Body sensor manufacturing method

Abstract

The invention discloses a body sensor manufacturing method, and relates to the technical field of photoelectrochemical biotechnology detection. The body sensor manufacturing method comprises the steps that TiO2 (at) Au slurry is printed on a conductive substrate in a silk-screen mode, heat preservation is conducted for a first time at a first temperature, a TiO2 (at) Au electrode is obtained, and the concentration of TiO2 (at) Au powder in the TiO2 (at) Au slurry is 40%-81.9%; dropwise adding or spin-coating a g-C3N4 dispersion liquid on the surface of the TiO2 (at) Au electrode, and keeping the temperature for a second time at a second temperature to obtain a TiO2 (at) Au / g-C3N4 photo-anode; an aptamer probe solution is dropwise added to the surface of the TiO2 (at) Au / g-C3N4 photo-anode, incubation is conducted at the third temperature for the third time, and aptamer probes comprise a DNA aptamer probe of serotonin and / or a DNA aptamer probe of dopamine; and washing the surface of the TiO2 (at) Au / g-C3N4 photo-anode to obtain the body sensor. The body sensor manufacturing method provided by the invention can be used for preparing the photoelectrochemical biological aptamer sensor based on the TiO2 (at) Au / g-C3N4 nano composite material so as to quickly and sensitively detect depression related biomarkers, and is beneficial to meeting the requirements of early detection and large-scale inspection.

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 seriously affects the physical and mental health of people around the world. Its rising incidence has brought tremendous pressure and challenges to society and families. In view of this, rapid detection and early diagnosis of depression are extremely important.

[0003] At present, traditional methods for detecting depression have significant limitations. Clinical symptom assessment relies on professional doctors, which is highly subjective, early symptoms are easily overlooked, and there is a lack of objective quantitative indicators. Biomarker (serotonin, dopamine) detection such as fluorescence measurement, thin layer chromatography, gas chromatography, gas chromatography-mass spectrometry, high performance liquid chromatography, etc., are complex to operate, require professionals and equipment, have long detection time, high cost, and poor sensitivity. All these make it difficult to meet the needs of early detection and large-scale inspections. Summary of the invention

[0004] The present invention provides a method for manufacturing a body sensor, which can prepare a body sensor based on TiO 2 @Au / gC 3 N 4 Nanocomposite photoelectrochemical bioaptamer sensors can be used for rapid and sensitive detection of depression-related biomarkers, which is conducive to meeting the needs of early detection and large-scale examination.

[0005] The present disclosure provides a method for manufacturing a body sensor, comprising: TiO 2 @Au slurry is screen-printed on a conductive substrate and kept at a first temperature for a first time to obtain TiO 2 @Au electrode, TiO 2 @TiO in Au slurry 2 @The concentration of Au powder is 40%~81.9%; In TiO 2 @G-C is added by dropping or spin coating on the Au electrode surface 3 N 4 The dispersion is kept at a second temperature for a second time to obtain TiO 2 @Au / gC 3 N 4 Photoanode; In TiO 2 @Au / gC 3 N 4Adding an aptamer probe solution dropwise onto the surface of the 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; Rinse TiO 2 @Au / gC 3 N 4 Photoanode surface, to obtain a bulk sensor.

[0006] In an exemplary embodiment of the present disclosure, the body sensor manufacturing method further includes preparing TiO 2 @Au slurry; Preparation of TiO 2 @Au slurry, including: 40~81.9%TiO 2 @Au powder, 0.1~2% ethyl cellulose, 3~8% binder, 15~35% solvent, 0~6% accelerator, 0~2% surface additive, 0~4% dispersant, 0~1% defoamer are mixed evenly to form TiO 2 @Au slurry.

[0007] In an exemplary embodiment of the present disclosure, TiO 2 @Au slurry, also includes the preparation of TiO 2 @Au powder; preparation of TiO 2 @Au powder, including: Add reducing agent to boiling water and continue boiling; 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; The first reaction solution is transferred to a hydrothermal reactor and reacted at a fourth temperature for a fourth time to obtain TiO 2 @Au powder.

