Body sensor manufacturing method

Abstract

A method for manufacturing a bulk sensor relates to the field of photoelectrochemical biotechnology detection technology. The method comprises: screen-printing a TiO2@Au slurry onto a conductive substrate, maintaining the substrate at a first temperature for a first time, to obtain a TiO2@Au electrode, wherein the concentration of TiO2@Au powder in the TiO2@Au slurry is 40% to 81.9%; dripping or spin-coating a g-C3N4 dispersion onto the surface of the TiO2@Au electrode, maintaining the substrate at a second temperature for a second time, to obtain a TiO2@Au / g-C3N4 photoanode; dripping an aptamer probe solution onto the surface of the TiO2@Au / g-C3N4 photoanode, incubating the solution at a third temperature for a third time, wherein the aptamer probe comprises a DNA aptamer probe for serotonin and / or a DNA aptamer probe for dopamine; and rinsing the surface of the TiO2@Au / g-C3N4 photoanode to obtain the bulk sensor. The body sensor manufacturing method provided in the present disclosure can prepare a photoelectrochemical bioaptamer sensor based on TiO2@Au / g-C3N4 nanocomposite material to quickly and sensitively detect depression-related biomarkers, which is conducive to meeting the needs of early detection and large-scale examinations.

Description

Technical Field

[0001] The present disclosure relates to the field of photoelectrochemical biotechnology detection technology, and in particular to a method for manufacturing a body sensor. Background Art

[0002] Depression is a mental disorder that severely impacts the physical and mental health of people worldwide. Its increasing prevalence has created immense pressure and challenges for society and families. Therefore, rapid detection and early diagnosis of depression are crucial.

[0003] Currently, traditional methods for detecting depression have significant limitations. Clinical symptom assessment relies on specialized physicians, which is highly subjective, can easily lead to overlooking early symptoms, and lacks objective quantitative indicators. Biomarker assays (serotonin and dopamine) such as fluorometry, thin-layer chromatography, gas chromatography, gas chromatography-mass spectrometry, and high-performance liquid chromatography are complex, require specialized personnel and equipment, are time-consuming, costly, and lack sensitivity. These factors hinder the ability to meet the needs of early detection and large-scale screening. Summary of the Invention

[0004] The present disclosure provides a method for manufacturing a body sensor, which can prepare a photoelectrochemical bioaptamer sensor based on TiO2@Au / g-C3N4 nanocomposite material to quickly and sensitively detect depression-related biomarkers, which is conducive to meeting the needs of early detection and large-scale inspection.

[0005] The present disclosure provides a method for manufacturing a body sensor, comprising:

[0006] The TiO2@Au slurry is screen-printed on a conductive substrate and kept at a first temperature for a first time to obtain a TiO2@Au electrode, wherein the concentration of the TiO2@Au powder in the TiO2@Au slurry is 40% to 81.9%;

[0007] Dropping or spin-coating a g-C3N4 dispersion on the surface of the TiO2@Au electrode, and maintaining the temperature at a second temperature for a second time to obtain a TiO2@Au / g-C3N4 photoanode;

[0008] adding an aptamer probe solution dropwise onto the surface of the TiO2@Au / g-C3N4 photoanode and incubating the solution at a third temperature for a third time, wherein the aptamer probe comprises a DNA aptamer probe for serotonin and / or a DNA aptamer probe for dopamine;

[0009] The TiO2@Au / g-C3N4 photoanode surface was rinsed to obtain the bulk sensor.

[0010] In an exemplary embodiment of the present disclosure, the body sensor manufacturing method further includes preparing TiO2@Au slurry; preparing the TiO2@Au slurry includes:

[0011] 40~81.9% TiO2@Au powder, 0.1~2% ethyl cellulose, 3~8% binder, 15~35% solvent, 0~6% accelerator, 0~2% surface additive, 0~4% dispersant, and 0~1% defoamer are mixed evenly to form a TiO2@Au slurry.

[0012] In an exemplary embodiment of the present disclosure, preparing TiO2@Au slurry further includes preparing TiO2@Au powder; preparing TiO2@Au powder includes:

[0013] Add reducing agent to the boiling water and continue to boil;

[0014] Disperse titanium dioxide powder in the solution and continue boiling for 10-30 minutes;

[0015] Add 1% chloroauric acid aqueous solution and continue boiling for 10-30 minutes to obtain the first reaction solution;

[0016] The first reaction solution was transferred to a hydrothermal reactor and reacted at a fourth temperature for a fourth time to obtain TiO2@Au powder.

[0017] In an exemplary embodiment of the present disclosure, the titanium dioxide powder includes one or more of nano titanium dioxide powder, submicron titanium dioxide powder and micron titanium dioxide powder.

[0018] In an exemplary embodiment of the present disclosure, a 1% aqueous solution of chloroauric acid is added, wherein the mass of the added chloroauric acid is 0.1% to 5% of the titanium dioxide powder.

