by humidity sensing of blank porous PDMS, realizing the function of detecting specific disease markers through the electrical signal intensity of dual detection channels.

[0034] In the above embodiment, the triboelectric power generation unit 14 is made of polytetrafluoroethylene (PTFE) material, and the wire 15 is installed between the detection base 10 and the triboelectric power generation unit 14.

[0035] In this invention, a copper foil is provided between the detection base 10 and the triboelectric unit 14. Because the PDMS and PTFE materials are located close to each other in the triboelectric sequence, the amount of charge transferred after friction is relatively small, resulting in a weak electrical signal. Protein, as a good positive electrode triboelectric material, significantly enhances the overall electron-losing ability of the second triboelectric sponge 41 after adsorption, increasing the amount of charge transferred after friction and strengthening the electrical signal generated by the external circuit. This increase in electrical signal is positively correlated with the urinary protein content. Consequently, the output signal of the triboelectric nanogenerator and the color of the second triboelectric sponge 41 both exhibit a regular enhancement, enabling the quantitative detection of proteins in urine.

[0036] In the above embodiment, the reagent compartment 30 includes a material placement section 31 and a handheld section 32. The material placement section 31 has a rectangular structure, is hollow inside and open at the top. A partition 33 is vertically provided in the middle of the material placement section 31. The first triboelectric sponge 40 and the second triboelectric sponge 41 are respectively disposed on both sides of the partition 33. The handheld section 32 is fixed to one side of the material placement section 31. The connecting compartment 20 is slidably connected to the material placement section 31.

[0037] In this invention, both the first triboelectric sponge 40 and the second triboelectric sponge 41 are rectangular structures. The partition 33 prevents mutual interference between the first triboelectric sponge 40 and the second triboelectric sponge 41 during operation. As an embodiment of this invention, the storage compartment 31 has a groove length of 20mm, a width of 14mm, and a depth of 6mm. The partition 33 divides the internal space of the storage compartment 31 into two symmetrical storage areas, with the first triboelectric sponge 40 and the second triboelectric sponge 41 respectively positioned on both sides of the partition 33. The dimensions of both the first triboelectric sponge 40 and the second triboelectric sponge 41 are 9mm long, 9mm wide, and 2mm high. The partition 33 has a length of 7mm, a width of 1mm, and a height of 1.5mm. The reagent compartment 30 of this invention has advantages such as simple structure and strong practicality.

[0038] In the above embodiment, the connecting chamber 20 is a rectangular structure adapted to the material placement part 31, with an open lower end and a through hole at the upper end. The connecting chamber 20 covers the material placement part 31 and is slidably connected to the outer wall of the corresponding side of the material placement part 31.

[0039] In this invention, the through hole allows the upper end of the detection base 10 to connect to the driving end of the driving unit. The sliding connection between the connecting chamber 20 and the material placement part 31 facilitates the assembly and disassembly of the connecting chamber 20 and the material placement part 31, and also has the advantages of low implementation cost.

[0040] In the above embodiment, the driving unit includes a housing body, an impact rod 50, and a driving assembly. The housing body is a cylindrical structure with an open lower end. The upper end of the connecting chamber 20 is provided with a first connecting portion 21 adapted to the housing body. The housing body is coaxially disposed at the upper end of the connecting chamber 20, and its lower end is connected and fixed to the first connecting portion 21. The lower end of the impact rod 50 is provided with a cylindrical accommodating cavity 51. The upper end of the detection base 10 is provided with a second connecting portion 11 adapted to the accommodating cavity 51. The impact rod 50 is vertically installed in the housing body. The second connecting portion 11 passes through the connecting chamber 20 and extends into the accommodating cavity 51, and is connected and fixed to the inner wall of the accommodating cavity 51. The driving assembly is fixedly connected to the impact rod 50 and drives the impact rod 50 to move the detection base 10 up and down until the triboelectric power generation unit 14 approaches or moves away from the first triboelectric sponge 40 and the second triboelectric sponge 41. The through hole on the connecting chamber 20 passes through the first connecting portion 21.