[0008] 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.

[0009] 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.

[0010] 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%.

[0011] In an exemplary embodiment of the present disclosure, the body sensor manufacturing method further includes preparing gC 3 N 4 Dispersion; Preparation of gC 3 N 4 Dispersions comprising: A 1.5 mol / L urea aqueous solution was prepared, and melamine was added, and the mixture was stirred for 30 minutes to obtain a second reaction solution; The second reaction solution was transferred to a hydrothermal reactor and reacted at a fifth temperature for a fifth time to obtain gC 3 N 4 Precursor; G C 3 N 4 The precursor is kept in the muffle furnace at the sixth temperature for the sixth time to obtain gC 3 N 4 Powder; G C 3 N 4 The powder is ultrasonically dispersed in water for 10-60 minutes, and the supernatant obtained after centrifugation is gC 3 N 4 Dispersion.

[0012] 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.

[0013] In an exemplary embodiment of the present disclosure, the first temperature is 250°C~500°C, and the first time is 20~120 min; the second temperature is 100°C~500°C, and the second time is 0.5~3 h; the third temperature is 37°C, and the third time is 10~120 min; the fourth temperature is 120~180°C, and the fourth time is 0.5~24 h; the fifth temperature is 110~180°C, and the fifth time is 2~24 h; the sixth temperature is 400~650°C, and the sixth time is 0.5~5 h.

[0014] In an exemplary embodiment of the present disclosure, washing the TiO 2 @Au / gC 3 N 4 On the surface of the photoanode, the liquid used includes one or more of ultrapure water, sterile water, PBS buffer, and Tris-HCl buffer.

[0015] The body sensor manufacturing method provided in the present disclosure comprises preparing TiO 2 @Au / gC 3 N 4The photoanode, i.e., the working electrode of the body sensor, then incubates specific bioaptamer probes of serotonin and dopamine on the surface of the working electrode through step S300. The sensor assembles a nanocomposite material made of titanium dioxide coated with gold nanoparticles and an ultra-thin layer of graphite phase carbon nitride two-dimensional material, and combines it with specific bioaptamers to achieve rapid and sensitive detection of depression-related biomarkers.

[0016] 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 present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings herein are incorporated into the specification 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 accompanying drawings described below are only some embodiments of the present disclosure, and for ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without creative work.

[0018] Figure 1 The present invention is a flow chart of an exemplary embodiment of a method for manufacturing a body sensor according to the present invention.

[0019] Figure 2 The TiO2 used in the embodiment 1 of the method for manufacturing the body sensor disclosed in the present invention is 2 Powder morphology.

[0020] Figure 3 The TiO prepared in Example 2 of the body sensor manufacturing method disclosed in the present invention 2 @Scanning electron microscope image of Au composite material.

[0021] Figure 4 The TiO prepared in Example 2 of the body sensor manufacturing method disclosed in the present invention 2 @Elemental mapping image of Ti element in Au composite material.

[0022] Figure 5 The TiO prepared in Example 2 of the body sensor manufacturing method disclosed in the present invention 2 @Elemental mapping image of O element in Au composite material.

[0023] Figure 6 The TiO prepared in Example 2 of the body sensor manufacturing method disclosed in the present invention 2 @AuElemental mapping image of Au element in composite materials.

[0024] Figure 7 The TiO2 after sintering in the embodiment 2 of the body sensor manufacturing method disclosed in the present invention is 2 @Scanning electron microscope image of the Au electrode surface.

[0025] Figure 8 It 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 in the present invention.

[0026] Fig. 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.

[0027] Fig.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

[0028] Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in a variety of forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that the present disclosure will be comprehensive and complete and fully convey the concepts of the example embodiments to those skilled in the art. The same reference numerals in the figures represent the same or similar structures, and thus their detailed description will be omitted. In addition, the drawings are only schematic illustrations of the present disclosure and are not necessarily drawn to scale.