[0019] In an exemplary embodiment of the present disclosure, a reducing agent is added to the boiling water and the boiling is continued, wherein the reducing agent includes one or more of sodium citrate and tannic acid, and the concentration of the reducing agent is 0.5% to 2.5%.

[0020] In an exemplary embodiment of the present disclosure, the body sensor manufacturing method further includes preparing a g-C3N4 dispersion; the preparing the g-C3N4 dispersion includes:

[0021] A 1.5 mol / L urea aqueous solution was prepared, melamine was added, and stirring was continued for 30 minutes to obtain a second reaction solution;

[0022] The second reaction solution is transferred to a hydrothermal reactor and reacted at a fifth temperature for a fifth time to obtain a g-C3N4 precursor;

[0023] keeping the g-C3N4 precursor in a muffle furnace at a sixth temperature for a sixth time to obtain g-C3N4 powder;

[0024] The g-C3N4 powder was ultrasonically dispersed in water for 10 to 60 minutes, and the supernatant obtained after centrifugation was the g-C3N4 dispersion.

[0025] In an exemplary embodiment of the present disclosure, when a 1.5 mol / L urea aqueous solution is prepared and melamine is added, the molar mass ratio of melamine to urea is 1:2 to 1:5.

[0026] In an exemplary embodiment of the present disclosure, the first temperature is 250°C~500°C, and the first time is 20~120 minutes; the second temperature is 100°C~500°C, and the second time is 0.5~3 hours; the third temperature is 37°C, and the third time is 10~120 minutes; the fourth temperature is 120~180°C, and the fourth time is 0.5~24 hours; the fifth temperature is 110~180°C, and the fifth time is 2~24 hours; the sixth temperature is 400~650°C, and the sixth time is 0.5~5 hours.

[0027] In an exemplary embodiment of the present disclosure, the surface of the TiO2@Au / g-C3N4 photoanode is rinsed with a liquid comprising one or more of ultrapure water, sterile water, PBS buffer, and Tris-HCl buffer.

[0028] The present disclosure provides a method for manufacturing a body sensor, which comprises preparing a TiO2@Au / g-C3N4 photoanode, i.e., the working electrode of the body sensor, through steps S100 to S200, and then incubating specific bioaptamer probes for serotonin and dopamine on the surface of the working electrode through step S300. The sensor is assembled into a nanocomposite material by assembling gold nanoparticle-coated titanium dioxide and an ultra-thin layer of graphene-phase carbon nitride two-dimensional material, and combining it with specific bioaptamers to achieve rapid and sensitive detection of depression-related biomarkers.

[0029] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The accompanying drawings are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and together with the specification, are used to explain the principles of the present disclosure. Obviously, the drawings described below are only some embodiments of the present disclosure, and those skilled in the art can derive other drawings based on these drawings without inventive effort.

[0031] Figure 1 The flowchart of an exemplary embodiment of the method for manufacturing a body sensor disclosed herein is shown.

[0032] Figure 2This is the morphology of the TiO2 powder used in Example 1 of the body sensor manufacturing method disclosed in the present invention.

[0033] Figure 3 This is a scanning electron microscope image of the TiO2@Au composite material prepared in Example 2 of the body sensor manufacturing method disclosed in the present invention.

[0034] Figure 4 This is an element mapping image of the Ti element in the TiO2@Au composite material prepared in Example 2 of the body sensor manufacturing method disclosed in the present invention.

[0035] Figure 5 This is an element mapping image of the O element in the TiO2@Au composite material prepared in Example 2 of the body sensor manufacturing method disclosed in the present invention.

[0036] Figure 6 This is an element mapping image of the Au element in the TiO2@Au composite material prepared in Example 2 of the body sensor manufacturing method disclosed in the present invention.

[0037] Figure 7 This is a scanning electron microscope image of the surface of the TiO2@Au electrode after sintering in Example 2 of the body sensor manufacturing method disclosed in the present invention.

[0038] Figure 8 This is a comparison chart of IT curves of the photoanode films of Example 3, Comparative Example 1, and Comparative Example 2 in the body sensor manufacturing method disclosed herein.

[0039] Figure 9 This is the detection result of serotonin by the body sensor provided in Example 2 of the body sensor manufacturing method disclosed in the present invention.

[0040] Figure 10 This is the detection result of dopamine by the body sensor provided in Example 3 of the body sensor manufacturing method disclosed in the present invention. DETAILED DESCRIPTION

[0041] Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete and will fully convey the concepts of the example embodiments to those skilled in the art. Like reference numerals in the figures represent identical or similar structures, and thus their detailed descriptions will be omitted. Furthermore, the figures are merely schematic illustrations of the present disclosure and are not necessarily drawn to scale.