[0041] In this invention, the housing body serves to fix and protect the impact rod 50.

[0042] In the above embodiment, the housing body includes a fixed outer shell 60, a movable outer shell 61, and a fixed sleeve 62. The fixed outer shell 60 is a cylindrical structure with a first limiting circular plate 601 coaxially arranged inside. The movable outer shell 61 is a hollow cylindrical structure with one end open. The movable outer shell 61 is coaxially arranged at the upper end of the fixed outer shell 60, and its lower end extends into the interior of the fixed outer shell 60 and is slidably connected to the inner wall of the fixed outer shell 60. A second limiting circular plate 611 is coaxially arranged inside the movable outer shell 61. The fixing sleeve 62 is a cylindrical structure, coaxially mounted inside the fixing housing 60 and located below the first limiting circular plate 601. The lower end of the fixing sleeve 62 extends outside the fixing housing 60 and is connected and fixed to the first connecting part 21. The impact rod 50 is disposed inside the fixing sleeve 62, and its upper end passes through the first limiting circular plate 601 and the second limiting circular plate 611 in sequence and extends into the moving housing 61. The lower part of the impact rod 50 is coaxially provided with a third limiting circular plate 52. The driving assembly includes components along the... A first return spring 53, a second return spring 54, and a third return spring 55 are sequentially arranged axially on the impact rod 50. The first return spring 53 is located above the first limiting circular plate 601, the second return spring 54 is located above the second limiting circular plate 611, and the third return spring 55 is located between the second limiting circular plate 611 and the third limiting circular plate 52. The fixing sleeve 62 has a first notch 621 and a second notch 622, and its inner wall has a U-shaped groove 623 arranged axially. The fixed housing 60 is provided with a third notch, and the first notch 621 and the third notch are connected. The lower part of the impact rod 50 is provided with a driving long arm 56 and a driving short arm 57 evenly spaced along its circumference. One end of the driving long arm 56 is flexibly connected to the impact rod 50, and the other end extends to abut against the inner wall of the fixed sleeve 62. One end of the driving short arm 57 is fixedly connected to the impact rod 50, and the other end extends into the U-shaped groove 623. A release button 603 is provided at the third notch.

[0043] In this invention, the first connecting part 21 of the connecting chamber 20 is fixed to the fixing sleeve 62 by a snap fastener. The snap fastener structure has the advantages of convenient assembly and disassembly and low implementation cost. The top of the impact rod 50 has a cross-shaped structure. The first limiting circular plate 601 and the second limiting circular plate 611 are both provided with cross-shaped through holes that match the top of the impact rod 50. The first limiting circular plate 601 and the second limiting circular plate 611 fix the impact rod 50, which not only ensures the fixing effect of the impact rod 50, but also ensures the straightness of the movement trajectory of the impact rod 50, thereby achieving stable driving and accurate driving direction of the detection base 10. Optimally, the upper end of the fixing sleeve 62 abuts against the second limiting circular plate 611, and its lower end extends into the connecting chamber 20. The second notch 622 is used to extend the wire 15. When the impact rod 50 is in the initial position, the drive arm 56 is located below the first notch 621, and one end of the drive arm 57 abuts against the bottom wall of the U-shaped groove 623. The first return spring 53, the second return spring 54, and the third return spring 55 are all in a relaxed state. When the test begins, an external force pulls the moving housing 61 upward until the drive arm 56 moves to the first notch 621 and extends out of the first notch 621 and the third notch to abut against the release button 603. At this time, under the action of the first limiting plate 601, the second limiting plate 611, and the third limiting plate 52, the first return spring 53 and the third return spring 55 are compressed. Then, press the release button 603 to drive the long arm 56 back into the fixed sleeve 62. At this time, under the action of the third return spring 55, the drive impact rod 50 drives the detection base 10 to move downward until the detection base 10 simultaneously contacts and rubs with the first triboelectric sponge 40 and the second triboelectric sponge 41. Repeat the above operation in sequence, and the device generates an electrical signal, which can realize the detection of urinary protein content in the sample.