[0029] Unless otherwise specified or explained, the technical terms or scientific terms used in the present disclosure shall have the common meanings understood by people with ordinary skills in the field to which the present disclosure belongs. The terms "one", "an", "the", "said" 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 indicate an open-ended inclusion and mean that there may be other elements / components / etc. in addition to the listed elements / components / etc.; the terms "first" and "second" are used only as labels and are not used to limit the quantity, importance or order of their objects.

[0030] When describing the proportion of each component in the present disclosure, unless otherwise specified, it refers to the mass fraction of the component.

[0031] Traditional methods for detecting depression have significant limitations. Clinical symptom assessment relies on professional doctors, is highly subjective, early symptoms are easily overlooked, and lack objective quantitative indicators. Biomarker (serotonin, dopamine) detection, such as fluorescence measurement, thin layer chromatography, gas chromatography, gas chromatography-mass spectrometry, high performance liquid chromatography, etc., is complex to operate, requires professionals and equipment, has a long detection time, high cost, and poor sensitivity. All of these make it difficult to meet the needs of early detection and large-scale inspections.

[0032] In view of the above problems, the present invention provides a method for manufacturing a body sensor for preparing a TiO-based 2 @Au / gC3 N 4 Nanocomposite photoelectrochemical bioaptamer sensors. Figure 1 As shown, including: Step S100: TiO 2 @Au slurry is screen-printed on a conductive substrate and kept at a first temperature for a first time to obtain TiO 2 @Au electrode, TiO 2 @TiO in Au slurry 2 @The concentration of Au powder is 40%~81.9%; Step S200: 2 @G-C is added by dropping or spin coating on the Au electrode surface 3 N 4 The dispersion is kept at a second temperature for a second time to obtain TiO 2 @Au / gC 3 N 4 Photoanode; Step S300: 2 @Au / gC 3 N 4 Adding an aptamer probe solution dropwise onto the surface of the 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; Step S400: Rinse TiO 2 @Au / gC 3 N 4 Photoanode surface, to obtain a bulk sensor.

[0033] The body sensor manufacturing method provided in the present disclosure comprises preparing TiO 2 @Au / gC 3 N 4 The photoanode, i.e., the working electrode of the body sensor, then incubates specific bioaptamer probes of serotonin and dopamine on the surface of the working electrode through step S300. The sensor assembles a nanocomposite material made of titanium dioxide coated with gold nanoparticles and an ultra-thin layer of graphite phase carbon nitride two-dimensional material, and combines it with specific bioaptamers to achieve rapid and sensitive detection of depression-related biomarkers.

[0034] In an exemplary embodiment of the present disclosure, the body sensor manufacturing method further includes step S110: preparing TiO 2 @Au slurry; specifically including: 40~81.9%TiO 2@Au powder, 0.1~2% ethyl cellulose, 3~8% binder, 15~35% solvent, 0~6% accelerator, 0~2% surface additive, 0~4% dispersant, 0~1% defoamer are mixed evenly to form TiO 2 @Au slurry.

[0035] Among them, the preparation of TiO 2 @Au slurry may also include step S111: preparing TiO 2 @Au powder. Specifically including: Add reducing agent to boiling water and continue boiling; 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; The first reaction solution is transferred to a hydrothermal reactor and reacted at a fourth temperature for a fourth time to obtain TiO 2 @Au powder.

[0036] For example, a reducing agent is added to the boiling water, wherein the reducing agent may include one or more of sodium citrate and tannic acid, and 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, and then an appropriate amount of the above reducing agent is added while rapidly stirring and the boiling is continued for 5 to 10 minutes, and then a certain amount of TiO 2 The particles are dispersed in the solution and the boiling is continued. The titanium dioxide powder may include one or more of nano titanium dioxide powder, submicron titanium dioxide powder and micron titanium dioxide powder. After continuing to boil for 10 to 30 minutes, a 1% chloroauric acid aqueous solution is quickly added, and the boiling is continued for 10 to 30 minutes to obtain a first reaction solution. Exemplarily, when a 1% chloroauric acid aqueous solution is added, the mass of the chloroauric acid added is 0.1% to 5% of the titanium dioxide powder.