[0042] Unless otherwise specified or explained, technical or scientific terms used in this disclosure should have the ordinary meanings understood by persons of ordinary skill in the art to which this disclosure belongs. The terms "a," "an," "the," "the," and "at least one" are used to indicate the presence of one or more elements / components / etc.; the terms "including" and "having" are used to express an open-ended inclusiveness and indicate that additional elements / components / etc. may be present in addition to the listed elements / components / etc.; the terms "first" and "second" are used only as labels and do not limit the quantity, importance, or order of their objects.

[0043] When describing the proportion of each component in the present disclosure, unless otherwise specified, it refers to the mass fraction of the component.

[0044] Traditional methods for detecting depression have significant limitations. Clinical symptom assessment relies on specialized physicians, which is highly subjective, making early symptoms easily overlooked. Furthermore, there is a lack of objective, quantitative indicators. Biomarker assays (serotonin and dopamine) such as fluorometry, thin-layer chromatography, gas chromatography, gas chromatography-mass spectrometry, and high-performance liquid chromatography are complex, require specialized personnel and equipment, are time-consuming, costly, and lack sensitivity. These factors hinder the ability to meet the needs of early detection and large-scale screening.

[0045] In view of the above problems, the present disclosure provides a method for manufacturing a body sensor, which is used to prepare a photoelectrochemical bioaptamer sensor based on TiO2@Au / g-C3N4 nanocomposite material. Figure 1 As shown, including:

[0046] Step S100: screen-printing a TiO2@Au slurry on a conductive substrate and maintaining the slurry at a first temperature for a first time to obtain a TiO2@Au electrode, wherein the concentration of the TiO2@Au powder in the TiO2@Au slurry is 40% to 81.9%;

[0047] Step S200: dripping or spin-coating a g-C3N4 dispersion on the surface of the TiO2@Au electrode, and maintaining the temperature at a second temperature for a second time to obtain a TiO2@Au / g-C3N4 photoanode;

[0048] Step S300: adding an aptamer probe solution to the surface of the TiO2@Au / g-C3N4 photoanode and incubating at a third temperature for a third time, wherein the aptamer probe includes a DNA aptamer probe for serotonin and / or a DNA aptamer probe for dopamine;

[0049] Step S400: Rinse the surface of the TiO2@Au / g-C3N4 photoanode to obtain a body sensor.

[0050] The present disclosure provides a method for manufacturing a body sensor, which comprises preparing a TiO2@Au / g-C3N4 photoanode, i.e., the working electrode of the body sensor, through steps S100 to S200, and then incubating specific bioaptamer probes for serotonin and dopamine on the surface of the working electrode through step S300. The sensor is assembled into a nanocomposite material by assembling gold nanoparticle-coated titanium dioxide and an ultra-thin layer of graphene-phase carbon nitride two-dimensional material, and combining it with specific bioaptamers to achieve rapid and sensitive detection of depression-related biomarkers.

[0051] In an exemplary embodiment of the present disclosure, the body sensor manufacturing method further includes step S110: preparing TiO2@Au slurry; specifically comprising:

[0052] 40~81.9% TiO2@Au powder, 0.1~2% ethyl cellulose, 3~8% binder, 15~35% solvent, 0~6% accelerator, 0~2% surface additive, 0~4% dispersant, and 0~1% defoamer are mixed evenly to form a TiO2@Au slurry.

[0053] The preparation of TiO2@Au slurry may further include step S111: preparing TiO2@Au powder. Specifically, the step includes:

[0054] Add reducing agent to the boiling water and continue to boil;

[0055] Disperse titanium dioxide powder in the solution and continue boiling for 10-30 minutes;

[0056] Add 1% chloroauric acid aqueous solution and continue boiling for 10-30 minutes to obtain the first reaction solution;

[0057] The first reaction solution was transferred to a hydrothermal reactor and reacted at a fourth temperature for a fourth time to obtain TiO2@Au powder.

[0058] Exemplarily, a reducing agent is added to boiling water, wherein the reducing agent may include one or more of sodium citrate and tannic acid. Preferably, the concentration of the reducing agent is 0.5% to 2.5%. Specifically, a certain amount of water is placed in a beaker and boiled. An appropriate amount of the above-mentioned reducing agent is added while rapidly stirring and the solution is boiled for 5 to 10 minutes. A certain amount of TiO2 particles is then dispersed in the solution and the solution is boiled again. The titanium dioxide powder may include one or more of nano-titanium dioxide powder, submicron titanium dioxide powder, and micron titanium dioxide powder. After boiling for 10 to 30 minutes, a 1% aqueous solution of chloroauric acid is quickly added and the solution is boiled for 10 to 30 minutes to obtain a first reaction solution. Exemplarily, when the 1% aqueous solution of chloroauric acid is added, the mass of the added chloroauric acid is 0.1% to 5% of the titanium dioxide powder.

[0059] The first reaction solution is transferred to a hydrothermal reactor and reacted at a fourth temperature for a fourth time to obtain TiO2@Au powder. For example, the hydrothermal reaction temperature (i.e., the fourth temperature) of the first reaction solution in the hydrothermal reactor is 120-180°C, and the reaction time (i.e., the fourth time) is 0.5-24 hours.