[0044] In the above embodiment, the lower outer side of the impact rod 50 is provided with multiple sets of limiting components evenly spaced along its axial direction. Each set of limiting components includes two strip-shaped protrusions 58 spaced apart circumferentially along the impact rod 50. The length direction of the strip-shaped protrusions 58 is arranged along the axial direction of the impact rod 50. The fixing sleeve 62 is provided with strip-shaped locking strips corresponding to the limiting components. The strip-shaped locking strips extend into the two strip-shaped protrusions 58 of the corresponding limiting components and are slidably connected with the two strip-shaped protrusions 58.

[0045] In this invention, the strip-shaped protrusion 58 and the strip-shaped retaining strip serve to limit the movement of the impact rod 50, ensuring the direction of movement of the impact rod 50, preventing rotation or displacement when the impact rod 50 falls downwards, and effectively preventing the impact rod 50 from falling off. Ideally, two limiting components and two strip-shaped retaining strips are provided; however, in practical applications, the number of limiting components and strip-shaped retaining strips can be increased as needed.

[0046] In the above embodiment, a cavity 12 is coaxially provided in the second connecting part 11. The cavity communicates with the through hole on the detection base 10. The bottom of the detection base 10 is provided with protrusions 13 corresponding to the first triboelectric sponge 40 and the second triboelectric sponge 41. The two protrusions 13 are respectively located above the corresponding first triboelectric sponge 40 and the second triboelectric sponge 41. Their shapes are adapted to the first triboelectric sponge 40 and the second triboelectric sponge 41. Each protrusion 13 is provided with the triboelectric power generation unit 14.

[0047] In this invention, the protrusion 13 is a rectangular structure adapted to the shapes of the first triboelectric sponge 40 and the second triboelectric sponge 41, allowing the triboelectric power generation unit 14 to fully contact the first triboelectric sponge 40 and the second triboelectric sponge 41, ensuring both friction and power generation effects. In one embodiment of this invention, the protrusion 13 has a length and width of 7mm and a height of 3mm. The cavity 12 serves to house the wire 15, which extends through the cavity 12 and the second notch 622 into the external device. Ideally, the diameter of the cavity 12 is 1mm.

[0048] In this invention, the detection base 10, connection chamber 20, reagent chamber 30, fixed outer shell 60, movable outer shell 61 and fixed sleeve 62 are all made of resin material to reduce the weight of the device and the implementation cost.

[0049] Furthermore, the present invention also relates to a method for preparing a triboelectric nanogenerator, comprising the following steps:

[0050] S1. Prepare the detection base 10, the connecting chamber 20, the reagent chamber 30, the fixed shell 60, the movable shell 61, and the fixing sleeve 62. The detection base 10, the connecting chamber 20, and the reagent chamber 30 are made of resin material using 3D printing technology. The present invention does not limit the materials used to prepare the fixed shell 60, the movable shell 61, and the fixing sleeve 62.

[0051] S2. Stick copper foil tape to the bottom of the two protrusions 13 of the test base 10. Cut PTFE material of appropriate size according to the size of the protrusions 13. Stick the wire 15 and PTFE material to the copper foil tape to complete the installation of the triboelectric power generation unit 14.

[0052] S3. Preparation of the first triboelectric sponge 40: PDMS prepolymer, citric acid monohydrate and curing agent are mixed evenly at a mass ratio of 10:40:1 to obtain a PDMS-citric acid mixture. The mixture is then poured into a mold and placed in an oven at 60°C for 12 hours to cure the PDMS-citric acid mixture. The cured mold is then removed and demolded. The resulting product is then soaked in deionized water for more than 6 hours until all the citric acid is dissolved. After drying, a porous PDMS with a length of 2cm, a width of 2cm and a height of 2mm is obtained. After cutting to size, the first triboelectric sponge 40 has a length of 9mm, a width of 9mm and a height of 2mm.