[0037] The first reaction solution is transferred to a hydrothermal reactor and reacted at a fourth temperature for a fourth time to obtain TiO 2 @Au powder. Exemplarily, the hydrothermal reaction temperature (ie, the fourth temperature) of the first reaction solution in the hydrothermal reactor is 120-180° C., and the reaction time (ie, the fourth time) is 0.5-24 h.

[0038] In an exemplary embodiment of the present disclosure, the body sensor manufacturing method further includes step S112: preparing gC 3 N 4 Dispersion liquid, specifically comprising: A 1.5 mol / L urea aqueous solution was prepared, and melamine was added, and the mixture was stirred for 30 minutes to obtain a second reaction solution; The second reaction solution was transferred to a hydrothermal reactor and reacted at a fifth temperature for a fifth time to obtain gC 3 N 4 Precursor; G C 3 N 4 The precursor is kept in the muffle furnace at the sixth temperature for the sixth time to obtain gC 3 N 4 Powder; G C 3 N 4 The powder is ultrasonically dispersed in water for 10-60 minutes, and the supernatant obtained after centrifugation is gC 3 N 4 Dispersion.

[0039] 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, and the second reaction solution is placed in a hydrothermal reactor, and reacted at a fifth temperature for a fifth time to obtain gC 3 N 4 Specifically, the hydrothermal reaction temperature (ie, the fifth temperature) of the second reaction solution in the hydrothermal reactor is 110-180° C., and the reaction time (ie, the fifth time) is 2-24 hours.

[0040] Get gC 3 N 4 After the precursor, gC 3 N 4 The precursor is kept in a muffle furnace at a sixth temperature for a sixth time, and the obtained powder is then ultrasonically dispersed in water for 10 to 60 minutes. The supernatant obtained after centrifugation is the ultrathin gC 3 N 4 Specifically, gC 3 N 4 The heat treatment temperature (i.e., the sixth temperature) of the precursor in the muffle furnace is 400-650° C., and the holding time (i.e., the sixth time) is 0.5-5 h.

[0041] Preparation of TiO 2 @Au slurry, in step S100, TiO 2 @Au slurry is screen-printed on a conductive substrate and kept at a first temperature for a first time to obtain TiO 2 @Au electrode. Specifically, after screen printing, the temperature is kept at 250~500℃ for 20~120min to obtain TiO 2 @Au electrode.

[0042] In step S200, in TiO2 @A certain amount of gC is added or spin-coated on the Au electrode surface 3 N 4 The dispersion can be prepared by dropping or spin coating the gC 3 N 4 Then, the dispersion is kept in a muffle furnace at a second temperature for a second time to obtain TiO 2 @Au / gC 3 N 4 Specifically, gC is added dropwise or spin-coated 3 N 4 Dispersion TiO 2 @The heat treatment temperature (i.e., the second temperature) of the Au electrode in the muffle furnace can be 100~500°C, and the holding time (i.e., the second time) can be 0.5~3h.

[0043] In step S300, in TiO 2 @Au / gC 3 N 4 The aptamer probe solution is dripped onto the surface of the photoanode. The aptamer probe may include a DNA aptamer probe for serotonin and / or a DNA aptamer probe for dopamine, thereby achieving a high sensitivity and rapid response to depression-related biomarkers. 2 @Au / gC 3 N 4 The photoanode was incubated at 37°C for 10-120 min to immobilize the bioaptamer on the surface of the working electrode.