[0060] In an exemplary embodiment of the present disclosure, the body sensor manufacturing method further includes step S112: preparing a g-C3N4 dispersion, specifically comprising:

[0061] A 1.5 mol / L urea aqueous solution was prepared, melamine was added, and stirring was continued for 30 minutes to obtain a second reaction solution;

[0062] The second reaction solution is transferred to a hydrothermal reactor and reacted at a fifth temperature for a fifth time to obtain a g-C3N4 precursor;

[0063] keeping the g-C3N4 precursor in a muffle furnace at a sixth temperature for a sixth time to obtain g-C3N4 powder;

[0064] The g-C3N4 powder was ultrasonically dispersed in water for 10 to 60 minutes, and the supernatant obtained after centrifugation was the g-C3N4 dispersion.

[0065] For example, a 1.5 mol / L urea aqueous solution is prepared in a beaker and a certain amount of melamine is added, specifically, the molar mass ratio of melamine to urea is 1:2 to 1:5. After continuous stirring for 30 minutes, a second reaction solution is obtained. This second reaction solution is placed in a hydrothermal reactor and reacted at a fifth temperature for a fifth time to obtain a g-C3N4 precursor. Specifically, the hydrothermal reaction temperature (i.e., the fifth temperature) of the second reaction solution in the hydrothermal reactor is 110-180°C, and the reaction time (i.e., the fifth time) is 2-24 hours.

[0066] After obtaining the g-C3N4 precursor, the precursor is held in a muffle furnace at a sixth temperature for a sixth time. The resulting powder is then ultrasonically dispersed in water for 10 to 60 minutes. The supernatant obtained after centrifugation is the ultrathin g-C3N4 dispersion. Specifically, the g-C3N4 precursor is heat-treated in the muffle furnace at a temperature (i.e., the sixth temperature) of 400 to 650°C for a holding time (i.e., the sixth time) of 0.5 to 5 hours.

[0067] After preparing the TiO2@Au slurry, in step S100, the TiO2@Au slurry is screen-printed onto a conductive substrate and then held at a first temperature for a first time to produce a TiO2@Au electrode. Specifically, after screen-printing, the slurry is held at 250°C to 500°C for 20 to 120 minutes to produce the TiO2@Au electrode.

[0068] In step S200, a certain amount of g-C3N4 dispersion, which can be the g-C3N4 dispersion prepared by the aforementioned method, is dropwise added or spin-coated onto the surface of the TiO2@Au electrode. The electrode is then heat-treated in a muffle furnace at a second temperature for a second time to produce a TiO2@Au / g-C3N4 photoanode. Specifically, the TiO2@Au electrode, to which the g-C3N4 dispersion has been dropwise added or spin-coated, can be heat-treated in the muffle furnace at a temperature (i.e., the second temperature) of 100-500°C for a holding time (i.e., the second time) of 0.5-3 hours.

[0069] In step S300, an aptamer probe solution is added to the surface of the TiO2@Au / g-C3N4 photoanode. The aptamer probes may include DNA aptamer probes for serotonin and / or DNA aptamer probes for dopamine, thereby achieving a highly sensitive and rapid response to depression-related biomarkers. For example, the TiO2@Au / g-C3N4 photoanode with the aptamer probe solution is incubated at 37°C for 10-120 minutes to immobilize the bioaptamer on the working electrode surface.

[0070] In step S400, the surface of the TiO2@Au / g-C3N4 photoanode is rinsed to remove any unbound bioaptamers from step S300. The resulting sensor can then be stored at a temperature for future use. For example, the TiO2@Au / g-C3N4 photoanode surface can be rinsed with one or more of ultrapure water, sterile water, PBS buffer, or Tris-HCl buffer to ensure complete removal of any unbound bioaptamers.

[0071] The photoelectrochemical bioaptamer sensor based on TiO2@Au / g-C3N4 nanocomposite materials obtained by the above method can be used for rapid detection of depression. Experimental results show that the detection time can be shortened to within one minute, which greatly improves the detection efficiency and is conducive to providing a basis for clinical diagnosis in a timely manner. It is expected to provide a new and efficient technical support for the early and accurate diagnosis and personalized treatment of depression.

[0072] By using a TiO2@Au / g-C3N4 nanocomposite as a modifying material for the working electrode, along with a specific bioaptamer recognition element, the sensor's sensitivity can be significantly improved, achieving a low detection limit and enabling the detection of trace amounts of depression-related biomarkers. Furthermore, the components used in the disclosed body sensor manufacturing method exhibit excellent stability, resulting in a finished body sensor that maintains stable performance over extended periods, exhibits excellent reusability, and offers low detection costs, facilitating industrial applications.

[0073] To further illustrate the body sensor manufacturing method provided by the present disclosure, the following specific embodiments are provided:

[0074] Example 1:

[0075] Step S111: preparing TiO2@Au powder.