[0053] S4. Preparation of the second triboelectric sponge 41: PDMS prepolymer, citric acid monohydrate, and curing agent are mixed evenly at a mass ratio of 10:40:1 to obtain a PDMS-citric acid mixture. A mold is formed, and the filled mold is placed in an oven at 60℃ and heated for 12 hours to cure the PDMS-citric acid mixture. The cured mold is removed, demolded, and the resulting product is soaked in deionized water for at least 6 hours until all the citric acid is dissolved. After soaking, it is dried to obtain porous PDMS with a length of 2cm, a width of 2cm, and a height of 2mm. The obtained porous PDMS was treated with O2 plasma at the high setting for 5 minutes on both sides. The treated sample was then immersed in a citric acid buffer solution with a pH of 3 and a bromophenol blue concentration of 0.75 g / L. The air in the porous PDMS was expelled, and the solution and PDMS were then placed in an oil-free vacuum pump and evacuated for 30 minutes. After removal, the sample was placed in a petri dish and dried in a 60°C oven. After being cut to size, a second triboelectric sponge 41 with a length of 9 mm, a width of 9 mm, and a height of 2 mm was obtained.

[0054] S5. Place the first triboelectric sponge 40 and the second triboelectric sponge 41 into the material placement section, and assemble the impact rod 50, the first return spring 53, the second return spring 54, the third return spring 55, the fixed outer shell 60, the movable outer shell, the fixed sleeve 62, the detection base 10, the connecting chamber 20 and the reagent chamber 30 in sequence. Extend the wire 15 out of the fixed outer shell 60 to obtain the triboelectric nanogenerator.

[0055] To test the output performance of blank porous PDMS and bromophenol blue citric acid porous PDMS under different humidity levels, humidity gradients of 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, and 80% were set. An electromagnetic vibrator controlled the impact rod 50 to rub the first triboelectric sponge 40 and the second triboelectric sponge 41 against PTFE material, respectively, at a frequency of 5Hz and a force of 7N. The output voltage was displayed on an oscilloscope. Figure 6 and Figure 7It can be seen that the electrical signals generated by the friction between the first triboelectric sponge 40 and the second triboelectric sponge 41 and PTFE are significantly affected by humidity, exhibiting a strong negative correlation. Therefore, the environmental humidity during testing can be effectively determined by the electrical signal generated by the friction between the porous PDMS material in the blank sample cell and PTFE, which can further refine the test data for urinary protein.

[0056] The main principle behind the adsorption of proteins by bromophenol blue is that at around pH 3, bromophenol blue generates negatively charged ions, while at lower pH levels, proteins are positively charged. Bromophenol blue and proteins can then adsorb each other via electrostatic induction. Therefore, solution pH has a certain influence on protein adsorption. To further investigate the detection performance of a triboelectric nanogenerator under artificial urine conditions at different pH levels, artificial urine containing different concentrations of albumin was prepared with pH values ​​of 4.5, 5, 5.5, 6, 6.5, and 7. These urine samples with different pH values ​​were then detected using a triboelectric nanogenerator. Figure 8 As can be seen, when the pH of the artificial urine is <6.5, the electrical signal displayed by the oscilloscope shows a good correlation with the urine protein concentration. When the pH of the artificial urine is 7, the electrical signal displayed by the oscilloscope does not increase significantly with the increase of urine protein concentration. The main reason is that when the pH of the artificial urine is high, the local acidity of the second triboelectric sponge 41 when it is soaked in the urine is difficult to maintain, and the electrostatic adsorption of protein and bromophenol blue is insufficient, resulting in abnormal urine protein detection. However, it is still possible to clearly detect whether there is protein in the urine.

[0057] To further explore the practicality of the triboelectric nanogenerator for detecting urinary protein content under different humidity conditions, the urinary protein content in artificial urine containing different concentrations of albumin at pH 6 was measured under three humidity conditions: 50%, 60%, and 80%. Figure 9 The results show that the second triboelectric sponge 41 exhibits a good colorimetric reaction for protein detection, allowing for a rough assessment of protein concentration levels through color. Furthermore, the triboelectric nanogenerator can effectively distinguish the detection signals of proteins at different concentrations. Simultaneously, the detection signal from a blank porous PDMS can effectively differentiate between different humidity conditions, further refining the protein detection data.