[0044] In step S400, the TiO 2 @Au / gC 3 N 4 The unbound bioaptamer in step S300 is removed from the photoanode surface, and the obtained biosensor can then be stored at a certain temperature for later use. For example, the TiO 2 @Au / gC 3 N 4 The photoanode surface was rinsed to ensure complete removal of unbound aptamers.

[0045] The TiO-based 2 @Au / gC 3 N 4Nanocomposite photoelectrochemical bioaptamer sensors can be used to quickly detect depression. Experiments have shown that the detection time can be shortened to less than 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.

[0046] By using TiO 2 @Au / gC 3 N 4 Nanocomposites as modified materials for working electrodes and specific bioaptamer recognition elements can significantly improve the sensitivity of sensors, and the detection limit can reach a low level, which can detect trace amounts of depression-related biomarkers. Moreover, the components used in the body sensor manufacturing method provided by the present disclosure have good stability, and the prepared body sensor product can maintain stable performance for a long time, has good reusability, and has a low detection cost, which is conducive to industrial application.

[0047] In order to further illustrate the body sensor manufacturing method provided by the present disclosure, the following specific embodiments are provided: Embodiment 1: Step S111: Preparation of TiO 2 @Au powder.

[0048] Take 99 mL of distilled water and boil it in a beaker. Then add 3 mL of 1% sodium citrate aqueous solution (reducing agent) while stirring rapidly. Continue boiling for 10 minutes. Then add 2 g of 200 nm TiO 2 The powder was dispersed in the solution. After boiling for 10 minutes, 1 mL of 1% chloroauric acid aqueous solution was quickly added and the solution was boiled for 30 minutes. The solution was transferred to a hydrothermal reactor and reacted at 150°C (the fourth temperature) for 2 hours (the fourth time). After centrifugation and washing, TiO 2 @Au composite material.

[0049] Step S112: Preparation of gC 3 N 4 Dispersion.

[0050] Prepare 50 ml of 1.5 mol / L urea aqueous solution in a beaker, add 5 g of melamine, and continue stirring for 30 min. Then, place the resulting mixture in a hydrothermal reactor. After reacting at 150 °C (i.e., the fifth temperature) for 8 h (i.e., the fifth time), gC 3 N 4 The precursor is then kept at 500°C (i.e., the sixth temperature) in a muffle furnace for 1.5 h (i.e., the sixth time), the obtained powder is ultrasonically dispersed in water for 30 min, and the supernatant obtained after centrifugation is the ultrathin gC 3 N4 of dispersion.

[0051] Step S110: Preparation of TiO 2 @Au slurry.

[0052] The prepared TiO 2 @Au composite materials are mixed with various organic components in a certain proportion to form TiO 2 @Au slurry. The specific ratio is: TiO 2 @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%; polysiloxane defoamer (defoaming agent): 0.5%.

[0053] Step S100: Prepare the TiO 2 @Au paste was screen-printed on a conductive substrate and kept at 450°C (i.e., the first temperature) for 60 min (i.e., the first time) to obtain TiO 2 @Au electrode.

[0054] Step S200: 2 Add 200 μL of gC to the surface of Au electrode 3 N 4 The dispersion was 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 TiO 2 @Au / gC 3 N 4 Photoanode.

[0055] Step S300: 2 @Au / gC 3 N 4 20 μL of aptamer probe solution was dropped onto the surface of the photoanode and incubated at 37° C. (i.e., the third temperature) for 1.5 h (i.e., the third time) to immobilize the bioaptamer on the surface of the working electrode.

[0056] Step S400: Rinse the electrode surface with ultrapure water for 3 times to remove unbound bioaptamers, and then dry and store the sensor.

[0057] Embodiment 2: Step S111: Preparation of TiO 2 @Au powder.