[0076] After boiling 99 mL of distilled water in a beaker, 3 mL of a 1% sodium citrate aqueous solution (reducing agent) was added while rapidly stirring and the mixture was boiled for another 10 minutes. Then, 2 g of 200 nm TiO2 powder was dispersed in the solution. After boiling for another 10 minutes, 1 mL of a 1% chloroauric acid aqueous solution was quickly added and the mixture was boiled for another 30 minutes. The solution was then transferred to a hydrothermal reactor and reacted at 150°C (the fourth temperature) for 2 hours (the fourth time). The mixture was then centrifuged and washed to produce the TiO2@Au composite material.

[0077] Step S112: preparing a g-C3N4 dispersion.

[0078] Prepare 50 ml of a 1.5 mol / L urea aqueous solution in a beaker, add 5 g of melamine, and continue stirring for 30 minutes. Then, place the resulting mixture in a hydrothermal reactor; after reacting at 150°C (i.e., the fifth temperature) for 8 hours (i.e., the fifth time), a g-C3N4 precursor is obtained. Then, the mixture is kept at 500°C (i.e., the sixth temperature) for 1.5 hours (i.e., the sixth time) in a muffle furnace. The obtained powder is ultrasonically dispersed in water for 30 minutes. After centrifugation, the supernatant obtained is the dispersion of ultrathin g-C3N4.

[0079] Step S110: preparing TiO2@Au slurry.

[0080] The prepared TiO2@Au composite material was uniformly mixed with various organic components in a specific ratio to form a TiO2@Au slurry. The specific ratios were: TiO2@Au powder: 67.55%; ethyl cellulose: 0.1%; acrylic resin (binder): 4%; dibasic ester (solvent): 22.5%; γ-(2,3-epoxypropoxy)propyltrimethoxysilane (accelerator): 4%; BYK 358N (surface additive): 1.5%; triolein (dispersant): 0.15%; and polysiloxane defoamer (defoaming agent): 0.5%.

[0081] Step S100: screen-printing the prepared TiO2@Au slurry on a conductive substrate, and keeping the temperature at 450°C (ie, the first temperature) for 60 minutes (ie, the first time) to obtain a TiO2@Au electrode.

[0082] Step S200: 200 μL of g-C3N4 dispersion is dropped onto the surface of the TiO2@Au electrode, and then kept at 300°C (i.e., the second temperature) in a muffle furnace for 1.5 h (i.e., the second time) to obtain a TiO2@Au / g-C3N4 photoanode.

[0083] Step S300: 20 μL of aptamer probe solution was added to the surface of the TiO2@Au / g-C3N4 photoanode and incubated at 37°C (the third temperature) for 1.5 h (the third time) to immobilize the bioaptamer on the surface of the working electrode.

[0084] Step S400: Rinse the electrode surface three times with ultrapure water to remove unbound bioaptamers, and then dry and store the sensor.

[0085] Example 2:

[0086] Step S111: preparing TiO2@Au powder.

[0087] 98 mL of distilled water was placed in a beaker and boiled. Then, 2 mL of 1.5% sodium citrate aqueous solution was added while rapidly stirring and the mixture was boiled for 5 minutes. 5 g of 50 nm TiO2 particles were dispersed in the solution and the mixture was boiled for 20 minutes. 2 mL of 1% chloroauric acid aqueous solution was quickly added and the mixture was boiled for 30 minutes. The solution was transferred to a hydrothermal reactor and reacted at 180°C (the fourth temperature) for 1 hour (the fourth time). The solution was then centrifuged and washed to obtain a TiO2@Au composite material.

[0088] Step S112: preparing a g-C3N4 dispersion.

[0089] Prepare 60 mL of 1.75 mol / L urea aqueous solution in a beaker, add 4.4 g of melamine, and continue stirring for 30 minutes. The resulting mixture is placed in a hydrothermal reactor and reacted at 160°C (i.e., the fifth temperature) for 12 hours (i.e., the fifth time) to obtain a g-C3N4 precursor. The mixture is then kept at 550°C (i.e., the sixth temperature) for 2 hours (i.e., the sixth time) in a muffle furnace. The obtained powder is ultrasonically dispersed in water for 30 minutes and centrifuged to obtain a supernatant, which is the dispersion of ultrathin g-C3N4.

[0090] Step S110: preparing TiO2@Au slurry.

[0091] The prepared TiO2@Au composite material was uniformly mixed with various organic components in a specific ratio to form a TiO2@Au slurry. The specific ratios were: TiO2@Au powder: 70.7%; ethyl cellulose: 0.75%; epoxy resin (binder): 5%; dibasic ester (solvent): 20%; γ-(2,3-epoxypropoxy)propyltrimethoxysilane (accelerator): 1.5%; BYK 381 (surface additive): 0.2%; BYK-111 (dispersant): 1.5%; and polysiloxane defoamer (defoaming agent): 0.35%.