[0058] Bromophenol blue is an indicator for the specific adsorption and detection of urinary protein, and it is also a good pH indicator, showing a good response to pH values. Therefore, when the urine pH is high, conventional urine protein test strips and bromophenol blue-citric acid porous PDMS are unable to maintain a local acidic condition, leading to false positives. To further investigate whether a urine protein detection device can solve the false positive problem, solutions with ammonia concentrations of 0 mol / L, 0.1 mol / L, 0.2 mol / L, and 0.3 mol / L were prepared using artificial urine at pH=6. These solutions were then soaked and adsorbed using bromophenol blue-citric acid porous PDMS before detection. Figure 10-11 As shown, although both the protein test paper and the bromophenol blue citric acid porous PDMS showed false positives in terms of color development, the output performance results displayed by the oscilloscope indicated that the triboelectric nanogenerator could accurately detect whether the triboelectric material contained protein.

[0059] Similarly, triboelectric nanogenerators for urine protein detection can be used to attach other disease biomarkers to the surface of porous PDMS by adjusting the specific adsorbents attached to the PDMS. The detection of other substances in body fluids can be achieved by detecting the surface charge after friction with PTFE.

[0060] In this document, the directional terms such as front, back, top, and bottom are defined according to the positions of components in the accompanying drawings and between components, solely for the purpose of clarity and convenience in expressing the technical solution. It should be understood that the use of these directional terms should not limit the scope of protection claimed in this application.

[0061] Where there is no conflict, the above embodiments and features described herein can be combined with each other.

[0062] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A triboelectric nanogenerator, characterized in that, The device includes a detection base, a connecting chamber, a reagent chamber, and a drive unit. The reagent chamber is hollow inside and open at the top. It contains a first triboelectric sponge and a second triboelectric sponge. The first triboelectric sponge is made of polydimethylsiloxane material, and the second triboelectric sponge is made of polydimethylsiloxane material that has been impregnated with bromophenol blue and citric acid. The connecting chamber is detachably installed at the top of the reagent chamber, and the drive unit is detachably installed at the top of the connecting chamber. The detection base is vertically installed inside the connecting chamber, with its upper end extending out of the connecting chamber and connected to the drive unit. Its lower end is equipped with a triboelectric power generation unit. The drive unit drives the detection base to move up and down until the triboelectric power generation unit is close to or away from the first and second triboelectric sponges. The triboelectric power generation unit is connected to an external wire.

2. The triboelectric nanogenerator according to claim 1, characterized in that, The reagent compartment includes a material placement section and a handheld section. The material placement section has a rectangular structure, is hollow inside and open at the top. A partition is vertically provided in the middle of the material placement section. The first triboelectric sponge and the second triboelectric sponge are respectively disposed on both sides of the partition. The handheld section is fixed to one side of the material placement section. The connecting compartment is slidably connected to the material placement section.

3. The triboelectric nanogenerator according to claim 1, characterized in that, The driving unit includes a housing body, an impact rod, and a driving assembly. The housing body is a cylindrical structure with an open lower end. The upper end of the connecting compartment has a first connecting part adapted to the housing body. The housing body is coaxially disposed at the upper end of the connecting compartment, and its lower end is connected and fixed to the first connecting part. The lower end of the impact rod has a cylindrical accommodating cavity. The upper end of the detection base has a second connecting part adapted to the accommodating cavity. The impact rod is vertically installed in the housing body. The second connecting part passes through the connecting compartment and extends into the accommodating cavity, and is connected and fixed to the inner wall of the accommodating cavity. The driving assembly is fixedly connected to the impact rod and drives the impact rod to move the detection base up and down until the triboelectric power generation unit approaches or moves away from the first triboelectric sponge and the second triboelectric sponge.