[0058] Take 98 mL of distilled water and boil it in a beaker. Then add 2 mL of 1.5% sodium citrate aqueous solution while stirring rapidly. Continue boiling for 5 min. Then add 5 g of 50 nm TiO 2 The particles were dispersed in the solution, and after boiling for 20 min, 2 mL of 1% chloroauric acid aqueous solution was quickly added and the solution was boiled for 30 min. The solution was transferred to a hydrothermal reactor, and reacted at 180 °C (i.e., the fourth temperature) for 1 h (i.e., the fourth time), and then centrifuged and washed to obtain TiO 2 @Au composite material.

[0059] Step S112: Preparation of gC 3 N 4 Dispersion.

[0060] 60 mL of 1.75 mol / L urea aqueous solution was prepared in a beaker, and 4.4 g of melamine was added. After continuous stirring for 30 min, the resulting mixture was placed in a hydrothermal reactor and reacted at 160 ° C (i.e., the fifth temperature) for 12 h (i.e., the fifth time) to obtain gC 3 N 4 The precursor is then kept at 550°C (i.e., the sixth temperature) in a muffle furnace for 2 h (i.e., the sixth time), the obtained powder is ultrasonically dispersed in water for 30 min, and the supernatant obtained after centrifugation is the ultrathin gC 3 N 4 of dispersion.

[0061] Step S110: Preparation of TiO 2 @Au slurry.

[0062] The prepared TiO 2 @Au composite materials are mixed with various organic components in a certain proportion to form TiO 2 @Au slurry. The specific ratio is: TiO 2 @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%; polysiloxane defoamer (defoamer): 0.35%.

[0063] Step S100: Prepare the TiO 2 @Au paste was screen-printed on a conductive substrate and kept at 400°C (i.e., the first temperature) for 60 min (i.e., the first time) to obtain TiO 2 @Au electrode.

[0064] Step S200: 2Add 300 μL of gC to the surface of Au electrode 3 N 4 The dispersion was 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 TiO 2 @Au / gC 3 N 4 Photoanode.

[0065] Step S300: 2 @Au / gC 3 N 4 40 μL of aptamer probe solution was dropped onto the surface of the 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.

[0066] Step S400: The electrode surface is rinsed three times with PBS buffer solution to remove unbound bioaptamers, and then the sensor is dried and stored.

[0067] Embodiment three: Step S111: Preparation of TiO 2 @Au powder.

[0068] Take 198 mL of distilled water and boil it in a beaker. Then add 2 mL of 2% sodium citrate aqueous solution and 1 mL of 0.5% tannic acid aqueous solution (reducing agent) while stirring rapidly. Continue boiling for 10 minutes and then add 5 g of 200 nm TiO 2 The particles were dispersed in the solution, and after boiling for 15 min, 10 mL of 1% chloroauric acid aqueous solution was quickly added and the solution was boiled for 20 min. The solution was transferred to a hydrothermal reactor, and reacted at 180 °C (i.e., the fourth temperature) for 0.5 h (i.e., the fourth time), and then centrifuged and washed to obtain TiO 2 @Au composite material.

[0069] Step S112: Preparation of gC 3 N 4 Dispersion.

[0070] 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 min. Then, place the resulting mixture in a hydrothermal reactor and react at 140 °C (i.e., the fifth temperature) for 3 h (i.e., the fifth time) to obtain gC 3 N 4 The precursor is then kept at 500°C (i.e., the sixth temperature) in a muffle furnace for 3 h (i.e., the sixth time), the obtained powder is ultrasonically dispersed in water for 30 min, and the supernatant obtained after centrifugation is the ultrathin gC 3 N 4 of dispersion.

[0071] Step S110: Preparation of TiO 2 @Au slurry.

[0072] The prepared TiO 2 @Au composite materials are mixed with various organic components in a certain proportion to form TiO 2 @Au slurry. The specific ratio is: TiO 2 @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%; polysiloxane defoamer (defoaming agent): 0.2%.

[0073] Step S100: Prepare the TiO 2 @Au paste was screen-printed on a conductive substrate and kept at 250°C (i.e., the first temperature) for 120 min (i.e., the first time) to obtain TiO 2 @Au electrode.