[0092] Step S100: screen-printing the prepared TiO2@Au slurry on a conductive substrate, and keeping it at 400°C (ie, the first temperature) for 60 minutes (ie, the first time) to obtain a TiO2@Au electrode.

[0093] Step S200: 300 μL of g-C3N4 dispersion is added dropwise to the surface of the TiO2@Au electrode, and then kept at 350°C (i.e., the second temperature) in a muffle furnace for 0.5 h (i.e., the second time) to obtain a TiO2@Au / g-C3N4 photoanode.

[0094] Step S300: 40 μL of aptamer probe solution was added dropwise to the surface of the TiO2@Au / g-C3N4 photoanode and incubated at 37°C (i.e., the third temperature) for 1 h (i.e., the third time) to immobilize the bioaptamer on the surface of the working electrode.

[0095] Step S400: Rinse the electrode surface three times with PBS buffer solution to remove unbound bioaptamers, and then dry and store the sensor.

[0096] Example 3:

[0097] Step S111: preparing TiO2@Au powder.

[0098] 198 mL of distilled water was placed in a beaker and boiled. Then, 2 mL of a 2% sodium citrate aqueous solution and 1 mL of a 0.5% tannic acid aqueous solution (reducing agent) were added while rapidly stirring. The solution was boiled for 10 minutes, and 5 g of 200 nm TiO2 particles were dispersed in the solution. The solution was boiled for 15 minutes, and 10 mL of a 1% chloroauric acid aqueous solution was quickly added. The solution was boiled for 20 minutes. The solution was transferred to a hydrothermal reactor, reacted at 180°C (the fourth temperature) for 0.5 hours (the fourth time), and then centrifuged and washed to obtain a TiO2@Au composite material.

[0099] Step S112: preparing a g-C3N4 dispersion.

[0100] Prepare 50 ml of 1.6 mol / L urea aqueous solution in a beaker, add 4.1 g of melamine, and continue stirring for 30 minutes. Then, place the resulting mixture in a hydrothermal reactor and react at 140°C (i.e., the fifth temperature) for 3 hours (i.e., the fifth time) to obtain a g-C3N4 precursor. Then, keep it at 500°C (i.e., the sixth temperature) in a muffle furnace for 3 hours (i.e., the sixth time). The obtained powder is ultrasonically dispersed in water for 30 minutes. After centrifugation, the supernatant obtained is the dispersion of ultrathin g-C3N4.

[0101] Step S110: preparing TiO2@Au slurry.

[0102] The prepared TiO2@Au composite material was evenly mixed with various organic components in a specific ratio to form a TiO2@Au slurry. The specific ratios were: TiO2@Au powder: 75.05%; ethyl cellulose: 1.5%; epoxy resin (binder): 4.5%; dibasic ester (solvent): 15%; γ-aminopropyltriethoxysilane (accelerator): 1.5%; BYK 358N (surface additive): 0.25%; BYK111 (dispersant): 2%; and polysiloxane defoamer (defoaming agent): 0.2%.

[0103] Step S100: screen-printing the prepared TiO2@Au slurry on a conductive substrate, and keeping it at 250°C (ie, the first temperature) for 120 minutes (ie, the first time) to obtain a TiO2@Au electrode.

[0104] Step S200: 350 μL of g-C3N4 dispersion is added dropwise to the surface of the TiO2@Au electrode, and then kept at 200°C (i.e., the second temperature) for 2 h (i.e., the second time) in a muffle furnace to obtain a TiO2@Au / g-C3N4 photoanode.

[0105] Step S300: 10 μL of aptamer probe solution was added to the surface of the TiO2@Au / g-C3N4 photoanode and incubated at 37°C (the third temperature) for 2 h (the third time) to immobilize the bioaptamer on the surface of the working electrode.

[0106] Step S400: The electrode surface is rinsed five times with Tris-HCl buffer to remove unbound bioaptamers, and the sensor is then dried and stored.

[0107] refer to Figure 2 The morphology of the TiO2 powder used in Example 1 is shown in FIG. Figure 2 As shown in Figure 2, the size of titanium dioxide powder is about 100nm~200nm. Figure 3 The scanning electron microscope image of the TiO2@Au composite material prepared in Example 2 is shown. Figure 3 As shown in the figure, the size of TiO2@Au powder has not changed significantly, and the size of TiO2@Au powder is about 100nm~200nm. Figures 4 to 6 , Figure 4 Element mapping image of Ti element in the TiO2@Au composite material prepared in Example 2; Figure 5 Elemental mapping image of O element in the TiO2@Au composite material prepared in Example 2; Figure 6 This is the element mapping image of the Au element in the TiO2@Au composite material prepared in Example 2.

[0108] Figure 7The scanning electron microscope image of the surface of the TiO2@Au electrode after sintering in Example 2 is shown. Figure 7 As shown, the sintered titanium dioxide film has a uniformly dispersed porous structure.