4. The triboelectric nanogenerator according to claim 3, characterized in that, The housing body includes a fixed outer shell and a movable outer shell. The fixed outer shell is a cylindrical structure with a first limiting circular plate coaxially arranged inside. The movable outer shell is a hollow cylindrical structure with one end open. The movable outer shell is coaxially arranged at the upper end of the fixed outer shell, and its lower end extends into the interior of the fixed outer shell and is slidably connected to the inner wall of the fixed outer shell. A second limiting circular plate is coaxially arranged inside the movable outer shell. The impact rod is arranged inside the fixed outer shell, and its upper end passes through the first limiting circular plate and the second limiting circular plate in sequence to extend into the movable outer shell. A third limiting plate is coaxially arranged at the lower part of the impact rod. The circular plate, the driving assembly includes a first return spring, a second return spring and a third return spring arranged sequentially along the axial direction of the impact rod, wherein the first return spring is located above the first limiting circular plate, the second return spring is located above the second limiting circular plate, and the third return spring is located between the second limiting circular plate and the third limiting circular plate. The fixed housing is provided with a third notch, and the lower part of the impact rod is provided with a driving long arm. One end of the driving long arm is flexibly connected to the impact rod, and the other end extends to abut against the inner wall of the fixed housing. A release button is provided at the third notch.

5. A triboelectric nanogenerator according to claim 4, characterized in that, The housing body also includes a fixing sleeve, which is a cylindrical structure and is coaxially installed inside the fixed housing and located below the first limiting circular plate. The lower end of the fixing sleeve extends outside the fixed housing and is connected and fixed to the first connecting part. The impact rod is disposed inside the fixing sleeve. The fixing sleeve has a first notch and a second notch, and its inner wall has a U-shaped groove arranged along its axial direction. The first notch and the third notch are connected. The lower part of the impact rod has a driving long arm and a driving short arm that are evenly spaced along its circumference. One end of the driving short arm is fixedly connected to the impact rod, and the other end extends into the U-shaped groove. A release button is provided at the third notch.

6. The triboelectric nanogenerator according to claim 4, characterized in that, The lower outer side of the impact rod is provided with multiple sets of limiting components evenly spaced along its axial direction. Each set of limiting components includes two strip-shaped protrusions spaced apart circumferentially along the impact rod. The length direction of the strip-shaped protrusions is arranged along the axial direction of the impact rod. The fixing sleeve is provided with strip-shaped locking strips corresponding to the limiting components. The strip-shaped locking strips extend into the two strip-shaped protrusions of the corresponding limiting components and are slidably connected with the two strip-shaped protrusions.

7. A triboelectric nanogenerator according to claim 3, characterized in that, The second connecting part has a cavity coaxially arranged inside, which communicates with the through hole on the detection base. The bottom of the detection base has protrusions corresponding to the first triboelectric sponge and the second triboelectric sponge. The two protrusions are respectively located above the corresponding first triboelectric sponge and the second triboelectric sponge, and their shapes are adapted to the first triboelectric sponge and the second triboelectric sponge. Each protrusion is provided with the triboelectric power generation unit.

8. The triboelectric nanogenerator according to claim 1, characterized in that, The first triboelectric sponge is prepared by mixing polydimethylsiloxane prepolymer, citric acid monohydrate and curing agent in a mass ratio of 10:40:1 to obtain a polydimethylsiloxane-citric acid mixture, and then subjecting it to heating, curing, demolding, impregnation and drying processes in sequence. The second triboelectric sponge was prepared by treating the first triboelectric sponge with O2 plasma, immersing the treated sample in a citric acid buffer solution with pH=3 and bromophenol blue concentration of 0.75 g / L for a period of time, and then performing vacuuming and drying treatments in sequence.

9. A triboelectric nanogenerator according to claim 7, characterized in that, The triboelectric generator unit is made of polytetrafluoroethylene, and the wire is installed between the detection base and the triboelectric generator unit.

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