[0074] Step S200: 2 Add 350 μL of gC to the surface of the Au electrode 3 N 4 The dispersion was then kept at 200°C (i.e., the second temperature) for 2 h (i.e., the second time) in a muffle furnace to obtain TiO 2 @Au / gC 3 N 4 Photoanode.

[0075] Step S300: 2 @Au / gC 3 N 4 10 μL of aptamer probe solution was dropped onto the surface of the photoanode and incubated at 37° C. (i.e., the third temperature) for 2 h (i.e., the third time) to immobilize the bioaptamer on the surface of the working electrode.

[0076] Step S400: The electrode surface is rinsed 5 times with Tris-HCl buffer to remove unbound bioaptamers, and then the sensor is dried and stored.

[0077] refer to Figure 2 The TiO 2 The morphology of the powder, such as Figure 2 As shown, the size of titanium dioxide powder is about 100nm~200nm. Figure 3 The TiO prepared in Example 2 is shown 2 @SEM images of Au composite materials, such as Figure 3 As shown, TiO 2 @Au powder size has no obvious change, TiO 2 @The size of Au powder is about 100nm~200nm. Using scanning electron microscope energy spectrum analysis technology, we get Figures 4 to 6 , Figure 4 The TiO prepared in Example 2 2 @Elemental mapping image of Ti element in Au composite material; Figure 5 The TiO prepared in Example 2 2 @Elemental mapping image of O element in Au composite material; Figure 6 The TiO prepared in Example 2 2 @AuElemental mapping image of Au element in composite materials.

[0078] Figure 7 The sintered TiO 2 @Scanning electron microscope image of the Au electrode surface, such as Figure 7 As shown, the sintered titanium dioxide film is a uniformly dispersed porous structure.

[0079] In order to further demonstrate the effect 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 embodiment 3, comparative example 1 and comparative example 2 is tested. 2 As the working electrode, Comparative Example 2 uses TiO 2 @Au is used as the working electrode. The details are as follows: Comparative Example 1: TiO 2 The powder is mixed with various organic components in a certain proportion to form TiO 2 Slurry. The specific ratio is: TiO 2 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%.

[0080] The mixed slurry was screen-printed on a conductive substrate and kept at 350 °C for 120 min to obtain TiO 2 Electrode; in TiO 2 10 μL of aptamer probe solution was added to the surface of the working electrode and incubated at 37°C for 2 h to fix the bioaptamer on the surface of the working electrode; the electrode surface was rinsed 4 times with PBS buffer to remove unbound bioaptamer, and then the sensor was dried and stored.

[0081] Comparative Example 2: Take 98 mL of distilled water and boil it in a beaker. Then add 2 mL of 1.5% sodium citrate aqueous solution while stirring rapidly. Continue boiling for 5 min. Then add 5 g of 50 nm TiO 2 The particles were dispersed in the solution, and after boiling for 20 min, 2 mL of 1% chloroauric acid aqueous solution was quickly added and boiled for 30 min. The solution was transferred to a hydrothermal reactor, reacted at 180 °C for 1 h, and then centrifuged and washed to obtain TiO 2 @Au composite material.

[0082] The prepared TiO 2 @Au is mixed with various organic components in a certain proportion to form TiO 2 @Au slurry, the specific ratio is: TiO 2 @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%.

[0083] The mixed slurry was screen-printed on a conductive substrate and kept at 400 °C for 60 min to obtain TiO 2 @Au electrode; In TiO 2 10 μL of aptamer probe solution was added to the surface of the @Au working electrode and incubated at 37°C for 2 h to fix the bioaptamer on the surface of the working electrode; the electrode surface was rinsed 4 times with PBS buffer to remove the unbound bioaptamer, and then the sensor was dried and stored.