[0109] To further demonstrate the effectiveness of the body sensor manufacturing method provided by the present disclosure, Comparative Examples 1 and 2 are provided, and the IT performance of the working electrodes in Example 3, Comparative Examples 1, and 2 is tested. Comparative Example 1 uses TiO2 as the working electrode, while Comparative Example 2 uses TiO2@Au as the working electrode. The details are as follows:

[0110] Comparative Example 1:

[0111] TiO2 powder and various organic components are mixed evenly in a certain proportion to form a TiO2 slurry. The specific proportions are: TiO2 powder: 75.05%; ethyl cellulose: 1.5%; epoxy resin: 4.5%; dibasic ester: 15%; γ-aminopropyltriethoxysilane: 1.5%; BYK 358N: 0.25%; BYK 111: 2%; polysiloxane defoamer: 0.2%.

[0112] The mixed slurry was screen-printed on a conductive substrate and kept at 350°C for 120 minutes to obtain a TiO2 electrode; 10 μL of aptamer probe solution was added to the surface of the TiO2 working electrode and incubated at 37°C for 2 hours to fix the bioaptamer on the working electrode surface; the electrode surface was rinsed four times with PBS buffer to remove unbound bioaptamer, and then the sensor was dried and stored.

[0113] Comparative Example 2:

[0114] Take 98mL of distilled water and place it in a beaker and boil it. Then, add 2mL of 1.5% sodium citrate aqueous solution while stirring rapidly and continue boiling for 5 minutes. Then, disperse 5g of 50nm TiO2 particles in the solution and continue boiling for 20 minutes. Then, quickly add 2mL of 1% chloroauric acid aqueous solution and continue boiling for 30 minutes. The above solution is transferred to a hydrothermal reactor, reacted at 180℃ for 1 hour, and then centrifuged and washed to obtain the TiO2@Au composite material.

[0115] The prepared TiO2@Au was evenly mixed with various organic components in a certain proportion to form a TiO2@Au slurry. The specific proportions were: TiO2@Au powder: 70.7%; ethyl cellulose: 0.75%; epoxy resin: 5%; dibasic ester: 20%; γ-(2,3-epoxypropoxy)propyltrimethoxysilane: 1.5%; BYK 381: 0.2%; BYK-111: 1.5%; polysiloxane defoamer: 0.35%.

[0116] The mixed slurry was screen-printed on a conductive substrate and kept at 400°C for 60 min to obtain a TiO2@Au electrode.

[0117] 10 μL of aptamer probe solution was added to the surface of the TiO2@Au working electrode and incubated at 37°C for 2 h to immobilize the bioaptamer on the working electrode surface. The electrode surface was rinsed four times with PBS buffer to remove unbound bioaptamer, and then the sensor was dried and stored.

[0118] The photoelectrochemical performance test was carried out in a three-electrode electrolytic cell, using 0.01 M phosphate buffer solution (PBS, pH = 7.4) as the electrolyte, a platinum sheet as the counter electrode, and Ag / AgCl as the reference electrode. Figure 8 The IT curve comparison diagram of the photoanode film of Example 3, Comparative Example 1 and Comparative Example 2 is shown, curve L1 is the IT performance of the working electrode (TiO2) in Comparative Example 1; curve L2 is the IT performance of the working electrode (TiO2@Au) in Comparative Example 2; curve L3 is the IT performance of the working electrode (TiO2@Au / g-C3N4) in Comparative Example 1. Figure 8 The horizontal axis is time, in seconds; the vertical axis is photocurrent, in microamperes.

[0119] from Figure 8 It can be seen that TiO2@Au / g-C3N4 as a working electrode has better photoelectric performance than TiO2@Au and TiO2.

[0120] TiO2@Au / g-C3N4 photoelectric sensors immobilized with serotonin aptamers and dopamine aptamers were used to detect serotonin solution and dopamine solution, respectively. 10 μL of serotonin solution and dopamine solution with different concentrations were dropped on the prepared electrodes and incubated at room temperature for 15 min. Then, the PEC signal was tested in 0.01 M phosphate buffer solution. The results are shown in Fig. Figure 9 、 Figure 10 Among them, the horizontal axis is the logarithm of the test concentration, and the vertical axis is the change in current.

[0121] The serotonin aptamer nucleic acid sequence is: 5′-HS-SH-CTC TCG GGA CGA CTG GTA GGC AGATAG GGG AAG CTG ATT CGA TGC GTG GGT CGT CCC-3′, and the dopamine aptamer nucleic acid sequence is: 5′-(SH)-(CH2)6-GGG AAU UCC GCG UGU GCG CCG CGG AAG AGG GAA UAU AGA GGC CAG CACAUA GUG AGG CCC UCC UCC C-3′.

[0122] refer to Figure 9 As shown in FIG. 1 , the detection results of serotonin by the body sensor provided in Example 2 are shown. It can be seen that the detection range of serotonin is 0.01 pg / mL to 1 ng / mL, and the detection limit is 0.003 pg / mL.

[0123] refer to Figure 10 As shown, the detection results of dopamine by the body sensor provided in Example 3 show that the detection range of dopamine is 0.01 pg / mL to 1 ng / mL, and the detection limit is 0.003 pg / mL.

[0124] from Figure 8 、 9 The experimental results of Figures 1 and 10 demonstrate that the present disclosure provides a photoelectrochemical biosensor suitable for ultrafast detection of depression. By manipulating the component ratios and preparation process of the TiO2@Au / g-C3N4 working electrode, a working electrode with excellent photoelectric performance can be obtained, significantly improving the sensitivity and stability of the photoelectrochemical biosensor. Furthermore, the body sensor fabricated by the present disclosure's body sensor manufacturing method offers a relatively low detection cost, a sensitive response, and a low detection limit, facilitating timely clinical diagnosis.

[0125] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include common knowledge or customary techniques in the art not disclosed herein. The description and examples are to be considered as exemplary only, with the true scope and spirit of the present disclosure being indicated by the appended claims.

Claims

1. A method for manufacturing a body sensor, characterized in that: include: Add reducing agent to the boiling water and continue to boil; Disperse titanium dioxide powder in the solution and continue boiling for 10-30 minutes; Add 1% chloroauric acid aqueous solution and continue boiling for 10-30 minutes to obtain the first reaction solution; Transferring the first reaction solution to a hydrothermal reactor and reacting at a fourth temperature for a fourth time to obtain TiO2@Au powder; 40-81.9% TiO2@Au powder, 0.1-2% ethyl cellulose, 3-8% binder, 15-35% solvent, 0-6% accelerator, 0-2% surface additive, 0-4% dispersant, and 0-1% defoamer were mixed to form a TiO2@Au slurry; Screen-printing the TiO2@Au slurry on a conductive substrate and maintaining the slurry at a first temperature for a first time to obtain a TiO2@Au electrode; Dropping or spin-coating a g-C3N4 dispersion on the surface of the TiO2@Au electrode, and maintaining the temperature at a second temperature for a second time to obtain a TiO2@Au / g-C3N4 photoanode; Adding an aptamer probe solution dropwise onto the surface of the TiO2@Au / g-C3N4 photoanode and incubating at a third temperature for a third time, wherein the aptamer probe comprises a DNA aptamer probe for serotonin and / or a DNA aptamer probe for dopamine; The TiO2@Au / g-C3N4 photoanode surface was rinsed to obtain a bulk sensor.

2. The method for manufacturing a body sensor according to claim 1, wherein: The titanium dioxide powder includes one or more of nano titanium dioxide powder, submicron titanium dioxide powder and micron titanium dioxide powder.

3. The method for manufacturing a body sensor according to claim 1, wherein: The 1% chloroauric acid aqueous solution is added, wherein the mass of the added chloroauric acid is 0.1% to 5% of the titanium dioxide powder.

4. The method for manufacturing a body sensor according to claim 1, wherein: A reducing agent is added to the boiling water and the boiling is continued, wherein the reducing agent includes one or more of sodium citrate and tannic acid, and the concentration of the reducing agent is 0.5% to 2.5%.

5. The method for manufacturing a body sensor according to claim 1, wherein: The body sensor manufacturing method further includes preparing a g-C3N4 dispersion; the preparation of the g-C3N4 dispersion includes: Prepare a 1.5 mol / L urea aqueous solution, add melamine, and continue stirring for 30 minutes to obtain a second reaction solution; Transferring the second reaction solution to a hydrothermal reactor and reacting at a fifth temperature for a fifth time to obtain a g-C3N4 precursor; Keeping the g-C3N4 precursor in a muffle furnace at a sixth temperature for a sixth time to obtain g-C3N4 powder; The g-C3N4 powder is ultrasonically dispersed in water for 10 to 60 minutes, and the supernatant obtained after centrifugation is the g-C3N4 dispersion.

6. The method for manufacturing a body sensor according to claim 5, wherein: When a 1.5 mol / L urea aqueous solution is prepared and melamine is added, the molar mass ratio of melamine to urea is 1:2~1:

5.

7. The method for manufacturing a body sensor according to claim 5, wherein: The first temperature is 250°C~500°C, and the first time is 20~120 minutes; the second temperature is 100°C~500°C, and the second time is 0.5~3 hours; the third temperature is 37°C, and the third time is 10~120 minutes; the fourth temperature is 120~180°C, and the fourth time is 0.5~24 hours; the fifth temperature is 110~180°C, and the fifth time is 2~24 hours; the sixth temperature is 400~650°C, and the sixth time is 0.5~5 hours.

8. The method for manufacturing a body sensor according to claim 1, wherein: The surface of the TiO2@Au / g-C3N4 photoanode is rinsed with one or more liquids selected from ultrapure water, sterile water, PBS buffer, and Tris-HCl buffer.

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