[0084] 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, 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, and curve L1 is the working electrode (TiO 2 ) of the IT performance; Curve L2 is the working electrode (TiO 2 @Au) of the working electrode; Curve L3 is the IT performance of the working electrode (TiO 2 @Au / gC 3 N 4 )’s IT performance. Figure 8 The horizontal axis is time, in seconds; the vertical axis is photocurrent, in microamperes.

[0085] from Figure 8 It can be seen that TiO 2@Au / gC 3 N 4 As working electrode, TiO 2 @Au and TiO 2 It has better photoelectric performance.

[0086] TiO2 immobilized with serotonin aptamer and dopamine aptamer 2 @Au / gC 3 N 4 The photoelectric sensor was used to detect serotonin solution and dopamine solution. 10 μL of serotonin solution and dopamine solution of different concentrations were dropped on the prepared electrode 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. 9 , Fig.10 Among them, the horizontal axis is the logarithm of the test concentration, and the vertical axis is the change in current.

[0087] Among them, 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′.

[0088] refer to Fig. 9 As shown, the detection result of serotonin by the body sensor provided in Example 2, it can be seen that the detection range of serotonin is: 0.01pg / mL~1ng / mL, and the detection limit is 0.003pg / mL.

[0089] refer to Fig.10 As shown, the detection result of dopamine by the body sensor provided in Example 3, it can be seen that the detection range of dopamine is: 0.01pg / mL~1ng / mL, and the detection limit is 0.003pg / mL.

[0090] from Figure 8 , 9 , 10, it can be seen that the present disclosure provides a photoelectrochemical biosensor suitable for ultrafast detection of depression. 2 @Au / gC 3 N 4The component ratio and preparation process of the working electrode can obtain a working electrode with excellent photoelectric performance, thereby greatly improving the sensitivity and stability of the photoelectrochemical biosensor. In addition, the body sensor prepared by the body sensor manufacturing method provided by the present disclosure has a relatively low detection cost, a sensitive response, and a low detection limit, which is conducive to providing a basis for clinical diagnosis in a timely manner.

[0091] 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 modification, use or adaptation of the present disclosure, which follows the general principles of the present disclosure and includes common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present disclosure are indicated by the appended claims.

Claims

1. A method for manufacturing a body sensor, characterized in that: include: Screen-printing TiO2@Au slurry on 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%; Dropping or spin coating a g-C3N4 dispersion on the surface of the TiO2@Au electrode, and keeping 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 is rinsed to obtain a bulk sensor.

2. The method for manufacturing a body sensor according to claim 1, wherein: The body sensor manufacturing method further includes preparing TiO2@Au slurry; The TiO2@Au slurry is prepared, comprising: 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 uniformly mixed to form the TiO2@Au slurry.

3. The method for manufacturing a body sensor according to claim 2, wherein: The preparation of the TiO2@Au slurry also includes preparing TiO2@Au powder; The preparation of the TiO2@Au powder comprises: Add reducing agent to boiling water and continue boiling; 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; The first reaction solution is transferred to a hydrothermal reactor for reaction at a fourth temperature for a fourth time to obtain the TiO2@Au powder.

4. The method for manufacturing a body sensor according to claim 3, wherein: The titanium dioxide powder includes one or more of nano titanium dioxide powder, submicron titanium dioxide powder and micron titanium dioxide powder.

5. The method for manufacturing a body sensor according to claim 3, 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.

6. The method for manufacturing a body sensor according to claim 3, wherein: Add a reducing agent to the boiling water and continue boiling, 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%.

7. The method for manufacturing a body sensor according to claim 3, wherein: The body sensor manufacturing method further includes preparing a g-C3N4 dispersion; preparing the g-C3N4 dispersion includes: A 1.5 mol / L urea aqueous solution was prepared, and melamine was added, and the mixture was stirred 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; The g-C3N4 precursor is kept in a muffle furnace at a sixth temperature for a sixth time to obtain a 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.

8. The method for manufacturing a body sensor according to claim 7, 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.

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

10. The method for manufacturing a body sensor according to claim 1, wherein: 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.

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